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Background: We previously developed an African-ancestry-specific polygenic hazard score (PHS46+African) that substantially improved prostate cancer risk stratification in men with African ancestry. The model consists of 46 SNPs identified in Europeans and 3 SNPs from 8q24 shown to improve model performance in Africans. Herein, we used principal component (PC) analysis to uncover subpopulations of men with African ancestry for whom the utility of PHS46+African may differ., Materials and Methods: Genotypic data were obtained from the PRACTICAL consortium for 6253 men with African genetic ancestry. Genetic variation in a window spanning 3 African-specific 8q24 SNPs was estimated using 93 PCs. A Cox proportional hazards framework was used to identify the pair of PCs most strongly associated with the performance of PHS46+African. A calibration factor (CF) was formulated using Cox coefficients to quantify the extent to which the performance of PHS46+African varies with PC., Results: CF of PHS46+African was strongly associated with the first and twentieth PCs. Predicted CF ranged from 0.41 to 2.94, suggesting that PHS46+African may be up to 7 times more beneficial to some African men than others. The explained relative risk for PHS46+African varied from 3.6% to 9.9% for individuals with low and high CF values, respectively. By cross-referencing our data set with 1000 Genomes, we identified significant associations between continental and calibration groupings., Conclusion: We identified PCs within 8q24 that were strongly associated with the performance of PHS46+African. Further research to improve the clinical utility of polygenic risk scores (or models) is needed to improve health outcomes for men of African ancestry., (© 2021. The Author(s), under exclusive licence to Springer Nature Limited.)

Although many loci have been associated with height in European ancestry populations, very few have been identified in African ancestry individuals. Furthermore, many of the known loci have yet to be generalized to and fine-mapped within a large-scale African ancestry sample. We performed sex-combined and sex-stratified meta-analyses in up to 52,764 individuals with height and genome-wide genotyping data from the African Ancestry Anthropometry Genetics Consortium (AAAGC). We additionally combined our African ancestry meta-analysis results with published European genome-wide association study (GWAS) data. In the African ancestry analyses, we identified three novel loci (SLC4A3, NCOA2, ECD/FAM149B1) in sex-combined results and two loci (CRB1, KLF6) in women only. In the African plus European sex-combined GWAS, we identified an additional three novel loci (RCCD1, G6PC3, CEP95) which were equally driven by AAAGC and European results. Among 39 genome-wide significant signals at known loci, conditioning index SNPs from European studies identified 20 secondary signals. Two of the 20 new secondary signals and none of the 8 novel loci had minor allele frequencies (MAF) < 5%. Of 802 known European height signals, 643 displayed directionally consistent associations with height, of which 205 were nominally significant (p < 0.05) in the African ancestry sex-combined sample. Furthermore, 148 of 241 loci contained ≤20 variants in the credible sets that jointly account for 99% of the posterior probability of driving the associations. In summary, trans-ethnic meta-analyses revealed novel signals and further improved fine-mapping of putative causal variants in loci shared between African and European ancestry populations., (Copyright © 2021 American Society of Human Genetics. All rights reserved.)

Polygenic hazard score (PHS) models are associated with age at diagnosis of prostate cancer. Our model developed in Europeans (PHS46) showed reduced performance in men with African genetic ancestry. We used a cross-validated search to identify single nucleotide polymorphisms (SNPs) that might improve performance in this population. Anonymized genotypic data were obtained from the PRACTICAL consortium for 6253 men with African genetic ancestry. Ten iterations of a 10-fold cross-validation search were conducted to select SNPs that would be included in the final PHS46+African model. The coefficients of PHS46+African were estimated in a Cox proportional hazards framework using age at diagnosis as the dependent variable and PHS46, and selected SNPs as predictors. The performance of PHS46 and PHS46+African was compared using the same cross-validated approach. Three SNPs (rs76229939, rs74421890 and rs5013678) were selected for inclusion in PHS46+African. All three SNPs are located on chromosome 8q24. PHS46+African showed substantial improvements in all performance metrics measured, including a 75% increase in the relative hazard of those in the upper 20% compared to the bottom 20% (2.47-4.34) and a 20% reduction in the relative hazard of those in the bottom 20% compared to the middle 40% (0.65-0.53). In conclusion, we identified three SNPs that substantially improved the association of PHS46 with age at diagnosis of prostate cancer in men with African genetic ancestry to levels comparable to Europeans., (© 2020 Union for International Cancer Control.)

