199 results on '"Crowther, NJ"'
Search Results
2. A randomized clinical trial comparing metabolic parameters after 48 weeks of standard- and low-dose stavudine therapy and tenofovir disoproxil fumarate therapy in HIV-infected South African patients
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Menezes, CN, Crowther, NJ, Duarte, R, Van Amsterdam, D, Evans, D, Dickens, C, Dix-Peek, T, Rassool, M, Prinsloo, A, Raal, F, and Sanne, I
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- 2014
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3. Genomic and environmental risk factors for cardiametabolic diseases in Africa: methods used for Phase 1 of the AWI-Gen population cross-sectional study
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Ali, SA, Soo, C, Agongo, G, Alberts, M, Amenga-Etego, L, Boua, RP, Choudhury, A, Crowther, NJ, Depuur, C, Gomez-Olive, FX, Guiraud, I, Haregu, TN, Hazelhurst, S, Kahn, K, Khayeka-Wandabwa, C, Kyobutungi, C, Lombard, Z, Mashinya, F, Micklesfield, L, Mohamed, SF, Mukomana, F, Nakanabo-Diallo, S, Natama, HM, Ngomi, N, Nonterah, EA, Norris, SA, Oduro, AR, Some, AM, Sorgho, H, Tindana, P, Tinto, H, Tollman, S, Twine, R, Wade, A, Sankoh, O, Ramsay, M, Ali, SA, Soo, C, Agongo, G, Alberts, M, Amenga-Etego, L, Boua, RP, Choudhury, A, Crowther, NJ, Depuur, C, Gomez-Olive, FX, Guiraud, I, Haregu, TN, Hazelhurst, S, Kahn, K, Khayeka-Wandabwa, C, Kyobutungi, C, Lombard, Z, Mashinya, F, Micklesfield, L, Mohamed, SF, Mukomana, F, Nakanabo-Diallo, S, Natama, HM, Ngomi, N, Nonterah, EA, Norris, SA, Oduro, AR, Some, AM, Sorgho, H, Tindana, P, Tinto, H, Tollman, S, Twine, R, Wade, A, Sankoh, O, and Ramsay, M
- Abstract
There is an alarming tide of cardiovascular and metabolic disease (CMD) sweeping across Africa. This may be a result of an increasingly urbanized lifestyle characterized by the growing consumption of processed and calorie-dense food, combined with physical inactivity and more sedentary behaviour. While the link between lifestyle and public health has been extensively studied in Caucasian and African American populations, few studies have been conducted in Africa. This paper describes the detailed methods for Phase 1 of the AWI-Gen study that were used to capture phenotype data and assess the associated risk factors and end points for CMD in persons over the age of 40 years in sub-Saharan Africa (SSA). We developed a population-based cross-sectional study of disease burden and phenotype in Africans, across six centres in SSA. These centres are in West Africa (Nanoro, Burkina Faso, and Navrongo, Ghana), in East Africa (Nairobi, Kenya) and in South Africa (Agincourt, Dikgale and Soweto). A total of 10,702 individuals between the ages of 40 and 60 years were recruited into the study across the six centres, plus an additional 1021 participants over the age of 60 years from the Agincourt centre. We collected socio-demographic, anthropometric, medical history, diet, physical activity, fat distribution and alcohol/tobacco consumption data from participants. Blood samples were collected for disease-related biomarker assays, and genomic DNA extraction for genome-wide association studies. Urine samples were collected to assess kidney function. The study provides base-line data for the development of a series of cohorts with a second wave of data collection in Phase 2 of the study. These data will provide valuable insights into the genetic and environmental influences on CMD on the African continent.
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- 2018
4. A randomized clinical trial comparing metabolic parameters after 48 weeks of standard‐ and low‐dose stavudine therapy and tenofovir disoproxil fumarate therapy in HIV‐infected South African patients
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Menezes, CN, primary, Crowther, NJ, additional, Duarte, R, additional, Van Amsterdam, D, additional, Evans, D, additional, Dickens, C, additional, Dix‐Peek, T, additional, Rassool, M, additional, Prinsloo, A, additional, Raal, F, additional, and Sanne, I, additional
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- 2013
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5. Lipid accumulation and alkaline phosphatase activity in human preadipocytes isolated from different body fat depots
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Ali, AT, primary, Ferris, WF, additional, Penny, CB, additional, Van der Merwe, M-T, additional, Jacobson, BF, additional, Paiker, JE, additional, and Crowther, NJ, additional
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- 2013
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6. The early effects of stavudine compared with tenofovir on adipocyte gene expression, mitochondrial DNA copy number and metabolic parameters in South African HIV-infected patients: a randomized trial
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Menezes, CN, primary, Duarte, R, additional, Dickens, C, additional, Dix-Peek, T, additional, Van Amsterdam, D, additional, John, M-A, additional, Ive, P, additional, Maskew, M, additional, MacPhail, P, additional, Fox, MP, additional, Raal, F, additional, Sanne, I, additional, and Crowther, NJ, additional
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- 2012
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7. The impact of insulin resistance, gender, genes, glucocorticoids and ethnicity on body fat distribution
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Crowther, NJ, primary and Ferris, WF, additional
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- 2010
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8. Factors predisposing to obesity: a review of the literature
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Ali, AT, primary and Crowther, NJ, additional
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- 2010
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9. Factors predisposing to obesity: a review of the literature
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Ali, AT, primary and Crowther, NJ, additional
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- 2009
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10. Weight-related differences in glucose metabolism and free fatty acid production in two South African population groups
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Punyadeera, C, primary, van der Merwe, M-T, additional, Crowther, NJ, additional, Toman, M, additional, Immelman, AR, additional, Schlaphoff, GP, additional, and Gray, IP, additional
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- 2001
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11. Evidence for insulin resistance in black women from South Africa
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van der Merwe, M-T, primary, Crowther, NJ, additional, Schlaphoff, GP, additional, Gray, IP, additional, Joffe, BI, additional, and Lönnroth, PN, additional
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- 2000
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12. Free fatty acids and insulin levels—relationship to leptin levels and body composition in various patient groups from South Africa
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van der Merwe, M-T, primary, Panz, VR, additional, Crowther, NJ, additional, Schlaphoff, GP, additional, Gray, IP, additional, Froguel, P, additional, Joffe, BI, additional, and Lönnroth, PN, additional
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- 1999
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13. The early effects of stavudine compared with tenofovir on adipocyte gene expression, mitochondrial DNA copy number and metabolic parameters in South African HIV-infected patients: a randomized trial.
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Menezes, CN, Duarte, R, Dickens, C, Dix‐Peek, T, Van Amsterdam, D, John, M‐A, Ive, P, Maskew, M, MacPhail, P, Fox, MP, Raal, F, Sanne, I, and Crowther, NJ
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ANALYSIS of variance ,BLACK people ,COMPARATIVE studies ,FAT cells ,GENE expression ,HIV infections ,INSULIN resistance ,MITOCHONDRIA ,POLYMERASE chain reaction ,RESEARCH funding ,STATISTICAL sampling ,STATISTICS ,RANDOMIZED controlled trials ,STAVUDINE ,DATA analysis software ,TENOFOVIR ,DESCRIPTIVE statistics ,PHARMACODYNAMICS - Abstract
Objectives Stavudine is being phased out because of its mitochondrial toxicity and tenofovir ( TDF) is recommended as part of first-line highly active antiretroviral therapy ( HAART) in South Africa. A prospective, open-label, randomized controlled trial comparing standard- and low-dose stavudine with TDF was performed to assess early differences in adipocyte mtDNA copy number, gene expression and metabolic parameters in Black South African HIV-infected patients. Methods Sixty patients were randomized 1:1:1 to either standard-dose (30-40 mg) or low-dose (20-30 mg) stavudine or TDF (300 mg) each combined with lamivudine and efavirenz. Subcutaneous fat biopsies were obtained at weeks 0 and 4. Adipocyte mt DNA copies/cell and gene expression were measured using quantitative polymerase chain reaction ( qPCR). Markers of inflammation and lipid and glucose metabolism were also assessed. Results A 29% and 32% decrease in the mean mtDNA copies/cell was noted in the standard-dose ( P < 0.05) and low-dose stavudine ( P < 0.005) arms, respectively, when compared with TDF at 4 weeks. Nuclear respiratory factor-1 ( NRF1) and mitochondrial cytochrome B ( MTCYB) gene expression levels were affected by stavudine, with a significantly ( P < 0.05) greater fall in expression observed with the standard, but not the low dose compared with TDF. No significant differences were observed in markers of inflammation and lipid and glucose metabolism. Conclusions These results demonstrate early mitochondrial depletion among Black South African patients receiving low and standard doses of stavudine, with preservation of gene expression levels, except for NRF1 and MTCYB, when compared with patients on TDF. [ABSTRACT FROM AUTHOR]
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- 2013
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14. Letter to the Editor
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Crowther, NJ, primary, Georgeson, Margaret A, additional, and Dunford, Cheryl, additional
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- 1992
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15. Deriving an optimal threshold of waist circumference for detecting cardiometabolic risk in sub-Saharan Africa
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Ekoru, K, Murphy, GAV, Young, EH, Delisle, H, Jerome, CS, Assah, F, Longo-Mbenza, B, Nzambi, JPD, On'Kin, JBK, Buntix, F, Muyer, MC, Christensen, DL, Wesseh, CS, Sabir, A, Okafor, C, Gezawa, ID, Puepet, F, Enang, O, Raimi, T, Ohwovoriole, E, Oladapo, OO, Bovet, P, Mollentze, W, Unwin, N, Gray, WK, Walker, R, Agoudavi, K, Siziya, S, Chifamba, J, Njelekela, M, Fourie, CM, Kruger, S, Schutte, AE, Walsh, C, Gareta, D, Kamali, A, Seeley, J, Norris, SA, Crowther, NJ, Pillay, D, Kaleebu, P, Motala, AA, and Sandhu, MS
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Clinical ,Clinical Research ,Prevention ,Public Health ,Obesity ,3. Good health ,1117 Public Health and Health Services ,Nutrition - Abstract
BACKGROUND: Waist circumference (WC) thresholds derived from western populations continue to be used in sub-Saharan Africa (SSA) despite increasing evidence of ethnic variation in the association between adiposity and cardiometabolic disease and availability of data from African populations. We aimed to derive a SSA-specific optimal WC cut-point for identifying individuals at increased cardiometabolic risk. METHODS: We used individual level cross-sectional data on 24 181 participants aged ⩾15 years from 17 studies conducted between 1990 and 2014 in eight countries in SSA. Receiver operating characteristic curves were used to derive optimal WC cut-points for detecting the presence of at least two components of metabolic syndrome (MS), excluding WC. RESULTS: The optimal WC cut-point was 81.2 cm (95% CI 78.5-83.8 cm) and 81.0 cm (95% CI 79.2-82.8 cm) for men and women, respectively, with comparable accuracy in men and women. Sensitivity was higher in women (64%, 95% CI 63-65) than in men (53%, 95% CI 51-55), and increased with the prevalence of obesity. Having WC above the derived cut-point was associated with a twofold probability of having at least two components of MS (age-adjusted odds ratio 2.6, 95% CI 2.4-2.9, for men and 2.2, 95% CI 2.0-2.3, for women). CONCLUSION: The optimal WC cut-point for identifying men at increased cardiometabolic risk is lower (⩾81.2 cm) than current guidelines (⩾94.0 cm) recommend, and similar to that in women in SSA. Prospective studies are needed to confirm these cut-points based on cardiometabolic outcomes.International Journal of Obesity advance online publication, 31 October 2017; doi:10.1038/ijo.2017.240.
