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It has been shown using proton magnetic resonance spectroscopy ( 1 H MRS) that, in a group of females, whole-body insulin resistance was more closely related to accumulation of saturated intramyocellular lipid (IMCL) than to IMCL concentration alone. This has not been investigated in males. We investigated whether age- and body mass index-matched healthy males differ from the previously reported females in IMCL composition (measured as CH 2 :CH 3 ) and IMCL concentration (measured as CH 3 ), and in their associations with insulin resistance. We ask whether saturated IMCL accumulation is more strongly associated with insulin resistance than other ectopic and adipose tissue lipid pools and remains a significant predictor when these other pools are taken into account. In this group of males, who had similar overall insulin sensitivity to the females, IMCL was similar between sexes. The males demonstrated similar and even stronger associations of IMCL with insulin resistance, supporting the idea that a marker reflecting the accumulation of saturated IMCL is more strongly associated with whole-body insulin resistance than IMCL concentration alone. However, this marker ceased to be a significant predictor of whole-body insulin resistance after consideration of other lipid pools, which implies that this measure carries no more information in practice than the other predictors we found, such as intrahepatic lipid and visceral adipose tissue. As the marker of saturated IMCL accumulation appears to be related to these two predictors and has a much smaller dynamic range, this finding does not rule out a role for it in the pathogenesis of insulin resistance., (© 2024 The Authors. NMR in Biomedicine published by John Wiley & Sons Ltd.)

Background and Aim: Fatty Liver Index (FLI) is a simple clinical scoring system estimating non-alcoholic fatty liver disease (NAFLD). It is validated in European-descent and Asian populations, but not in sub-Saharan Africans. The aim of this study is to evaluate the validity of the FLI for predicting NAFLD in a population from Kenya., Methods: Participants were recruited from a community-based study conducted in Kenya. NAFLD was diagnosed using hepatic ultrasonography. Clinical, anthropometrical, biochemical and lifestyle data were obtained. The accuracy and cut-off point of the FLI to detect NAFLD were evaluated by area under the receiver operator characteristic curve and the maximum Youden index analysis., Results: A total of 640 participants (94 with NAFLD) were included. Mean age was 37.4 ± 0.4 years and 58.7% were women. Mean body mass index (BMI) was 22.3 ± 0.2 kg/m 2 and waist circumference (WC) 79.1 ± 0.4 cm. A total of 15 (2.3%) participants were diagnosed with type 2 diabetes and 65 (10.2%) with obesity (BMI ≥ 30 kg/m 2 ). AUROC of FLI for predicting NAFLD was 0.80 (95% CI 0.74-0.85), which was significantly higher compared to individual components gamma-glutamyl transferase and triglycerides (p < 0.05), but not compared to anthropometric parameters BMI (AUROC of 0.83, 95% CI 0.79-0.88) and WC (AUROC of 0.81, 95% CI 0.76-0.87)., Conclusions: FLI is a simple valid scoring system to use in rural and urban Kenyan adults. However, this index might not be superior to BMI or WC to predict NAFLD, and those measurements might therefore be more appropriate in limited settings., (© 2023 The Authors Tropical Medicine & International Health Published by John Wiley & Sons Ltd.)

Background: Early epidemiological studies have associated low birthweight with increased cardiovascular risk. We aimed to examine whether the fat and fat-free components of birthweight have differing relationships with childhood cardiovascular risk markers., Methods: In the Growing Up in Singapore Towards healthy Outcomes (GUSTO) cohort, air displacement plethysmography was conducted within 24 h after delivery in 290 naturally conceived singletons. We investigated associations of newborn cohort-specific standardized z-score of fat mass, fat-free mass, body fat percentage and birthweight on child (at 6 years of age) carotid intima-media thickness, pulse wave velocity, blood pressure, prehypertension/hypertension (>110/70 mmHg) and standardized systolic and diastolic blood pressure (SBP and DBP) trajectories (at 3-6 years of age), taking account of maternal education, height, tobacco exposure, parity, ethnicity, child's sex, gestational age, age at follow-up, and other maternal factors., Results: Clear inverse associations were seen for blood pressure with z-score of fat mass [SBP, β (95% CI): -1.31 mmHg (-2.57, -0.06); DBP: -0.79 mmHg (-1.74, 0.15)] and body fat percentage [SBP: -1.46 mmHg (-2.73, -0.19); DBP: -0.80 mmHg (-1.75, 0.16)], but not with fat-free mass [SBP: 0.27 mmHg (-1.29, 1.83)]; DBP: -0.14 mmHg (-1.30, 1.03)]. Being in the lowest tertile of fat mass or body fat percentage was associated with higher blood pressure trajectories and prehypertension/hypertension risk [OR (95% CI), fat mass: 4.23 (1.41, 12.68); body fat percentage: 3.22 (1.09, 9.53)] without concomitantly higher overweight/obesity risk., Conclusions: At birth, low adiposity was associated with increased childhood blood pressure. Low newborn adiposity might serve as a marker of poor fetal growth or suboptimal intrauterine conditions associated with hypertension risk later in life., (© The Author(s) 2022; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.)