Introduction: The Southern Community Cohort Study is a prospective study of low socioeconomic status (SES) blacks and whites from the southeastern US, where the burden of end-stage renal disease (ESRD) and its risk factors are high. We tested whether the 2.4-fold elevated risk of ESRD we previously observed in blacks compared to whites was explained by differences in baseline kidney function., Methods: We conducted a case-cohort study of incident ESRD cases (n = 737) with stored blood and a probability sampled subcohort (n = 4238) and calculated estimated glomerular filtration rate (eGFR) from serum creatinine. 86% of participants were enrolled from community health centers in medically underserved areas and 14% from the general population in 12 states in the southeastern United States. Incident ESRD after entry into the cohort was ascertained by linkage of the cohort with the US Renal Data System (USRDS)., Results: Median (25th, 75th percentile) eGFR at baseline was 63.3 (36.0, 98.2) ml/min/1.73m 2 for ESRD cases and 103.2 (86.0, 117.9) for subcohort. Black ESRD cases had higher median (25th, 75th) eGFR [63.3 (35.9, 95.9)] compared to whites [59.1 (39.4, 99.2)]. In multivariable Cox models accounting for sampling weights, baseline eGFR was a strong predictor of ESRD risk, and an interaction with race was detected (P = 0.029). The higher ESRD risk among blacks relative to whites persisted (hazard ratio: 2.58; 95% confidence interval: 1.65, 4.03) after adjustment for eGFR., Conclusion: In this predominantly lower SES cohort, the racial disparity in ESRD risk is not explained by differences in baseline kidney function.

Prostate cancer incidence is 1.6-fold higher in African Americans than in other populations. The risk factors that drive this disparity are unknown and potentially consist of social, environmental, and genetic influences. To investigate the genetic basis of prostate cancer in men of African ancestry, we performed a genome-wide association meta-analysis using two-sided statistical tests in 10 202 case subjects and 10 810 control subjects. We identified novel signals on chromosomes 13q34 and 22q12, with the risk-associated alleles found only in men of African ancestry (13q34: rs75823044, risk allele frequency = 2.2%, odds ratio [OR] = 1.55, 95% confidence interval [CI] = 1.37 to 1.76, P = 6.10 × 10-12; 22q12.1: rs78554043, risk allele frequency = 1.5%, OR = 1.62, 95% CI = 1.39 to 1.89, P = 7.50 × 10-10). At 13q34, the signal is located 5' of the gene IRS2 and 3' of a long noncoding RNA, while at 22q12 the candidate functional allele is a missense variant in the CHEK2 gene. These findings provide further support for the role of ancestry-specific germline variation in contributing to population differences in prostate cancer risk., (© The Author 2017. Published by Oxford University Press.)

Background: Genome-wide association studies (GWAS) in European populations have identified genetic risk variants associated with multiple myeloma., Methods: We performed association testing of common variation in eight regions in 1,318 patients with multiple myeloma and 1,480 controls of European ancestry and 1,305 patients with multiple myeloma and 7,078 controls of African ancestry and conducted a meta-analysis to localize the signals, with epigenetic annotation used to predict functionality., Results: We found that variants in 7p15.3, 17p11.2, 22q13.1 were statistically significantly (P < 0.05) associated with multiple myeloma risk in persons of African ancestry and persons of European ancestry, and the variant in 3p22.1 was associated in European ancestry only. In a combined African ancestry-European ancestry meta-analysis, variation in five regions (2p23.3, 3p22.1, 7p15.3, 17p11.2, 22q13.1) was statistically significantly associated with multiple myeloma risk. In 3p22.1, the correlated variants clustered within the gene body of ULK4 Correlated variants in 7p15.3 clustered around an enhancer at the 3' end of the CDCA7L transcription termination site. A missense variant at 17p11.2 (rs34562254, Pro251Leu, OR, 1.32; P = 2.93 × 10 -7 ) in TNFRSF13B encodes a lymphocyte-specific protein in the TNF receptor family that interacts with the NF-κB pathway. SNPs correlated with the index signal in 22q13.1 cluster around the promoter and enhancer regions of CBX7 CONCLUSIONS: We found that reported multiple myeloma susceptibility regions contain risk variants important across populations, supporting the use of multiple racial/ethnic groups with different underlying genetic architecture to enhance the localization and identification of putatively functional alleles., Impact: A subset of reported risk loci for multiple myeloma has consistent effects across populations and is likely to be functional. Cancer Epidemiol Biomarkers Prev; 25(12); 1609-18. ©2016 AACR., (©2016 American Association for Cancer Research.)