16. Influence of catch-up growth on glucose tolerance and beta-cell function in 7-year-old children: results from the birth to twenty study.
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Crowther NJ, Cameron N, Trusler J, Toman M, Norris SA, and Gray IP
- Abstract
OBJECTIVE: The aim of this study was to investigate the effect of catch-up growth occurring at different stages of childhood on glucose levels and beta-cell function at 7 years of age. METHODS: Oral glucose tolerance tests were performed on 152 7-year-old children. Anthropometric data were available from birth to 7 years of age. Children were split into catch-up, catch-down, and normal-growth groups on the basis of growth rates between birth and 1 year, birth and 5 years, and birth and 7 years. Fasting and 30- and 120-minute blood samples collected during the oral glucose tolerance tests were assayed for glucose, insulin, proinsulin, and des-31,32-proinsulin levels, and area-under-the-curve values were calculated. RESULTS: Children with catch-up growth between birth and 5 years or birth and 7 years had greater area-under-the-curve insulin levels than the children with catch-down growth. Children with catch-up growth only between birth and 7 years exhibited higher proinsulin levels and a greater insulin secretory response to glucose than those who experienced catch-up growth between both birth and 1 year and birth and 7 years of age. Low birth weight children with no catch-up growth between birth and 7 years had the highest glucose and lowest insulinogenic index levels, whereas children with high birth weight and catch-up growth had the highest insulin levels. CONCLUSIONS: Extremes of birth weight in conjunction with extremes of postnatal growth are all detrimental to childhood metabolism. The negative metabolic effects of catch-up growth between birth and 7 years may be attenuated if catch-up growth also occurs between birth and 1 year of age. [ABSTRACT FROM AUTHOR]
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- 2008
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17. Engineered antibodies: a new tool for use in diabetes research.
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Padoa CJ and Crowther NJ
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A revolution has occurred in the field of antibody engineering since Kohler and Milstein described a technique for the production of monoclonal antibodies in 1975. Their paper paved the way for future discoveries which have culminated in the use of recombinant antibody fragments in the treatment of diseases and their widespread use in research. This article will highlight some of these advances (scFv and Fab production, phage and ribosome display) as well as looking at the different uses of these recombinant antibody fragments in research and the treatment/diagnosis of disease. In particular, we will focus on the role of rFabs in mapping disease specific epitopes in diabetic patients and the promise this holds for the future. The methodology of genetic engineering has made it possible to produce tailor-made antibodies which do not depend on animal vehicles. The applications of these rFab are widespread. Many developments in diabetes diagnostics have come through innovations in antibody technology. The further development of techniques for producing recombinant antibodies will ultimately lead to even greater improvements in therapeutics and diagnostics for a number of different human diseases. [ABSTRACT FROM AUTHOR]
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- 2006
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18. Assessing compliance with national guidelines in diabetes care: A study leveraging data from south Africa's National Health Laboratory Service (NHLS).
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Brennan AT, Kileel EM, Fox MP, George JA, Khoza S, Rosen S, Raal F, Hibberd P, Chetty K, Mlisana K, Bor J, and Crowther NJ
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Diabetes is a major global health issue. We evaluated compliance to laboratory-based management guidelines for diabetes (type 1 and 2), essential for effective treatment and reducing diabetes-related morbidity and mortality. Our study utilized South Africa's National Health Laboratory Services (NHLS) data, focusing on patients from birth to age 80 years who underwent initial diabetes laboratory testing between January 1, 2012-January 1, 2016. Patients were categorized into type 1 (<30 years) or type 2 (≥30-80 years) diabetes based on age at first diabetes test. National diabetes guidelines recommend blood glucose to be checked every three-six months post laboratory-diagnosis. We employed a sharp regression discontinuity design to estimate the effect of a laboratory-diagnosis of diabetes on the likelihood of having a follow-up laboratory test 24 months post-diagnosis. Among patients with type 2 diabetes, the probability of a diabetes follow-up laboratory test within 24 months was 52.4% for patients presenting above the diabetes diagnosis threshold vs 31.1% for those presenting below. Although the likelihood of repeat testing rose with higher HbA1c and glucose levels, at the diagnostic threshold there was no clinically meaningful difference (risk difference: -2.2%, 95% CI: -3.3%, -1.2%). These results were consistent among patients with type 1 diabetes, those living with and without HIV, and healthcare setting. In a national laboratory cohort, diabetes laboratory-diagnosis did not lead to increased monitoring as recommended in national guidelines. Strategies to improve patient education, healthcare provider communication, and healthcare system support are essential to enhance guideline compliance and overall diabetes management., Competing Interests: Professor Frederick Raal has received research grants, honoraria, and consulting fees for professional input and/or delivered lectures from Amgen, MSD, Novartis, Sanofi, Regeneron, Ultragenyx and LIB Therapeutics unrelated to the manuscript. All other authors have declared that no competing interests exist. There are no patents, products in development or marketed products associated with this research to declare. This does not alter our adherence to PLOS ONE policies on sharing data and materials., (Copyright: © 2024 Brennan et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2024
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19. The association of menopause with cardiometabolic disease risk factors in women living with and without HIV in sub-Saharan Africa: Results from the AWI-Gen 1 study.
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Chikwati RP, Jaff NG, Mahyoodeen NG, Micklesfield LK, Ramsay M, Gómez-Olivé FX, Mohamed SF, Choma SSR, George JA, and Crowther NJ
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- Humans, Female, Middle Aged, Cross-Sectional Studies, Africa South of the Sahara epidemiology, Prevalence, Adult, Risk Factors, Cardiovascular Diseases epidemiology, Cardiovascular Diseases etiology, Postmenopause, Premenopause, Metabolic Syndrome epidemiology, Body Mass Index, Blood Pressure, HIV Infections complications, HIV Infections epidemiology, Menopause, Cardiometabolic Risk Factors
- Abstract
Background: Menopause and HIV are associated with cardiometabolic disease. In sub-Saharan Africa there is a growing population of midlife women living with HIV and a high prevalence of cardiometabolic disease., Objectives: The aim of this study was to determine whether menopause and HIV were associated with cardiometabolic disease risk factors in a population of midlife sub-Saharan African women., Study Design: This was a cross-sectional comparison of cardiometabolic disease risk factors between 944 premenopausal women (733 living without HIV and 211 living with HIV) and 1135 postmenopausal women (932 living without HIV and 203 living with HIV) in sub-Saharan Africa., Main Outcome Measures: Anthropometric and cardiometabolic variables were compared between pre- and postmenopausal women living without HIV and between pre- and postmenopausal women living with HIV and between women living without HIV and women living with HIV., Results: The prevalence of HIV was 19.9 %. Age at menopause was lower in women living with HIV than in women living without HIV (48.1 ± 5.1 vs 50.9 ± 4.7 years, p < 0.001). Women living with HIV and receiving efavirenz-based antiretroviral therapy had a lower body mass index (BMI), hip circumference, blood pressure and carotid intima media thickness but higher triglyceride levels and insulin resistance than women living without HIV. Antiretroviral therapy-naïve women living with HIV had lower HDL-cholesterol than women living without HIV. In this study, menopause was associated with higher LDL-C levels, regardless of HIV status., Conclusion: The high prevalence of obesity and related cardiometabolic disease risk factors in these midlife sub-Saharan African women is not related to the menopausal transition. The association of cardiometabolic disease risk factors with HIV and antiretroviral therapy is complex and requires further investigation in longitudinal studies, as does the negative association of age at final menstrual period with HIV., Competing Interests: Declaration of competing interest The authors declare that they have no competing interest., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)
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- 2024
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20. SHBG, Free Testosterone, and Type 2 Diabetes Risk in Middle-aged African Men: A Longitudinal Study.
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Seipone ID, Mendham AE, Storbeck KH, Oestlund I, Kufe CN, Chikowore T, Masemola M, Crowther NJ, Kengne AP, Norris S, Olsson T, Brown T, Micklesfield LK, and Goedecke JH
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Objectives: To investigate longitudinal changes in SHBG and free testosterone (free T) levels among Black middle-aged African men, with and without coexistent HIV, and explore associations with incident dysglycaemia and measures of glucose metabolism., Design: This longitudinal study enrolled 407 Black South African middle-aged men, comprising primarily 322 men living without HIV (MLWOH) and 85 men living with HIV (MLWH), with normal fasting glucose at enrollment. Follow-up assessments were conducted after 3.1 ± 1.5 years., Methods: At baseline and follow-up, SHBG, albumin, and total testosterone were measured and free T was calculated. An oral glucose tolerance test at follow-up determined dysglycaemia (impaired fasting glucose, impaired glucose tolerance, type 2 diabetes) and glucose metabolism parameters including insulin sensitivity (Matsuda index), insulin resistance (homeostasis model assessment of insulin resistance), and beta(β)-cell function (disposition index). The primary analysis focussed on MLWOH, with a subanalysis on MLWH to explore whether associations in MLWOH differed from MLWH., Results: The prevalence of dysglycaemia at follow-up was 17% (n = 55) in MLWOH. Higher baseline SHBG was associated with a lower risk of incident dysglycaemia (odds ratio 0.966; 95% confidence interval 0.945-0.987) and positively associated with insulin sensitivity (β = 0.124, P < .001) and β-cell function (β = 0.194, P = .001) at follow-up. Free T did not predict dysglycaemia. In MLWH, dysglycaemia prevalence at follow-up was 12% (n = 10). Neither baseline SHBG nor free T were associated with incident dysglycaemia and glucose metabolism parameters in MLWH., Conclusion: SHBG levels predict the development of dysglycaemia in middle-aged African men but do not exhibit the same predictive value in MLWH., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society.)
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- 2024
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21. Regional adiposity and insulin sensitivity - interactions with menopause and HIV in middle-aged Black African women.
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Masemola M, Mendham AE, Micklesfield LK, Pheiffer C, Hawley J, Kengne AP, Chikowore T, Kufe CN, Crowther NJ, Norris S, Storbeck KH, Olsson T, Karpe F, and Goedecke JH
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Objective: To explore depot-specific functional aspects of adipose tissue, examining the putative role for menopause and HIV status on insulin sensitivity (SI) and beta-cell function in Black South African women., Methods: Women (n = 92) from the Middle-Aged Soweto Cohort, including premenopausal HIV-negative (n = 21); premenopausal women living with HIV (WLWH; n = 11); postmenopausal HIV-negative (n = 42); postmenopausal WLWH (n = 18) underwent the following tests: body composition (dual energy x-ray absorptiometry); fasting bloods for sex hormones, inflammation and adipokines; frequently sampled intravenous glucose tolerance test for SI and beta-cell function (disposition index, DI); abdominal (aSAT) and gluteal subcutaneous adipose tissue (gSAT) biopsies for cell size and mRNA expression of adipokines, inflammation, and estrogen receptors [ER]., Results: Depot-specific associations between gene expression and insulin parameters did not differ by HIV or menopause status. Pooled analysis showed significant models for SI (P = 0.002) and DI (P = 0.003). Higher SI was associated with lower leptin and CD11c expression in aSAT and higher adiponectin in gSAT. Higher DI was associated with higher aSAT and gSAT expression of adiponectin, LPL, ERα, and PPARγ, and lower leptin in aSAT. WLWH had higher expression of adiponectin and lower expression of leptin in both aSAT (P = 0.002 and P = 0.005) and gSAT (P = 0.004 and P = 0.002), respectively, and a larger proportion of smaller cells in aSAT (P < 0.001)., Conclusion: Insulin sensitivity and beta cell function were distinctively associated with aSAT and gSAT. While menopause did not influence these relationships, HIV had a significant effect on adipose tissue, characterised by variations in cell size distribution and transcript levels within the depots., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com. See the journal About page for additional terms.)