Background/objectives: Physical activity energy expenditure (PAEE) represents the total volume of all physical activity. This can be accumulated as different underlying intensity profiles. Although volume and intensity have been studied in isolation, less is known about their joint association with health. We examined this association with body fatness in a population-based sample of middle-aged British adults., Methods: In total, 6148 women and 5320 men from the Fenland study with objectively measured physical activity from individually calibrated combined heart rate and movement sensing and DXA-derived body fat percentage (BF%) were included in the analyses. We used linear and compositional isocaloric substitution analysis to examine associations of PAEE and its intensity composition with body fatness. Sex-stratified models were adjusted for socio-economic and dietary covariates., Results: PAEE was inversely associated with body fatness in women (beta = -0.16 (95% CI: -0.17; -0.15) BF% per kJ day -1  kg -1 ) and men (beta = -0.09 (95% CI: -0.10; -0.08) BF% per kJ day -1  kg -1 ). Intensity composition was significantly associated with body fatness, beyond that of PAEE; the reallocation of energy to vigorous physical activity (>6 METs) from other intensities was associated with less body fatness, whereas light activity (1.5-3 METs) was positively associated. However, light activity was the main driver of overall PAEE volume, and the relative importance of intensity was marginal compared to that of volume; the difference between PAEE in tertile 1 and 2 in women was associated with 3 percentage-point lower BF%. Higher vigorous physical activity in the same group to the maximum observed value was associated with 1 percentage-point lower BF%., Conclusions: In this large, population-based cohort study with objective measures, PAEE was inversely associated with body fatness. Beyond the PAEE association, greater levels of intense activity were also associated with lower body fatness. This contribution was marginal relative to PAEE. These findings support current guidelines for physical activity which emphasise that any movement is beneficial, rather than specific activity intensity or duration targets., (© 2021. The Author(s).)

Objective: We aimed to determine the associations of non-alcoholic fatty liver disease (NAFLD) with cardio-metabolic risk factors for diabetes in adult Kenyans., Methods: A cross-sectional study was undertaken among rural and urban Kenyans of different ethnic origin. Ultrasonography scanning (USS) methods were used for the assessment of hepatic fat accumulation for NAFLD assessment and abdominal fat distribution, and simple anthropometry measurements were performed. All participants underwent a 2-h oral glucose tolerance test, and biochemical, haemodynamic and lifestyle data were obtained. Multivariate logistic regression analyses were used to assess sex, age, residency and ethnic differences in the association between NAFLD and various metabolic parameters., Results: In total, 743 individuals (59.1% women) with a mean age of 38.0 (range 18-68) years participated in the study. Overall, 118 individuals (15.9%) had NAFLD, of whom 94.1% had mild steatosis. Age >40 years was significantly associated with having NAFLD compared with <30 years of age with no difference found in NAFLD between ethnic groups (Luo, Kamba, Maasai). All body composition and clinical measurements were associated with NAFLD (p < 0.045 for OR)., Conclusion: Finding lower odds for NAFLD in men was unexpected, as was the lack of differences in NAFLD among the ethnic groups, while higher odds for NAFLD with increasing age and in urban vs. rural populations was expected. Especially the sex-specific results warrant further studies in black African populations on biology of body composition for having NAFLD, and whether this translates into insulin resistance and higher risk of diabetes and consequently cardiovascular disease in black African women., (© 2021 John Wiley & Sons Ltd.)