Background: In contrast to whites, black smokers prefer menthol cigarettes over nonmenthol cigarettes by a large margin and tend to have higher mortality from several smoking-related diseases than whites, raising the possibility that menthol cigarettes contribute to racial disparities in risk. Evidence for differential associations between menthol and nonmenthol cigarettes indicates lower cancer risk for menthol smokers, but for cardiovascular disease (CVD) mortality, evidence has been inconsistent., Methods and Results: Cox proportional hazards models were used to compute hazard ratios and accompanying 95% confidence intervals for all-cause and CVD mortality for menthol compared with nonmenthol cigarette smokers among 65 600 participants in the Southern Community Cohort Study, an ongoing community-based cohort with the largest number of menthol smokers being traced. Among the 27 619 current cigarette smokers, 4224 died during follow-up, with 1130 deaths attributed to CVD. Both all-cause (hazard ratio=0.93; 95% confidence interval=0.86-1.01; P=0.10) and CVD (hazard ratio=0.88; 95% confidence interval=0.76-1.03; P=0.10) mortality risks were similar in menthol compared with nonmenthol cigarette smokers., Conclusions: Smoking regardless of cigarette type is hazardous to health, but these results do not indicate that menthol cigarettes are associated with greater CVD risks than nonmenthol cigarettes., (© 2016 American Heart Association, Inc.)

Interpretation of biological mechanisms underlying genetic risk associations for prostate cancer is complicated by the relatively large number of risk variants (n = 100) and the thousands of surrogate SNPs in linkage disequilibrium. Here, we combined three distinct approaches: multiethnic fine-mapping, putative functional annotation (based upon epigenetic data and genome-encoded features), and expression quantitative trait loci (eQTL) analyses, in an attempt to reduce this complexity. We examined 67 risk regions using genotyping and imputation-based fine-mapping in populations of European (cases/controls: 8600/6946), African (cases/controls: 5327/5136), Japanese (cases/controls: 2563/4391) and Latino (cases/controls: 1034/1046) ancestry. Markers at 55 regions passed a region-specific significance threshold (P-value cutoff range: 3.9 × 10(-4)-5.6 × 10(-3)) and in 30 regions we identified markers that were more significantly associated with risk than the previously reported variants in the multiethnic sample. Novel secondary signals (P < 5.0 × 10(-6)) were also detected in two regions (rs13062436/3q21 and rs17181170/3p12). Among 666 variants in the 55 regions with P-values within one order of magnitude of the most-associated marker, 193 variants (29%) in 48 regions overlapped with epigenetic or other putative functional marks. In 11 of the 55 regions, cis-eQTLs were detected with nearby genes. For 12 of the 55 regions (22%), the most significant region-specific, prostate-cancer associated variant represented the strongest candidate functional variant based on our annotations; the number of regions increased to 20 (36%) and 27 (49%) when examining the 2 and 3 most significantly associated variants in each region, respectively. These results have prioritized subsets of candidate variants for downstream functional evaluation., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Purpose: The study objective was to examine the role of physical activity (PA) and sedentary time (ST) on mortality risk among a population of low-income adults with diabetes., Methods: Black (n = 11,137) and white (n = 4508) men and women with diabetes from the Southern Community Cohort Study self-reported total PA levels and total ST. Participants were categorized into quartiles of total PA and total ST. Hazard ratios (HRs) and 95% confidence intervals (CIs) for subsequent mortality risk were estimated from Cox proportional hazards analysis with adjustment for potential confounders., Results: During follow-up, 2370 participants died. The multivariable risk of mortality was lower among participants in the highest quartile of PA compared with those in the lowest quartile (HR, 0.64; 95% CI: 0.57-0.73). Mortality risk was significantly increased among participants in the highest compared with the lowest quartile of ST after adjusting for PA (HR, 1.21; 95% CI: 1.08-1.37). Across sex and race groups, similar trends of decreasing mortality with rising PA and increasing mortality with rising ST were observed., Conclusions: Although causality cannot be established from these observational data, the current findings suggest that increasing PA and decreasing ST may help extend survival among individuals with diabetes irrespective of race and sex., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Height has an extremely polygenic pattern of inheritance. Genome-wide association studies (GWAS) have revealed hundreds of common variants that are associated with human height at genome-wide levels of significance. However, only a small fraction of phenotypic variation can be explained by the aggregate of these common variants. In a large study of African-American men and women (n = 14,419), we genotyped and analyzed 966,578 autosomal SNPs across the entire genome using a linear mixed model variance components approach implemented in the program GCTA (Yang et al Nat Genet 2010), and estimated an additive heritability of 44.7% (se: 3.7%) for this phenotype in a sample of evidently unrelated individuals. While this estimated value is similar to that given by Yang et al in their analyses, we remain concerned about two related issues: (1) whether in the complete absence of hidden relatedness, variance components methods have adequate power to estimate heritability when a very large number of SNPs are used in the analysis; and (2) whether estimation of heritability may be biased, in real studies, by low levels of residual hidden relatedness. We addressed the first question in a semi-analytic fashion by directly simulating the distribution of the score statistic for a test of zero heritability with and without low levels of relatedness. The second question was addressed by a very careful comparison of the behavior of estimated heritability for both observed (self-reported) height and simulated phenotypes compared to imputation R2 as a function of the number of SNPs used in the analysis. These simulations help to address the important question about whether today's GWAS SNPs will remain useful for imputing causal variants that are discovered using very large sample sizes in future studies of height, or whether the causal variants themselves will need to be genotyped de novo in order to build a prediction model that ultimately captures a large fraction of the variability of height, and by implication other complex phenotypes. Our overall conclusions are that when study sizes are quite large (5,000 or so) the additive heritability estimate for height is not apparently biased upwards using the linear mixed model; however there is evidence in our simulation that a very large number of causal variants (many thousands) each with very small effect on phenotypic variance will need to be discovered to fill the gap between the heritability explained by known versus unknown causal variants. We conclude that today's GWAS data will remain useful in the future for causal variant prediction, but that finding the causal variants that need to be predicted may be extremely laborious.