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- 2024
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22. Does Engagement in HIV Care Affect Screening, Diagnosis, and Control of Noncommunicable Diseases in Sub-Saharan Africa? A Systematic Review and Meta-analysis.
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Kileel EM, Zheng A, Bor J, Fox MP, Crowther NJ, George JA, Khoza S, Rosen S, Venter WDF, Raal F, Hibberd P, and Brennan AT
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- Humans, Africa South of the Sahara epidemiology, Anti-HIV Agents therapeutic use, Cardiovascular Diseases epidemiology, Cardiovascular Diseases prevention & control, Cardiovascular Diseases diagnosis, Diabetes Mellitus epidemiology, Diabetes Mellitus diagnosis, Hypertension drug therapy, Hypertension epidemiology, Hypertension diagnosis, HIV Infections drug therapy, HIV Infections diagnosis, HIV Infections epidemiology, Mass Screening, Noncommunicable Diseases epidemiology, Noncommunicable Diseases prevention & control
- Abstract
Low- and middle-income countries are facing a growing burden of noncommunicable diseases (NCDs). Providing HIV treatment may provide opportunities to increase access to NCD services in under-resourced environments. We conducted a systematic review and meta-analysis to evaluate whether use of antiretroviral therapy (ART) was associated with increased screening, diagnosis, treatment, and control of diabetes, hypertension, chronic kidney disease, or cardiovascular disease among people living with HIV in sub-Saharan Africa (SSA). A comprehensive search of electronic literature databases for studies published between 01 January 2011 and 31 December 2022 yielded 26 studies, describing 13,570 PLWH in SSA, 61% of whom were receiving ART. Random effects models were used to calculate summary odds ratios (ORs) of the risk of diagnosis by ART status and corresponding 95% confidence intervals (95% CIs), where appropriate. ART use was associated with a small but imprecise increase in the odds of diabetes diagnosis (OR 1.07; 95% CI 0.71, 1.60) and an increase in the odds of hypertension diagnosis (OR 2.10, 95% CI 1.42, 3.09). We found minimal data on the association between ART use and screening, treatment, or control of NCDs. Despite a potentially higher NCD risk among PLWH and regional efforts to integrate NCD and HIV care, evidence to support effective care integration models is lacking., (© 2024. The Author(s).)
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- 2024
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23. Prevalence of and Risk Factors for Peripheral Artery Disease in Rural South Africa: A Cross-Sectional Analysis of the HAALSI Cohort.
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Beidelman ET, Rosenberg M, Wade AN, Crowther NJ, and Kalbaugh CA
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- Adult, Humans, Cross-Sectional Studies, South Africa epidemiology, Prevalence, Risk Factors, Ankle Brachial Index, Peripheral Arterial Disease diagnosis, Peripheral Arterial Disease epidemiology
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Background: The burden of peripheral artery disease (PAD) is increasing in low- and middle-income countries. Existing literature from sub-Saharan Africa is limited and lacks population-representative estimates. We estimated the burden and risk factor profile of PAD for a rural South African population., Methods and Results: We used data from 1883 participants from a rural, low-income cohort of South African adults aged 40 to 69 years with available ankle-brachial index measurements. We defined clinical PAD as ankle-brachial index ≤0.90 or >1.40, and borderline PAD as ankle-brachial index >0.90 and ≤1.00. We compared the distribution of sociodemographic variables, biomarkers, and comorbidities across PAD classifications. To identify associated factors, we calculated unadjusted and age-sex-adjusted prevalence ratios (PRs) with log-binomial models. Overall, 6.6% (95% CI, 5.6-7.7) of the sample met the diagnostic criteria for clinical PAD, while 44.7% (95% CI, 42.4-47.0) met the diagnostic criteria for borderline PAD. Age (PR: 1.9 [95% CI, 1.2-3.1] for ages 50-59 years compared with 40-49 years; PR: 2.5 [95% CI, 1.5-4.0] for ages 60-69 years compared with 40-49 years); diagnosed hypertension (PR: 1.53 [95% CI, 1.08-2.17]); and C-reactive protein (PR: 1.08 [95% CI, 1.03-1.12]) were associated with increased prevalence of clinical PAD. All other examined factors were not significantly associated with clinical PAD., Conclusions: We found high PAD prevalence for younger age groups compared with previous research and a lack of statistical evidence for the influence of traditional risk factors for this rural, low-income population. Future research should focus on identifying the underlying risk factors for PAD in this setting. South African policymakers and clinicians should consider expanded screening for early PAD detection in rural areas.
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- 2024
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24. The association of menopause with cardiometabolic disease risk factors in low- and middle-income countries: a systematic review and meta-analyses.
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Chikwati RP, Chikowore T, Mahyoodeen NG, Jaff NG, George JA, and Crowther NJ
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- Female, Humans, Developing Countries, Premenopause, Risk Factors, Metabolic Syndrome epidemiology, Cardiovascular Diseases epidemiology
- Abstract
Importance: Menopause is an integral part of women's health, and studies in high-income countries have shown an increase in cardiometabolic disease (CMD) risk factors in postmenopausal compared with premenopausal women. However, to date, no study has combined and assessed such studies across low- and middle-income countries. This would better inform early monitoring and intervention strategies for reducing CMD risk factor levels in midlife women in these regions., Objective: This study aimed to evaluate evidence from the literature on differences in CMD risk factors between premenopausal and postmenopausal midlife women living in low- and middle-income countries., Evidence Review: A systematic review with meta-analysis of original articles of all study designs from the databases PubMed, PubMed Central, Scopus, and ISI Web of Science was conducted from conception until April 24, 2023. Studies that met the inclusion criteria were included in the analysis. Quality assessment of the articles was done using the Newcastle-Ottawa Scale, adapted for each study design. The study protocol was registered with the International Prospective Register of Systematic Reviews and adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis. For the meta-analysis, fixed-effects models were used to pool the odds ratios (OR), as measures of association., Findings: Our search identified 4,849 relevant articles: 44 for the systematic review and 16 for the meta-analysis, in accordance with our inclusion criteria. Compared with premenopausal women, the postmenopausal stage was associated with metabolic syndrome (OR, 1.18 [95% CI, 1.11-1.27]), high waist-to-hip ratio (OR, 1.22 [95% CI, 1.12-1.32]), hypertension (OR, 1.10 [95% CI, 1.04-1.16]), elevated triglycerides (OR, 1.16 [95% CI, 1.11-1.21]), and elevated plasma glucose (OR, 1.21 [95% CI, 1.15-1.28])., Conclusions and Relevance: This study confirmed that CMD risk factors are present at higher levels in postmenopausal than premenopausal women. This demonstrates an urgent need for public health policies that focus on early monitoring and interventions targeted at reducing CMD risk and related adverse outcomes in midlife women in these nations., Competing Interests: Financial disclosure/conflicts of interest: Nicole G. Jaff receives funding from the International Menopause Society and the South African Menopause Society. Tinashe Chikowore is an international training fellow supported by the Wellcome Trust grant (214205/Z/18/Z). The other authors have nothing to disclose., (Copyright © 2023 by The Menopause Society.)
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- 2024
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25. Gaps in the type 2 diabetes care cascade: a national perspective using South Africa's National Health Laboratory Service (NHLS) database.
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Brennan AT, Lauren E, Bor J, George JA, Chetty K, Mlisana K, Dai A, Khoza S, Rosen S, Stokes AC, Raal F, Hibberd P, Alexanian SM, Fox MP, and Crowther NJ
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- Humans, Blood Glucose, Glycated Hemoglobin, South Africa epidemiology, Diabetes Mellitus, Type 2 diagnosis, Diabetes Mellitus, Type 2 epidemiology, Diabetes Mellitus, Type 2 therapy, HIV Infections diagnosis, HIV Infections epidemiology, HIV Infections therapy
- Abstract
Background: Research out of South Africa estimates the total unmet need for care for those with type 2 diabetes mellitus (diabetes) at 80%. We evaluated the care cascade using South Africa's National Health Laboratory Service (NHLS) database and assessed if HIV infection impacts progression through its stages., Methods: The cohort includes patients from government facilities with their first glycated hemoglobin A1c (HbA1c) or plasma glucose (fasting (FPG); random (RPG)) measured between January 2012 to March 2015 in the NHLS. Lab-diagnosed diabetes was defined as HbA1c ≥ 6.5%, FPG ≥ 7.0mmol/l, or RPG ≥ 11.1mmol/l. Cascade stages post diagnosis were retention-in-care and glycaemic control (defined as an HbA1c < 7.0% or FPG < 8.0mmol/l or RPG < 10.0mmol/l) over 24-months. We estimated gaps at each stage nationally and by people living with HIV (PLWH) and without (PLWOH)., Results: Of the 373,889 patients tested for diabetes, 43.2% had an HbA1c or blood glucose measure indicating a diabetes diagnosis. Amongst those with lab-diagnosed diabetes, 30.9% were retained-in-care (based on diabetes labs) and 8.7% reached glycaemic control by 24-months. Prevalence of lab-diagnosed diabetes in PLWH was 28.6% versus 47.3% in PLWOH. Among those with lab-diagnosed diabetes, 34.3% of PLWH were retained-in-care versus 30.3% PLWOH. Among people retained-in-care, 33.8% of PLWH reached glycaemic control over 24-months versus 28.6% of PLWOH., Conclusions: In our analysis of South Africa's NHLS database, we observed that 70% of patients diagnosed with diabetes did not maintain in consistent diabetes care, with fewer than 10% reaching glycemic control within 24 months. We noted a disparity in diabetes prevalence between PLWH and PLWOH, potentially linked to different screening methods. These differences underscore the intricacies in care but also emphasize how HIV care practices could guide better management of chronic diseases like diabetes. Our results underscore the imperative for specialized strategies to bolster diabetes care in South Africa., (© 2023. The Author(s).)
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- 2023
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26. Genome-wide association study meta-analysis of blood pressure traits and hypertension in sub-Saharan African populations: an AWI-Gen study.
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Singh S, Choudhury A, Hazelhurst S, Crowther NJ, Boua PR, Sorgho H, Agongo G, Nonterah EA, Micklesfield LK, Norris SA, Kisiangani I, Mohamed S, Gómez-Olivé FX, Tollman SM, Choma S, Brandenburg JT, and Ramsay M
- Subjects
- Humans, Blood Pressure genetics, Black People genetics, Uganda, Polymorphism, Single Nucleotide, Genome-Wide Association Study, Hypertension epidemiology, Hypertension genetics
- Abstract
Most hypertension-related genome-wide association studies (GWASs) focus on non-African populations, despite hypertension (a major risk factor for cardiovascular disease) being highly prevalent in Africa. The AWI-Gen study GWAS meta-analysis for blood pressure (BP)-related traits (systolic and diastolic BP, pulse pressure, mean-arterial pressure and hypertension) from three sub-Saharan African geographic regions (N = 10,775), identifies two novel genome-wide significant signals (p < 5E-08): systolic BP near P2RY1 (rs77846204; intergenic variant, p = 4.95E-08) and pulse pressure near LINC01256 (rs80141533; intergenic variant, p = 1.76E-08). No genome-wide signals are detected for the AWI-Gen GWAS meta-analysis with previous African-ancestry GWASs (UK Biobank (African), Uganda Genome Resource). Suggestive signals (p < 5E-06) are observed for all traits, with 29 SNPs associating with more than one trait and several replicating known associations. Polygenic risk scores (PRSs) developed from studies on different ancestries have limited transferability, with multi-ancestry PRS providing better prediction. This study provides insights into the genetics of BP variation in African populations., (© 2023. The Author(s).)
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- 2023
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27. Does engagement in HIV care affect screening, diagnosis, and control of noncommunicable diseases in sub-Saharan Africa? A systematic review and meta-analysis.
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Kileel EM, Zheng A, Bor J, Fox MP, Crowther NJ, George JA, Khoza S, Rosen S, Venter WD, Raal F, Hibberd P, and Brennan AT
- Abstract
Objective: Low- and middle-income countries are facing a growing burden of noncommunicable diseases (NCDs). Providing HIV treatment may also provide opportunities to increase access to NCD services in under-resourced environments. We sought to investigate whether reported use of antiretroviral therapy (ART) was associated with increased screening, diagnosis, treatment, and/or control of diabetes, hypertension, chronic kidney disease, or cardiovascular disease among people living with HIV (PLWH) in sub-Saharan Africa (SSA)., Design: Systematic review and meta-analysis., Methods: We searched 10 electronic literature databases for studies published between 01 January 2011 and 31 December 2022 using a comprehensive search strategy. We sought studies reporting on screening, diagnosis, treatment, and/or control of NCDs of interest by ART use among non-pregnant adults with HIV ≥16 years of age in SSA. Random effects models were used to calculate summary odds ratios (ORs) of the risk of diagnosis by ART status and corresponding 95% confidence intervals (95% CIs), where appropriate., Results: Twenty-six studies, describing 13,570 PLWH in SSA, 61% of whom were receiving ART, were included. ART use was associated with a small but imprecise increase in the odds of diabetes diagnosis (OR: 1.07; 95% CI: 0.71, 1.60) and an increase in the odds of hypertension diagnosis (OR: 2.10, 95% CI: 1.42, 3.09). We found minimal data on the association between ART use and screening, treatment, or control of NCDs., Conclusion: Despite a potentially higher NCD risk among PLWH and regional efforts to integrate NCD and HIV care, evidence to support effective care integration models is lacking., Competing Interests: This work was supported by National Institute of Diabetes and Digestive and Kidney Diseases 1K01DK116929-01A1 (ATB and EMK) and the Bill & Melinda Gates Foundation INV-031690 (SR). For the remaining authors none were declared.
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- 2023
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28. Cardiometabolic disease risk factors in pre- and postmenopausal women from four sub-Saharan African countries: A cross-sectional study.
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Chikwati RP, Mahyoodeen NG, Jaff NG, Ramsay M, Micklesfield LK, Wade AN, Agongo G, Asiki G, Choma SSR, Boua PR, George JA, and Crowther NJ
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- Humans, Female, Cross-Sectional Studies, Carotid Intima-Media Thickness, South Africa epidemiology, Kenya, Risk Factors, Postmenopause, Cardiovascular Diseases epidemiology, Cardiovascular Diseases etiology
- Abstract
Objective: To compare the risk factors for cardiometabolic disease between pre- and postmenopausal women from four sub-Saharan African countries., Study Design: This cross-sectional study included 3609 women (1740 premenopausal and 1869 postmenopausal) from sites in Ghana (Navrongo), Burkina Faso (Nanoro), Kenya (Nairobi), and South Africa (Soweto and Dikgale). Demographic, anthropometric and cardiometabolic variables were compared between pre- and postmenopausal women, within and across sites using multivariable regression analyses. The sites represent populations at different stages of the health transition, with those in Ghana and Burkina Faso being rural, whilst those in Kenya and South Africa are more urbanised., Main Outcome Measures: Anthropometric and cardiometabolic variables., Results: The prevalence rates of risk factors for cardiometabolic disease were higher in South (Soweto and Dikgale) and East (Nairobi) Africa than in West Africa (Nanoro and Navrongo), irrespective of menopausal status. Regression models in combined West African populations demonstrated that postmenopausal women had a larger waist circumference (β = 1.28 (95 % CI: 0.58; 1.98) cm), log subcutaneous fat (β =0.15 (0.10; 0.19)), diastolic (β = 3.04 (1.47; 4.62) mm Hg) and log systolic (β = 0.04 (0.02; 0.06)) blood pressure, log carotid intima media thickness (β = 0.03 (0.01; 0.06)), low-density lipoprotein cholesterol (β = 0.14 (0.04; 0.23) mmol/L) and log triglyceride (β= 0.10 (0.04; 0.16)) levels than premenopausal women. No such differences were observed in the South and East African women., Conclusions: Menopause-related differences in risk factors for cardiometabolic disease were prominent in West but not East or South African study sites. These novel findings should inform cardiometabolic disease prevention strategies in midlife women specific to rural and urban and peri-urban locations in sub-Saharan Africa., Competing Interests: Declaration of competing interest The authors declare that they have no competing interest., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)
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- 2023
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29. The Impact of Human Immunodeficiency Virus and Menopause on Bone Mineral Density: A Longitudinal Study of Urban-Dwelling South African Women.
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Madanhire T, Goedecke JH, Ward KA, Jaff N, Crowther NJ, Norris S, Ferrand RA, Rehman AM, Micklesfield LK, and Gregson CL
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- Female, Humans, Middle Aged, Bone Density, HIV, Longitudinal Studies, Lumbar Vertebrae, Menopause, South Africa epidemiology, Urban Population, HIV Infections complications, Osteoporosis, Postmenopausal
- Abstract
An estimated 25% of South African women live with human immunodeficiency virus (HIV). Antiretroviral therapy roll-out has improved life expectancy, so many more women now reach menopause. We aimed to quantify changes in bone mineral density (BMD) during the menopausal transition in urban-dwelling South African women with and without HIV and determine whether HIV infection modified the effect of menopause on BMD changes. A 5-year population-based longitudinal study recruited women aged 40-60 years residing in Soweto and collected demographic and clinical data, including HIV status, anthropometry, and BMD, at baseline and at 5-year follow-up. All women were staged as pre-, peri-, or postmenopausal at both time points. Multivariable linear regression assessed relationships and interactions between HIV infection, menopause, and change in BMD. At baseline, 450 women had mean age 49.5 (SD 5.7) years, 65 (14.4%) had HIV, and 140 (31.1%), 119 (26.4%), and 191 (42.4%) were pre-, peri-, and postmenopausal, respectively; 34/205 (13.6%) women ≥50 years had a total hip (TH) or lumbar spine (LS) T-score ≤ -2.5. At follow-up 38 (8.4%), 84 (18.7%), and 328 (72.9%) were pre-, peri-, and postmenopausal. Those with HIV at baseline lost more total body (TB) BMD (mean difference -0.013 [95% confidence interval -0.026, -0.001] g/cm
2 , p = 0.040) and gained more weight 1.96 [0.32, 3.60] kg; p = 0.019 than HIV-uninfected women. After adjusting for age, baseline weight, weight change, and follow-up time, the transition from pre- to postmenopause was associated with greater TB BMD losses in women with HIV (-0.092 [-0.042, -0.142] g/cm2 ; p = 0.001) than without HIV (-0.038 [-0.016, -0.060] g/cm2 , p = 0.001; interaction p = 0.034). Similarly, in women who were postmenopausal at both time points, those with HIV lost more TB BMD (-0.070 [-0.031, -0.108], p = 0.001) than women without HIV (-0.036 [-0.015, -0.057], p = 0.001, interaction p = 0.049). Findings were consistent but weaker at the LS and TH. Menopause-related bone loss is greater in women with HIV, suggesting women with HIV may be at greater risk of osteoporotic fractures. HIV services should consider routine bone health assessment in midlife women as part of long-term HIV care delivery. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR)., (© 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).)- Published
- 2023
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30. Diabetes care cascade and associated factors in 10 700 middle-aged adults in four sub-Saharan African countries: a cross-sectional study.
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Wade AN, Maposa I, Agongo G, Asiki G, Boua P, Choma SSR, Gómez-Olivé FX, Maimela E, Micklesfield LK, Mohamed SF, Nonterah EA, Norris SA, Sorgho H, Ramsay M, and Crowther NJ
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- Middle Aged, Adult, Humans, Cross-Sectional Studies, Blood Glucose, Africa South of the Sahara epidemiology, Prevalence, Diabetes Mellitus epidemiology, Diabetes Mellitus therapy, Hypertension epidemiology
- Abstract
Objectives: We investigated progression through the care cascade and associated factors for people with diabetes in sub-Saharan Africa to identify attrition stages that may be most appropriate for targeted intervention., Design: Cross-sectional study., Setting: Community-based study in four sub-Saharan African countries., Participants: 10 700 individuals, aged 40-60 years., Primary and Secondary Outcome Measures: The primary outcome measure was the diabetes cascade of care defined as the age-adjusted diabetes prevalence (self-report of diabetes, fasting plasma glucose (FPG) ≥7 mmol/L or random plasma glucose ≥11.1 mmol/L) and proportions of those who reported awareness of having diabetes, ever having received treatment for diabetes and those who achieved glycaemic control (FPG <7.2 mmol/L). Secondary outcome measures were factors associated with having diabetes and being aware of the diagnosis., Results: Diabetes prevalence was 5.5% (95% CI 4.4% to 6.5%). Approximately half of those with diabetes were aware (54%; 95% CI 50% to 58%); 73% (95% CI 67% to 79%) of aware individuals reported ever having received treatment. However, only 38% (95% CI 30% to 46%) of those ever having received treatment were adequately controlled. Increasing age (OR 1.1; 95% CI 1.0 to 1.1), urban residence (OR 2.3; 95% CI 1.6 to 3.5), hypertension (OR 1.9; 95% CI 1.5 to 2.4), family history of diabetes (OR 3.9; 95% CI 3.0 to 5.1) and measures of central adiposity were associated with higher odds of having diabetes. Increasing age (OR 1.1; 95% CI 1.0 to 1.1), semi-rural residence (OR 2.5; 95% CI 1.1 to 5.7), secondary education (OR 2.4; 95% CI 1.2 to 4.9), hypertension (OR 1.6; 95% CI 1.0 to 2.4) and known HIV positivity (OR 2.3; 95% CI 1.2 to 4.4) were associated with greater likelihood of awareness of having diabetes., Conclusions: There is attrition at each stage of the diabetes care cascade in sub-Saharan Africa. Public health strategies should target improving diagnosis in high-risk individuals and intensifying therapy in individuals treated for diabetes., Competing Interests: Competing interests: ANW declares an honorarium received from Sanofi for serving as a panel member at an educational event on thyroid cancer. SAN declares participation in a data safety monitoring board of a Phase IV open-label trial to assess bone mineral density in a cohort of African women on Depo-Provera and tenofovir disoproxil fumarate switched to tenofovir alafenamide fumarate based antiretroviral therapy and Council membership in the International Society of Developmental Origins of Health and Disease., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2023
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31. Identifying the prevalence and correlates of multimorbidity in middle-aged men and women: a cross-sectional population-based study in four African countries.