Genome-wide association studies have identified more than 80 risk variants for prostate cancer, mainly in European or Asian populations. The generalizability of these variants in other racial/ethnic populations needs to be understood before the loci can be used widely in risk modeling. In our study, we examined 82 previously reported risk variants in 4,853 prostate cancer cases and 4,678 controls of African ancestry. We performed association testing for each variant using logistic regression adjusted for age, study and global ancestry. Of the 82 known risk variants, 68 (83%) had effects that were directionally consistent in their association with prostate cancer risk and 30 (37%) were significantly associated with risk at p < 0.05, with the most statistically significant variants being rs116041037 (p = 3.7 × 10(-26) ) and rs6983561 (p = 1.1 × 10(-16) ) at 8q24, as well as rs7210100 (p = 5.4 × 10(-8) ) at 17q21. By exploring each locus in search of better markers, the number of variants that captured risk in men of African ancestry (p < 0.05) increased from 30 (37%) to 44 (54%). An aggregate score comprised of these 44 markers was strongly associated with prostate cancer risk [per-allele odds ratio (OR) = 1.12, p = 7.3 × 10(-98) ]. In summary, the consistent directions of effects for the vast majority of variants in men of African ancestry indicate common functional alleles that are shared across populations. Further exploration of these susceptibility loci is needed to identify the underlying biologically relevant variants to improve prostate cancer risk modeling in populations of African ancestry., (© 2014 UICC.)