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Micklesfield LK, Munthali R, Agongo G, Asiki G, Boua P, Choma SS, Crowther NJ, Fabian J, Gómez-Olivé FX, Kabudula C, Maimela E, Mohamed SF, Nonterah EA, Raal FJ, Sorgho H, Tluway FD, Wade AN, Norris SA, and Ramsay M
- Subjects
- Adult, Middle Aged, Male, Humans, Female, Multimorbidity, Risk Factors, Cross-Sectional Studies, Prevalence, Sex Factors, Africa South of the Sahara epidemiology, HIV Infections, Hypertension epidemiology, Dyslipidemias epidemiology
- Abstract
Objectives: To determine the prevalence of multimorbidity, to identify which chronic conditions cluster together and to identify factors associated with a greater risk for multimorbidity in sub-Saharan Africa (SSA)., Design: Cross-sectional, multicentre, population-based study., Setting: Six urban and rural communities in four sub-Saharan African countries., Participants: Men (n=4808) and women (n=5892) between the ages of 40 and 60 years from the AWI-Gen study., Measures: Sociodemographic and anthropometric data, and multimorbidity as defined by the presence of two or more of the following conditions: HIV infection, cardiovascular disease, chronic kidney disease, asthma, diabetes, dyslipidaemia, hypertension., Results: Multimorbidity prevalence was higher in women compared with men (47.2% vs 35%), and higher in South African men and women compared with their East and West African counterparts. The most common disease combination at all sites was dyslipidaemia and hypertension, with this combination being more prevalent in South African women than any single disease (25% vs 21.6%). Age and body mass index were associated with a higher risk of multimorbidity in men and women; however, lifestyle correlates such as smoking and physical activity were different between the sexes., Conclusions: The high prevalence of multimorbidity in middle-aged adults in SSA is of concern, with women currently at higher risk. This prevalence is expected to increase in men, as well as in the East and West African region with the ongoing epidemiological transition. Identifying common disease clusters and correlates of multimorbidity is critical to providing effective interventions., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY. Published by BMJ.)
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- 2023
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32. Physical Activity and Its Association With Body Mass Index: A Cross-Sectional Analysis in Middle-Aged Adults From 4 Sub-Saharan African Countries.
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Muti M, Ware LJ, Micklesfield LK, Ramsay M, Agongo G, Boua PR, Kisiangani I, Cook I, Gómez-Olivé FX, Crowther NJ, Kabudula C, Norris SA, and Chikowore T
- Subjects
- Middle Aged, Male, Adult, Humans, Female, Body Mass Index, Risk Factors, Cross-Sectional Studies, Africa South of the Sahara, Exercise, Obesity
- Abstract
Background: This study aimed to explore association of self-reported physical activity domains of work, leisure, and transport-related physical activity and body mass index (BMI) in 9388 adult men and women from the Africa-Wits-INDEPTH partnership for Genomic (AWI-Gen) study in Africa. Africa-Wits-INDEPTH partnership for Genomic is a large, population-based cross-sectional cohort with participants from 6 sites from rural and urban areas in 4 sub-Saharan African countries., Methods: A sex-stratified meta-analysis of cross-sectional data from men and women aged 29-82 years was used to assess the association of physical activity with BMI., Results: Overall, meeting physical activity guidelines of at least 150 minutes per week was associated with 0.82 kg/m2 lower BMI in men (β = -0.80 kg/m2; 95% confidence interval [CI], -1.14 to -0.47) and 0.68 kg/m2 lower BMI in women (β = -0.68 kg/m2; 95% CI, -1.03 to -0.33). Sex and site-specific differences were observed in the associations between physical activity domains and BMI. Among those who met physical activity guidelines, there was an inverse association between transport-related physical activity and BMI in men from Nanoro (Burkina Faso) (β = -0.79 kg/m2; 95% CI, -1.25 to -0.33) as well as work-related physical activity and BMI in Navrongo men (Ghana) (β = -0.76 kg/m2; 95% CI, -1.25 to -0.27) and Nanoro women (β = -0.90 kg/m2; 95% CI, -1.44 to -0.36)., Conclusions: Physical activity may be an effective strategy to curb rising obesity in Africa. More studies are needed to assess the impact of sex and geographic location-specific physical activity interventions on obesity.
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- 2023
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33. Estimating population level 24-h sodium excretion using spot urine samples in older adults in rural South Africa.
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Du Toit JD, Kapaon D, Crowther NJ, Abrahams-Gessel S, Fabian J, Kabudula CW, Wade AN, Tollman S, and Gaziano TA
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- Humans, Aged, South Africa, Sodium urine, Sodium Chloride, Dietary urine, Urine Specimen Collection methods, Potassium urine, Urinalysis methods, Sodium, Dietary
- Abstract
Background: South Africa has introduced regulations to reduce sodium in processed foods. Assessing salt consumption with 24-h urine collection is logistically challenging and expensive. We assess the accuracy of using spot urine samples to estimate 24-h urine sodium (24hrUNa) excretion at the population level in a cohort of older adults in rural South Africa., Methods: 24hrUNa excretion was measured and compared to that estimated from matched spot urine samples in 399 individuals, aged 40-75 years, from rural Mpumalanga, South Africa. We used the Tanaka, Kawasaki, International Study of Sodium, Potassium, and Blood Pressure (INTERSALT), and Population Mean Volume (PMV) method to predict 24hrUNa at the individual and population level., Results: The population median 24hrUNa excretion from our samples collected in 2017 was 2.6 g (interquartile range: 1.53-4.21) equal to an average daily salt intake of 6.6 g, whereas 65.4% of participants had a salt excretion above the WHO recommended 5 g/day. Estimated population median 24hrUNa derived from the INTERSALT, both with and without potassium, showed a nonsignificant difference of 0.25 g (P = 0.59) and 0.21 g (P = 0.67), respectively. In contrast, the Tanaka, Kawasaki, and PMV formulas were markedly higher than the measured 24hrUNa, with a median difference of 0.51 g (P = 0.004), 0.99 g (P = 0.00), and 1.05 g (P = 0.00) respectively. All formulas however performed poorly when predicting an individual's 24hrUNa., Conclusion: In this population, the INTERSALT formulas are a well suited and cost-effective alternative to 24-h urine collection for the evaluation of population median 24hrUNa excretion. This could play an important role for governments and public health agencies in evaluating local salt regulations and identifying at-risk populations., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)
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- 2023
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34. Targeted proteomics identifies potential biomarkers of dysglycaemia, beta cell function and insulin sensitivity in Black African men and women.
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Mendham AE, Micklesfield LK, Karpe F, Kengne AP, Chikowore T, Kufe CN, Masemola M, Crowther NJ, Norris SA, Olsson T, Elmståhl S, Fall T, Lind L, and Goedecke JH
- Subjects
- Female, Humans, Middle Aged, Proteomics, C-Peptide, Cross-Sectional Studies, South Africa, Insulin, Glucose, Insulin Resistance, Diabetes Mellitus, Type 2
- Abstract
Aims/hypothesis: Using a targeted proteomics approach, we aimed to identify and validate circulating proteins associated with impaired glucose metabolism (IGM) and type 2 diabetes in a Black South African cohort. In addition, we assessed sex-specific associations between the validated proteins and pathophysiological pathways of type 2 diabetes., Methods: This cross-sectional study included Black South African men (n=380) and women (n=375) who were part of the Middle-Aged Soweto Cohort (MASC). Dual-energy x-ray absorptiometry was used to determine fat mass and visceral adipose tissue, and fasting venous blood samples were collected for analysis of glucose, insulin and C-peptide and for targeted proteomics, measuring a total of 184 pre-selected protein biomarkers. An OGTT was performed on participants without diabetes, and peripheral insulin sensitivity (Matsuda index), HOMA-IR, basal insulin clearance, insulin secretion (C-peptide index) and beta cell function (disposition index) were estimated. Participants were classified as having normal glucose tolerance (NGT; n=546), IGM (n=116) or type 2 diabetes (n=93). Proteins associated with dysglycaemia (IGM or type 2 diabetes) in the MASC were validated in the Swedish EpiHealth cohort (NGT, n=1706; impaired fasting glucose, n=550; type 2 diabetes, n=210)., Results: We identified 73 proteins associated with dysglycaemia in the MASC, of which 34 were validated in the EpiHealth cohort. Among these validated proteins, 11 were associated with various measures of insulin dynamics, with the largest number of proteins being associated with HOMA-IR. In sex-specific analyses, IGF-binding protein 2 (IGFBP2) was associated with lower HOMA-IR in women (coefficient -0.35; 95% CI -0.44, -0.25) and men (coefficient -0.09; 95% CI -0.15, -0.03). Metalloproteinase inhibitor 4 (TIMP4) was associated with higher insulin secretion (coefficient 0.05; 95% CI 0.001, 0.11; p for interaction=0.025) and beta cell function (coefficient 0.06; 95% CI 0.02, 0.09; p for interaction=0.013) in women only. In contrast, a stronger positive association between IGFBP2 and insulin sensitivity determined using an OGTT (coefficient 0.38; 95% CI 0.27, 0.49) was observed in men (p for interaction=0.004). A posteriori analysis showed that the associations between TIMP4 and insulin dynamics were not mediated by adiposity. In contrast, most of the associations between IGFBP2 and insulin dynamics, except for insulin secretion, were mediated by either fat mass index or visceral adipose tissue in men and women. Fat mass index was the strongest mediator between IGFBP2 and insulin sensitivity (total effect mediated 40.7%; 95% CI 37.0, 43.6) and IGFBP2 and HOMA-IR (total effect mediated 39.1%; 95% CI 31.1, 43.5) in men., Conclusions/interpretation: We validated 34 proteins that were associated with type 2 diabetes, of which 11 were associated with measures of type 2 diabetes pathophysiology such as peripheral insulin sensitivity and beta cell function. This study highlights biomarkers that are similar between cohorts of different ancestry, with different lifestyles and sociodemographic profiles. The African-specific biomarkers identified require validation in African cohorts to identify risk markers and increase our understanding of the pathophysiology of type 2 diabetes in African populations., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
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- 2023
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35. Non-HDL-C and LDL-C/HDL-C are associated with self-reported cardiovascular disease in a rural West African population: Analysis of an array of lipid metrics in an AWI-Gen sub-study.
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Agongo G, Raal F, Nonterah EA, Debpuur C, Oduro AR, Ramsay M, and Crowther NJ
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- Humans, Female, Self Report, Cholesterol, LDL, Cross-Sectional Studies, Social Class, Cardiovascular Diseases epidemiology
- Abstract
Few studies have compared the utility of serum levels of lipid fractions in cardiovascular disease (CVD) risk assessment in sub-Saharan Africa (SSA). The current study interrogated this question among men and women aged 40-60 years in rural northern Ghana. This was a cross-sectional study in which data was collected on socio-demography, behaviour, health history, anthropometry and lipid levels. Adjusted multivariable logistic regression models were used to assess the association of various lipid metrics with CVD. All tests were considered statistically significant at P<0.05. Data were available for 1839 participants. The prevalence of self-reported CVD was 1.6% (n = 29). Non-HDL-C (median (interquartile range): 2.4 (1.9-3.0) vs 2.0 (1.6-2.5) mmol/L; P = 0.009), LDL-C/HDL-C (1.8 (1.4-2.4) vs 1.5 (1.1-2.6); P = 0.019) and TC/HDL-C (3.3 (2.9-3.9) vs 2.9 (2.4-3.5); P = 0.003) were all significantly higher in participants with self-reported CVD compared to those without. However, after adjusting for socioeconomic status (SES) and meals from vendors in a logistic regression model, only non-HDL-C (odds ratio [95% CIs]): (1.58 [1.05, 2.39]), P = 0.029 and LDL-C/HDL-C levels (odds ratio [95% CIs]): (1.26 [1.00, 1.59]), P = 0.045 remained significantly associated with self-reported CVD. While our findings suggest non-HDL-C and LDL-C/HDL-C measures may be appropriate biomarkers for assessing CVD risk in this population, further studies using established clinical endpoints are required to validate these findings in sub-Saharan Africans., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Agongo et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2022
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36. Differential glycosylation of tissue non-specific alkaline phosphatase in mesenchymal stromal cells differentiated into either an osteoblastic or adipocytic phenotype.
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Bartlett CL, Ralefatane MG, Cave EM, Crowther NJ, and Ferris WF
- Subjects
- Adipocytes metabolism, Glycosylation, Lipids, Neuraminidase metabolism, Perilipins metabolism, Phenotype, Wheat Germ Agglutinins metabolism, Cell Differentiation, Alkaline Phosphatase metabolism, Mesenchymal Stem Cells
- Abstract
It has long been known that tissue non-specific alkaline phosphatase (TNAP) is essential for the correct formation of bone, as altered expression or function of this enzyme results in hypophosphatasia, a disease characterised by compromised bone structure, density and strength. However, recent evidence strongly suggests that the enzyme also has a role in lipid accrual and adipogenesis, a function that seems far removed from bone formation. Given that mesenchymal stromal cells (MSCs) are progenitors of both osteoblasts and adipocytes, the question arises of how TNAP is regulated to potentially have a different function when MSCs undergo either osteogenesis or adipogenesis. As the primary protein sequence is unchanged for the enzyme during both types of differentiation, any differences in function must be attributed to post-translational modification and/or localisation. We therefore examined the location of TNAP in bone- or adipose-derived MSCs differentiated into an adipocytic phenotype and compared the glycosylation state of the enzyme in MSCs differentiated into either osteoblasts or adipocytes. TNAP was found to co-locate with perilipin around lipid droplets in MSCs from bone, subcutaneous- and visceral adipose tissue during adipocytic differentiation. Treatment of TNAP with wheat germ lectin followed by electrophoresis showed minor differences in glycosylation between the phosphatase isolated from cells from these tissues, whereas electrophoresis after neuraminidase digestion highlighted differential glycosylation between cell types and during adipogenesis and osteoblastogenesis. This infers that post-translational modification of TNAP is altered during differentiation and is dependent on the eventual phenotype of the cells., Competing Interests: Conflicts of interest There are no conflicts of interest., (Copyright © 2022 Elsevier Inc. All rights reserved.)
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- 2022
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37. Menopause is associated with bone loss, particularly at the distal radius, in black South African women: Findings from the Study of Women Entering and in Endocrine Transition (SWEET).
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Ó Breasail M, Gregson CL, Norris SA, Madanhire T, Jaff N, Crowther NJ, Micklesfield LK, and Ward KA
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- Absorptiometry, Photon, Bone Density, Female, Humans, Postmenopause, Radius, South Africa epidemiology, Tibia, Bone Diseases, Metabolic, HIV Infections epidemiology, Osteoporotic Fractures
- Abstract
Menopause transition is associated with accelerated bone loss, though data are limited from sub-Saharan African (SSA). Our objective was to describe bone density, geometry and estimated strength in women by menopause status and to explore whether patterns differed within those living with HIV., Methods: Radius and tibia peripheral QCT data were collected for Black South African women (n = 430) aged 40-61 years with verified menopause and HIV status. pQCT outcomes were distal 4 % radius and tibia total cross-sectional area (CSA), total volumetric bone mineral density (vBMD), and compressive bone strength (BSIc); proximal 66 % radius and 38 % tibia cortical vBMD, total CSA, cortical thickness, and Stress-strain Index (SSI). Linear regression assessed associations between pre, peri-, and postmenopausal groups and pQCT outcomes adjusting for age, height, and weight, and then stratified by HIV status. Mean [95%CI] and tests for trend (p-trend) across menopausal groups are presented., Results: Women were mean (SD) age 49.2 (5.3) years, with a body mass index (BMI) of 32.4 (6.3) m/kg
2 , and 18 % were living with HIV. After adjustment, later menopause stage was associated with lower 4 % radius total mean [95%CIs] vBMD (premenopause: 345.7 [335.8,355.5] vs. postmenopause: 330.1 [322.7,337.6] mg/cm3 , p-trend = 0.017) and BSIc (premenopause: 0.39 [0.37,0.41] vs. postmenopause: 0.36 [0.35,0.37] g2 /cm4 ; p-trend = 0.012). Similar trends were observed at the 66 % radius for cortical vBMD (premenopause: 1146.8 [1138.9,1154.6] vs. postmenopause: 1136.1 [1130.1,1142.0] mg/cm3 ; p-trend = 0.028) and cortical thickness (premenopause: 2.01 [1.95,2.06] vs. postmenopause: 1.93 [1.89,1.98] mm; p-trend = 0.036). After stratification by HIV status a similar patten was observed in women with HIV (cortical vBMD premenopause: 1152.9 [1128.5,1177.2] mg/cm3 vs. postmenopause: 1123.6 [1106.0,1141.2] mg/cm3 , p-trend = 0.048). Total CSA varied little by menopause or HIV status at either radius sites; few differences were found at the tibia., Conclusion: In black South African women, menopause is associated with lower bone density and strength at the distal radius, a common site of osteoporotic fracture, in addition to lower cortical density and thickness at the proximal radius. Although the sample size was small, following stratification by HIV, women living with HIV had evidence of lower cortical density across menopause stages, unlike those without HIV. These findings raise concern for the incidence of Colles' fractures in postmenopausal women in South Africa; longitudinal studies of fracture incidence and implications of living with HIV are required., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)- Published
- 2022
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38. The negative association of lower body fat mass with cardiometabolic disease risk factors is partially mediated by adiponectin.
- Author
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Gradidge PJ, Jaff NG, Norris SA, Toman M, and Crowther NJ
- Abstract
Gluteofemoral fat correlates negatively with a number of cardiometabolic disease risk factors, but the mechanisms involved in these relationships are unknown. The aim of this study was to test the hypothesis that gluteofemoral fat attenuates the risk of cardiometabolic disease by increasing blood adiponectin levels. This was a cross-sectional study in which arm, leg, gluteofemoral, abdominal s.c. and visceral fat levels were measured by dual-energy X-ray absorptiometry in 648 African females. Fasting serum adiponectin, lipid, insulin and plasma glucose levels and blood pressure were measured. Relationships between variables were analysed using multivariable linear regression and structural equation modelling. Adiponectin correlated positively (β = 0.45, P < 0.0001) with gluteofemoral fat in a multivariable regression model that included age, height, and arm, s.c. and visceral fat levels. In further regression models, there was a negative correlation of gluteofemoral fat with fasting glucose (β = -0.28; P < 0.0001) and triglyceride levels (β = -0.29; P < 0.0001) and insulin resistance (HOMA; β = -0.26; P < 0.0001). Structural equation modelling demonstrated that adiponectin mediated 20.7% (P < 0.01) of the association of gluteofemoral fat with insulin resistance and 16.1% (P < 0.01) of the association with triglyceride levels but only 6.67% (P = 0.31) of the association with glucose levels. These results demonstrate that gluteofemoral and leg fat are positively associated with adiponectin levels and that the negative association of lower body fat with insulin resistance and triglyceride levels may partially be mediated by this adipokine. Further studies are required to determine other factors that mediate the effect of lower body fat on cardiometabolic disease risk factors.
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- 2022
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39. Association of Longitudinal Nutrient Patterns with Body Composition in Black Middle-Aged South African Women: A Five-Year Follow-Up Study.
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Makura-Kankwende CBT, Gradidge PJ, Crowther NJ, Ratshikombo T, Goedecke JH, Micklesfield LK, Norris SA, and Chikowore T
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- Adiposity, Animals, Ascorbic Acid, Body Mass Index, Female, Follow-Up Studies, Potassium, South Africa, Sugars, Body Composition, Nutrients
- Abstract
This study aimed to evaluate the association of longitudinal nutrient patterns with body composition in a cohort of 132 black South African middle-aged women over five years. Nutrient patterns were identified using principal component analysis at baseline and follow-up 5 years later. Associations between nutrient patterns and repeated body composition measures were evaluated using generalized estimating equations, before and after adjusting for baseline education and repeated measures of age, socio-economic status, physical activity and employment. The animal-driven nutrient pattern was associated with increases in repeated measures of visceral adipose tissue (VAT) (β coefficient, 5.79 [95% CI, 0.01-11.57] cm
2 ), fat mass index (FMI) (0.47 [0.01-0.93] kg·m-2 ) and lean mass index (LMI) (0.50 [0.18-1.17] kg·m-2 ) ( p < 0.05) after adjustment. Vitamin C, sugar, and potassium-driven nutrient pattern was associated with higher FMI (0.50 [0.12-0.88] kg·m-2 ) and LMI (0.58 [0.07-1.10] kg·m-2 ) before and after adjustment ( p < 0.05). These findings suggest that dietary interventions to curb obesity in black middle-aged South African women should focus on attenuation of nutrient patterns centred on added sugar, animal fat and animal protein.- Published
- 2022
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40. The Effect of Obesity on the Waist Circumference Cut-Point Used for the Diagnosis of the Metabolic Syndrome in African Women: Results from the SWEET Study.
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Gradidge PJ, Norris SA, and Crowther NJ
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- Body Mass Index, Female, Humans, Obesity complications, Obesity epidemiology, ROC Curve, Risk Factors, Waist Circumference, Waist-Height Ratio, Waist-Hip Ratio, Metabolic Syndrome complications, Metabolic Syndrome diagnosis, Metabolic Syndrome epidemiology
- Abstract
Waist circumference (WC) is one of the diagnostic criteria for metabolic syndrome (MetS). However, studies have shown that the waist cut-point may be influenced by BMI. The aim of this study was to, therefore, determine whether the presence of obesity influences the WC cut-point used to diagnose MetS in sub-Saharan African women. The second aim was to determine whether calculated cut-points of other waist-related and dual-energy X-ray absorptiometry (DXA)-determined anthropometric measures used for the diagnosis of MetS were also influenced by BMI. Biochemical, simple anthropometric and dual-energy X-ray absorptiometry-derived anthropometric data were collected in 702 black South African women from the Study of Women Entering and in Endocrine Transition (SWEET). A receiver operating characteristic curve analysis was used to determine waist, waist-to-hip (WHR) and waist-to-height ratios, body shape index (ABSI), total body fat, trunk fat, and peripheral (arm + leg) fat cut-points for MetS (without waist) in subjects with BMI above or below the median value. The estimated WC cut-points (107 cm, 93.5 cm) for women with high BMI and low BMI, respectively, and the cut-points for the other anthropometric variables for the diagnosis of MetS were greater in high BMI women compared to low BMI women. The exceptions were WHR and ABSI, for which the cut-points were very similar in both BMI groups, and peripheral fat, where the cut-point was lower in the high BMI group. Logistic regression analysis demonstrated that WC was associated with a higher risk (odds ratio [95% CIs]: 1.07 [1.04, 1.10]; p < 0.0001), whilst hip was associated with a lower risk (0.97 [0.94, 0.99]; p = 0.02) for MetS. These data suggest that with increasing BMI, the higher levels of protective gluteofemoral fat lead to the requirement for higher WC cut-points for MetS diagnosis. The opposing associations of waist and hip with MetS risk make WHR a more appropriate variable for diagnosing MetS among African women as the WHR cut-point is less influenced by increasing BMI than is WC, which was also observed for ABSI.