Prior studies of risk factors associated with external causes of death have been limited in the number of covariates investigated and external causes examined. Herein, associations between numerous demographic, lifestyle, and health-related factors and the major causes of external mortality, such as suicide, homicide, and accident, were assessed prospectively among 73,422 black and white participants in the Southern Community Cohort Study (SCCS). Hazard ratios (HR) and 95% confidence intervals (CI) were calculated in multivariate regression analyses using the Cox proportional hazards model. Men compared with women (HR = 2.32; 95% CI: 1.87-2.89), current smokers (HR = 1.74; 95% CI: 1.40-2.17), and unemployed/never employed participants at the time of enrollment (HR = 1.67; 95% CI 1.38-2.02) had increased risk of dying from all external causes, with similarly elevated HRs for suicide, homicide, and accidental death among both blacks and whites. Blacks compared with whites had lower risk of accidental death (HR = 0.46; 95% CI: 0.38-0.57) and suicide (HR = 0.55; 95% CI: 0.31-0.99). Blacks and whites in the SCCS had comparable risks of homicide death (HR = 1.05; 95% CI: 0.63-1.76); however, whites in the SCCS had unusually high homicide rates compared with all whites who were resident in the 12 SCCS states, while black SCCS participants had homicide rates similar to those of all blacks residing in the SCCS states. Depression was the strongest risk factor for suicide, while being married was protective against death from homicide in both races. Being overweight/obese at enrollment was associated with reduced risks in all external causes of death, and the number of comorbid conditions was a risk factor for iatrogenic deaths. Most risk factors identified in earlier studies of external causes of death were confirmed in the SCCS cohort, in spite of the low SES of SCCS participants. Results from other epidemiologic cohorts are needed to confirm the novel findings identified in this study.

The extent of recent selection in admixed populations is currently an unresolved question. We scanned the genomes of 29,141 African Americans and failed to find any genome-wide-significant deviations in local ancestry, indicating no evidence of selection influencing ancestry after admixture. A recent analysis of data from 1,890 African Americans reported that there was evidence of selection in African Americans after their ancestors left Africa, both before and after admixture. Selection after admixture was reported on the basis of deviations in local ancestry, and selection before admixture was reported on the basis of allele-frequency differences between African Americans and African populations. The local-ancestry deviations reported by the previous study did not replicate in our very large sample, and we show that such deviations were expected purely by chance, given the number of hypotheses tested. We further show that the previous study's conclusion of selection in African Americans before admixture is also subject to doubt. This is because the FST statistics they used were inflated and because true signals of unusual allele-frequency differences between African Americans and African populations would be best explained by selection that occurred in Africa prior to migration to the Americas., (Copyright © 2014 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

There is limited evidence demonstrating the benefits of physical activity with regard to mortality risk or the harms associated with sedentary behavior in black adults, so we examined the relationships between these health behaviors and cause-specific mortality in a prospective study that had a large proportion of black adults. Participants (40-79 years of age) enrolled in the Southern Community Cohort Study between 2002 and 2009 (n = 63,308) were prospectively followed over 6.4 years, and 3,613 and 1,394 deaths occurred in blacks and whites, respectively. Black adults who reported the highest overall physical activity level (≥32.3 metabolic equivalent-hours/day vs. <9.7 metabolic equivalent-hours/day) had lower risks of death from all causes (hazard ratio (HR) = 0.76. 95% confidence interval (CI): 0.69, 0.85), cardiovascular disease (HR = 0.81, 95% CI: 0.67, 0.98), and cancer (HR = 0.76, 95% CI: 0.62, 0.94). In whites, a higher physical activity level was associated with a lower risk of death from all causes (HR = 0.76, 95% CI: 0.64, 0.90) and cardiovascular disease (HR = 0.69, 95% CI: 0.49, 0.99) but not cancer (HR = 0.95, 95% CI: 0.67, 1.34). Spending more time being sedentary (>12 hours/day vs. <5.76 hours/day) was associated with a 20%-25% increased risk of all-cause mortality in blacks and whites. Blacks who reported the most time spent being sedentary (≥10.5 hours/day) and lowest level of physical activity (<12.6 metabolic equivalent-hours/day) had a greater risk of death (HR = 1.47, 95% CI: 1.25, 1.71). Our study provides evidence that suggests that health promotion efforts to increase physical activity level and decrease sedentary time could help reduce mortality risk in black adults., (Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health 2014. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