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- 2022
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41. Author Correction: Meta-analysis of sub-Saharan African studies provides insights into genetic architecture of lipid traits.
- Author
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Choudhury A, Brandenburg JT, Chikowore T, Sengupta D, Boua PR, Crowther NJ, Agongo G, Asiki G, Gómez-Olivé FX, Kisiangani I, Maimela E, Masemola-Maphutha M, Micklesfield LK, Nonterah EA, Norris SA, Sorgho H, Tinto H, Tollman S, Graham SE, Willer CJ, Hazelhurst S, and Ramsay M
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- 2022
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42. Racial and Ethnic Differences in the Association Between Classical Cardiovascular Risk Factors and Common Carotid Intima-Media Thickness: An Individual Participant Data Meta-Analysis.
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Nonterah EA, Crowther NJ, Klipstein-Grobusch K, Oduro AR, Kavousi M, Agongo G, Anderson TJ, Asiki G, Boua PR, Choma SSR, Couper DJ, Engström G, de Graaf J, Kauhanen J, Lonn EM, Mathiesen EB, Micklesfield LK, Okazaki S, Polak JF, Rundek T, Salonen JT, Tollman SM, Tuomainen TP, Grobbee DE, Ramsay M, and Bots ML
- Subjects
- Carotid Intima-Media Thickness, Cross-Sectional Studies, Female, Heart Disease Risk Factors, Humans, Male, Risk Factors, Atherosclerosis, Cardiovascular Diseases diagnosis, Cardiovascular Diseases epidemiology
- Abstract
Background The major risk factors for atherosclerotic cardiovascular disease differ by race or ethnicity but have largely been defined using populations of European ancestry. Despite the rising prevalence of cardiovascular disease in Africa there are few related data from African populations. Therefore, we compared the association of established cardiovascular risk factors with carotid-intima media thickness (CIMT), a subclinical marker of atherosclerosis, between African, African American, Asian, European, and Hispanic populations. Methods and Results Cross-sectional analyses of 34 025 men and women drawn from 15 cohorts in Africa, Asia, Europe, and North America were undertaken. Classical cardiovascular risk factors were assessed and CIMT measured using B-mode ultrasound. Ethnic differences in the association of established cardiovascular risk factors with CIMT were determined using a 2-stage individual participant data meta-analysis with beta coefficients expressed as a percentage using the White population as the reference group. CIMT adjusted for risk factors was the greatest among African American populations followed by Asian, European, and Hispanic populations with African populations having the lowest mean CIMT. In all racial or ethnic groups, men had higher CIMT levels compared with women. Age, sex, body mass index, and systolic blood pressure had a significant positive association with CIMT in all races and ethnicities at varying magnitudes. When compared with European populations, the association of age, sex, and systolic blood pressure with CIMT was weaker in all races and ethnicities. Smoking (beta coefficient, 0.39; 95% CI, 0.09-0.70), body mass index (beta coefficient, 0.05; 95% CI, 0.01-0.08) and glucose (beta coefficient, 0.13; 95% CI, 0.06-0.19) had the strongest positive association with CIMT in the Asian population when compared with all other racial and ethnic groups. High-density lipoprotein-cholesterol had significant protective effects in African American (beta coefficient, -0.31; 95% CI, -0.42 to -0.21) and African (beta coefficient, -0.26; 95% CI, -0.31 to -0.19) populations only. Conclusions The strength of association between established cardiovascular risk factors and CIMT differed across the racial or ethnic groups and may be due to lifestyle risk factors and genetics. These differences have implications for race- ethnicity-specific primary prevention strategies and also give insights into the differential contribution of risk factors to the pathogenesis of cardiovascular disease. The greatest burden of subclinical atherosclerosis in African American individuals warrants further investigations.
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- 2022
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43. A new perspective on the function of Tissue Non-Specific Alkaline Phosphatase: from bone mineralization to intra-cellular lipid accumulation.
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Bartlett CL, Cave EM, Crowther NJ, and Ferris WF
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- Animals, Female, Humans, Isoenzymes, Lipids, Phosphates pharmacology, Placenta metabolism, Pregnancy, Alkaline Phosphatase metabolism, Calcification, Physiologic
- Abstract
Tissue-nonspecific alkaline phosphatase (TNAP) is one of four isozymes, which include germ cell, placental and intestinal alkaline phosphatases. The TNAP isozyme has 3 isoforms (liver, bone and kidney) which differ by tissue expression and glycosylation pattern. Despite a long history of investigation, the exact function of TNAP in many tissues is largely unknown. Only the bone isoform has been well characterised during mineralization where the enzyme hydrolyses pyrophosphate to inorganic phosphate, which combines with calcium to form hydroxyapatite crystals deposited as new bone. The inorganic phosphate also increases gene expression of proteins that support tissue mineralization. Recent studies have shown that TNAP is expressed in preadipocytes from several species, and that inhibition of TNAP activity causes attenuation of intracellular lipid accumulation in these and other lipid-storing cells. The mechanism by which TNAP stimulates lipid accumulation is not known; however, proteins that are important for controlling phosphate levels in bone are also expressed in adipocytes. This review examines the evidence that inorganic phosphate generated by TNAP promotes transcription that enhances the expression of the regulators of lipid storage and consequently, that TNAP has a major function of lipid metabolism., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2022
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44. The association of vitamin D binding protein levels and genotypes with type 1 diabetes in the black South African population.
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Cave EM, Bhola S, Crowther NJ, and Padoa CJ
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- Genotype, Humans, Polymorphism, Single Nucleotide, South Africa epidemiology, Vitamin D, Diabetes Mellitus, Type 1 epidemiology, Diabetes Mellitus, Type 1 genetics, Vitamin D-Binding Protein genetics
- Abstract
Background: Vitamin D deficiency and the vitamin D pathway have previously been associated with type 1 diabetes (T1D). The majority of vitamin D is transported through the blood bound to the vitamin D binding protein (VDBP). Two polymorphisms in the VDBP gene (rs4588 and rs7041) result in different VDBP variants and have been associated with T1D, however the results are not consistent. The association of VDBP levels and its polymorphisms with T1D have not been investigated in the black South African population. Therefore, this study aimed to determine whether rs4588, rs7041 or serum VDBP levels were associated with T1D in this population., Methods: Participants with type 1 diabetes and controls were recruited from the greater Johannesburg area, South Africa. Participants were genotyped for rs4588 and rs7041 using PCR-RFLP and serum VDBP levels were determined by ELISA., Results: There was no difference in VDBP allelic or genotypic frequencies between participants with T1D and controls (rs4588 C allele frequency 0.92 vs. 0.94; p = 0.390 and rs7041 T allele frequency 0.95 vs. 0.95; p = 0.890). In univariate analysis, the rs4588 CC genotype was associated with increased serum VDBP levels, however, this association was lost with multivariate analysis. The VDBP genotypes were not associated with any other study variables. In logistic regression analysis, higher VBDP levels were associated with T1D (OR: (95% CI): 6.58 (1.45-29.9); p = 0.015), and within a linear regression analysis, T1D disease status was found to be associated with 0.044 mg/ml higher VDBP levels (p = 0.028)., Conclusions: These data suggest that serum VDBP levels are positively associated with the presence of T1D in the African population. Whether VDBP lies in the causal pathway or its elevation is an effect of T1D is uncertain and requires further investigation., (© 2022. The Author(s).)
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- 2022
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45. Prevalence and Predictors of Abdominal Aorta Calcification in Patients With Psoriasis-A Case Control Study.
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Ramos S, Daya S, Crowther NJ, Pillay L, Tikly M, and Goolam Mahyoodeen N
- Abstract
Background: Psoriasis is associated with a high prevalence of cardiovascular disease in Caucasians, but only a few studies from sub-Saharan Africa have investigated the prevalence of cardiovascular disease in patients with psoriasis. Abdominal aortic calcification (AAC) is a strong predictor of future cardiovascular events and all-cause mortality in the general population. We investigated the prevalence and risk factors for AAC in a predominantly non-Caucasian cohort of South African patients with psoriasis., Methods: A cross-sectional case-control study of adult psoriasis patients ( n = 69) and controls ( n = 80), matched for gender, ethnicity and body mass index, attending tertiary Dermatology and Rheumatology clinics in Johannesburg, South Africa. Demographic, anthropometric, clinical and biochemical data were recorded. All participants underwent non-contrast abdominal CT scans. Images were assessed for AAC at the supra-coeliac aorta, supra-mesenteric aorta and aortic bifurcation using Horos DICOM viewer software., Results: Abdominal aortic calcification at any site was more prevalent in the psoriasis than control group (47.8% vs 22.5%, p < 0.005). The aortic bifurcation was the commonest site for AAC in both groups, but more prevalent in the psoriasis group (42.0% vs 21.3%, p < 0.005). The psoriasis group was also more likely to smoke, have hypertension and type 2 diabetes (56.5% vs 25.0%, p < 0.005; 72.0% vs 55.0%, p < 0.005; 24.6% vs 3.80%, p < 0.0005, respectively). Multivariable logistic regression analysis demonstrated that age, smoking and type 2 (T2DM) diabetes were independently associated with AAC (odds ratio (95% CIs): 1.16 (1.07, 1.20), 4.30 (2.15, 8.61) and 3.45 (1.09, 15.7) respectively), but psoriasis was not. Forward regression analysis demonstrated that smoking attenuated the association of psoriasis with AAC., Conclusion: Our findings show AAC to be more common in psoriasis patients compared to controls. Age, T2DM and smoking were independent predictors of AAC. Smoking cessation is essential in psoriatic patients to reduce the risk of cardiovascular events. The clinical utility of AAC detection by CT imaging to risk stratify for hard cardiovascular outcomes needs to be explored., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Ramos, Daya, Crowther, Pillay, Tikly and Goolam Mahyoodeen.)
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- 2022
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46. Meta-analysis of sub-Saharan African studies provides insights into genetic architecture of lipid traits.
- Author
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Choudhury A, Brandenburg JT, Chikowore T, Sengupta D, Boua PR, Crowther NJ, Agongo G, Asiki G, Gómez-Olivé FX, Kisiangani I, Maimela E, Masemola-Maphutha M, Micklesfield LK, Nonterah EA, Norris SA, Sorgho H, Tinto H, Tollman S, Graham SE, Willer CJ, Hazelhurst S, and Ramsay M
- Subjects
- Africa South of the Sahara, Cholesterol, LDL genetics, Cross-Sectional Studies, Humans, Genome-Wide Association Study
- Abstract
Genetic associations for lipid traits have identified hundreds of variants with clear differences across European, Asian and African studies. Based on a sub-Saharan-African GWAS for lipid traits in the population cross-sectional AWI-Gen cohort (N = 10,603) we report a novel LDL-C association in the GATB region (P-value=1.56 × 10
-8 ). Meta-analysis with four other African cohorts (N = 23,718) provides supporting evidence for the LDL-C association with the GATB/FHIP1A region and identifies a novel triglyceride association signal close to the FHIT gene (P-value =2.66 × 10-8 ). Our data enable fine-mapping of several well-known lipid-trait loci including LDLR, PMFBP1 and LPA. The transferability of signals detected in two large global studies (GLGC and PAGE) consistently improves with an increase in the size of the African replication cohort. Polygenic risk score analysis shows increased predictive accuracy for LDL-C levels with the narrowing of genetic distance between the discovery dataset and our cohort. Novel discovery is enhanced with the inclusion of African data., (© 2022. The Author(s).)- Published
- 2022
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47. Waist circumference thresholds predicting incident dysglycaemia and type 2 diabetes in Black African men and women.
- Author
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Goedecke JH, Nguyen KA, Kufe C, Masemola M, Chikowore T, Mendham AE, Norris SA, Crowther NJ, Karpe F, Olsson T, Kengne AP, and Micklesfield LK
- Subjects
- Body Mass Index, Cohort Studies, Female, Humans, Male, Middle Aged, Prospective Studies, Risk Factors, Waist Circumference physiology, Diabetes Mellitus, Type 2 diagnosis, Diabetes Mellitus, Type 2 epidemiology, Metabolic Syndrome epidemiology
- Abstract
Aims: To determine the waist circumference (WC) thresholds for the prediction of incident dysglycaemia and type 2 diabetes (T2D) in Black South African (SA) men and women and to compare these to the advocated International Diabetes Federation (IDF) Europid thresholds., Materials and Methods: In this prospective study, Black SA men (n = 502) and women (n = 527) from the Middle-aged Sowetan Cohort study who had normal or impaired fasting glucose at baseline (2011-2015) were followed up until 2017 to 2018. Baseline measurements included anthropometry, blood pressure and fasting glucose, HDL cholesterol and triglyceride concentrations. At follow-up, glucose tolerance was assessed using an oral glucose tolerance test. The Youden index was used to determine the optimal threshold of WC to predict incident dysglycaemia and T2D., Results: In men, the optimal WC threshold was 96.8 cm for both dysglycaemia and T2D (sensitivity: 56% and 70%; specificity: 74% and 70%, respectively), and had higher specificity (P < 0.001) than the IDF threshold of 94 cm. In women, the optimal WC threshold for incident dysglycaemia was 91.8 cm (sensitivity 86%, specificity 37%) and for T2D it was 95.8 cm (sensitivity 85%, specificity 45%), which had lower sensitivity, but higher specificity to predict incident dysglycaemia and T2D than the IDF threshold of 80 cm (sensitivity: 97% and 100%; specificity: 12% and 11%, respectively))., Conclusions: We show for the first time using prospective cohort data from Africa that the IDF Europid WC thresholds are not appropriate for an African population, and show that African-specific WC thresholds perform better than the IDF Europid thresholds to predict incident dysglycaemia and T2D., (© 2022 The Authors. Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.)
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- 2022
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48. Carotid Atherosclerosis, Microalbuminuria, and Estimated 10-Year Atherosclerotic Cardiovascular Disease Risk in Sub-Saharan Africa.
- Author
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Nonterah EA, Boateng D, Crowther NJ, Klipstein-Grobusch K, Oduro AR, Agongo G, Mohamed SF, Boua PR, Choma SSR, Norris SA, Tollman SM, Bots ML, Ramsay M, and Grobbee D
- Subjects
- Albumins, Albuminuria epidemiology, Carotid Intima-Media Thickness, Cross-Sectional Studies, Female, Ghana, Humans, Male, Middle Aged, Atherosclerosis epidemiology, Cardiovascular Diseases epidemiology, Carotid Artery Diseases diagnostic imaging, Carotid Artery Diseases epidemiology, Hypertension epidemiology
- Abstract
Importance: Carotid atherosclerosis and microalbuminuria are associated with atherosclerotic cardiovascular disease (ASCVD) but are understudied in sub-Saharan Africa., Objective: To evaluate the association of carotid atherosclerosis and microalbuminuria with 10-year ASCVD risk in middle-aged sub-Saharan African individuals., Design, Setting, and Participants: This cross-sectional study conducted analyses of baseline data from the African-Wits-INDEPTH (International Network for the Demographic Evaluation of Populations and Their Health in Low- and Middle-Income Countries) genomic study (AWI-Gen). Women and men aged 40 to 60 years without baseline CVD and drawn from Burkina Faso, Ghana, Kenya, and South Africa were included., Main Outcomes and Measures: Hypotheses for the analyses were formulated after data collection. The main exposures were carotid atherosclerosis, assessed using carotid intima-media thickness (CIMT) using B-mode ultrasonography, and microalbuminuria, measured using spot urine albumin (SUA) and urine albumin-creatinine ratio (uACR). The main outcome was high ASCVD risk, defined as a 2018 Pooled Cohort Equations score of 7.5% or greater. Associations were estimated using adjusted multivariable logistic regression analyses., Findings: A total of 9010 participants with a mean (SD) age of 50 (6) years and 4533 (50.3%) women were included. High CIMT, SUA, and uACR were each associated with older age (eg, mean [SD] age of participants with high vs reference range CIMT: 55 [5] years vs 50 [6] years; P < .001) and high prevalence of both diabetes and hypertension (eg, hypertension among those with high vs reference range SUA: 213 of 1117 [19.1%] vs 356 of 2549 [14.0%]; P < .001). Smokers were likely to have higher vs reference range SUA (210 [18.8%] vs 407 [16.0%]) and uACR (138 of 707 [19.5%] vs 456 of 2797 [16.3%]). Carotid atherosclerosis was common in Burkina Faso (82 of 262 [31.3%]) and Ghana (91 [34.7%]), while microalbuminuria, measured by SUA, was common in Kenya (272 [24.4%]) and South Africa (519 [46.5%]). SUA was associated with higher odds of carotid atherosclerosis (odds ratio [OR], 1.77; 95% CI, 1.04-3.01) compared with uACR (OR, 0.51; 95% CI, 0.27-0.95). Common CIMT, SUA, and uACR were associated with 10-year ASCVD risk, with CIMT having a stronger association with 10-year ASCVD risk in both women (OR, 1.95; 95% CI, 1.78-2.14) and men (OR, 1.73; 95% CI, 1.55-1.93) than SUA (women: OR, 1.29; 95% CI, 1.12-1.43; men: OR, 1.46; 95% CI, 1.26-1.55) and uACR (women: OR, 1.32; 95% CI, 1.10-1.54; men: OR, 1.35; 95% CI, 1.15-1.46)., Conclusions and Relevance: The presence of microalbuminuria measured by SUA may indicate risk of subclinical carotid atherosclerosis and high 10-year ASCVD risk in middle-aged residents of sub-Saharan Africa. These data should be confirmed in longitudinal studies of cardiovascular events.
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- 2022
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49. Increased risk for type 2 diabetes in relation to adiposity in middle-aged Black South African men compared to women.
- Author
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Kufe CN, Micklesfield LK, Masemola M, Chikowore T, Kengne AP, Karpe F, Norris SA, Crowther NJ, Olsson T, and Goedecke JH
- Subjects
- Adiposity, Body Mass Index, Cross-Sectional Studies, Female, Humans, Male, Middle Aged, Obesity epidemiology, South Africa epidemiology, Diabetes Mellitus, Type 2 epidemiology, Insulin Resistance
- Abstract
Aims: Despite a higher prevalence of overweight/obesity in Black South African women compared to men, the prevalence of type 2 diabetes (T2D) does not differ. We explored if this could be due to sex differences in insulin sensitivity, clearance and/or beta-cell function and also sex-specific associations with total and regional adiposity., Methods: This cross-sectional study included 804 Black South African men (n = 388) and women (n = 416). Dual-energy X-ray absorptiometry was used to measure total and regional adiposity. Insulin sensitivity (Matsuda index), secretion (C-peptide index) and clearance (C-peptide/insulin ratio) were estimated from an oral glucose tolerance test., Results: After adjusting for sex differences in the fat mass index, men were less insulin sensitive and had lower beta-cell function than women (P < 0.001), with the strength of the associations with measures of total and central adiposity being greater in men than women (P < 0.001 for interactions). Further, the association between total adiposity and T2D risk was also greater in men than women (relative risk ratio (95% CI): 2.05 (1.42-2.96), P < 0.001 vs 1.38 (1.03-1.85), P = 0.031)., Conclusion: With increasing adiposity, particularly increased centralisation of body fat linked to decreased insulin sensitivity and beta-cell function, Black African men are at greater risk for T2D than their female counterparts.
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- 2022
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50. Genetic associations with carotid intima-media thickness link to atherosclerosis with sex-specific effects in sub-Saharan Africans.
- Author
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Boua PR, Brandenburg JT, Choudhury A, Sorgho H, Nonterah EA, Agongo G, Asiki G, Micklesfield L, Choma S, Gómez-Olivé FX, Hazelhurst S, Tinto H, Crowther NJ, Mathew CG, and Ramsay M
- Subjects
- Adult, Africa South of the Sahara, Autoantigens genetics, Cardiovascular Diseases genetics, Female, Gastrointestinal Hormones genetics, Genome genetics, Histones genetics, Humans, Male, Middle Aged, Polymorphism, Single Nucleotide genetics, Ribonucleoproteins genetics, Sex Factors, Sorting Nexins genetics, Vascular Endothelial Growth Factor, Endocrine-Gland-Derived genetics, SS-B Antigen, Atherosclerosis genetics, Atherosclerosis pathology, Carotid Intima-Media Thickness statistics & numerical data, Genetic Predisposition to Disease genetics
- Abstract
Atherosclerosis precedes the onset of clinical manifestations of cardiovascular diseases (CVDs). We used carotid intima-media thickness (cIMT) to investigate genetic susceptibility to atherosclerosis in 7894 unrelated adults (3963 women, 3931 men; 40 to 60 years) resident in four sub-Saharan African countries. cIMT was measured by ultrasound and genotyping was performed on the H3Africa SNP Array. Two new African-specific genome-wide significant loci for mean-max cIMT, SIRPA (p = 4.7E-08), and FBXL17 (p = 2.5E-08), were identified. Sex-stratified analysis revealed associations with one male-specific locus, SNX29 (p = 6.3E-09), and two female-specific loci, LARP6 (p = 2.4E-09) and PROK1 (p = 1.0E-08). We replicate previous cIMT associations with different lead SNPs in linkage disequilibrium with SNPs primarily identified in European populations. Our study find significant enrichment for genes involved in oestrogen response from female-specific signals. The genes identified show biological relevance to atherosclerosis and/or CVDs, sex-differences and transferability of signals from non-African studies., (© 2022. The Author(s).)
- Published
- 2022
- Full Text
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