Background: Lifestyle and socioeconomic status have been implicated in the prevalence of hypertension; thus, we evaluated factors associated with hypertension in a cohort of blacks and whites with similar socioeconomic status characteristics., Methods and Results: We evaluated the prevalence and factors associated with self-reported hypertension (SR-HTN) and ascertained hypertension (A-HTN) among 69,211 participants in the Southern Community Cohort Study. Multivariable logistic regression models were used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for factors associated with hypertension. The prevalence of SR-HTN was 57% overall. Body mass index was associated with SR-HTN in all race-sex groups, with the OR rising to 4.03 (95% CI, 3.74-4.33) for morbidly obese participants (body mass index, >40 kg/m(2)). Blacks were more likely to have SR-HTN than whites (OR, 1.84; 95% CI, 1.75-1.93), and the association with black race was more pronounced among women (OR, 2.08; 95% CI, 1.95-2.21) than men (OR, 1.47; 95% CI, 1.36-1.60). Similar findings were noted in the analysis of A-HTN. Among those with SR-HTN and A-HTN who reported use of an antihypertensive agent, 94% were on at least one of the major classes of antihypertensive agents, but only 44% were on ≥2 classes and only 29% were on a diuretic. The odds of both uncontrolled hypertension (SR-HTN and A-HTN) and unreported hypertension (no SR-HTN and A-HTN) were twice as high among blacks as whites (OR, 2.13; 95% CI, 1.68-2.69; and OR, 1.99; 95% CI, 1.59-2.48, respectively)., Conclusions: Despite socioeconomic status similarities, we observed suboptimal use of antihypertensives in this cohort and racial differences in the prevalence of uncontrolled and unreported hypertension, which merit further investigation.

Introduction: Few lung cancer studies have focused on lung cancer survival in underserved populations. We conducted a prospective cohort study among 81,697 racially diverse and medically underserved adults enrolled in the Southern Community Cohort Study throughout an 11-state area of the Southeast from March 2002 to September 2009., Methods: Using linkages with state cancer registries, we identified 501 incident non-small-cell lung cancer cases. We applied Cox proportional hazards models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for subsequent mortality among black and white participants., Results: The mean observed follow-up time (the time from diagnosis to death or end of follow-up) was 1.25 years (range, 0-8.3 years) and 75% (n = 376) of cases died during follow-up. More blacks were diagnosed at distant stage than whites (57 versus 45%; p = 0.03). In multivariable analyses adjusted for pack-years of smoking, age, body mass index, health insurance, socioeconomic status and disease stage, the lung cancer mortality HR was higher for men versus women (HR = 1.41; 95% CI, 1.09-1.81) but similar for blacks versus whites (HR = 0.99; 95% CI, 0.74-1.32)., Conclusion: These findings suggest that although proportionally more blacks present with distant-stage disease there is no difference in stage-adjusted lung cancer mortality between blacks and whites of similar low socioeconomic status.

Despite a greater burden of traditional risk factors, atrial fibrillation (AF) is less common among blacks than whites for reasons that are unclear. The aim of this study was to examine race- and gender-specific influences of demographic, lifestyle, anthropometric, and medical factors on AF in a large cohort of blacks and whites. Among white and black participants in the Southern Community Cohort Study (SCCS) aged ≥65 years receiving Medicare coverage from 1999 to 2008 (n = 8,836), diagnoses of AF (International Classification of Diseases, Ninth Revision, Clinical Modification code 427.3) were ascertained. Multivariate logistic regression was used to compute AF odds ratios associated with participant characteristics, including histories of hypertension, diabetes, stroke, and myocardial infarction or coronary artery bypass graft surgery, ascertained at cohort entry. Over an average of 5.7 years of Medicare coverage, AF was diagnosed in 1,062 participants. AF prevalence was significantly lower among blacks (11%) than whites (15%) (p <0.0001). Odds ratios for AF increased with age and were higher among men, the tall and obese, and patients with each of the co-morbid conditions, but the AF deficit among blacks compared to whites persisted after adjustment for these factors (odds ratio 0.64, 95% confidence interval 0.55 to 0.73). The patterns of AF risk were similar for blacks and whites, although associations with hypertension, diabetes, and stroke were somewhat stronger among blacks. In conclusion, these findings confirm the lower prevalence of AF among blacks than whites and suggest that traditional risk factors for AF apply similarly to the 2 groups and thus do not appear to explain the AF paradox in blacks., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Purpose: The authors recently reported high Helicobacter pylori sero-prevalence among African-Americans of high African ancestry. We sought to determine whether neighborhood-level socio-economic characteristics are associated with H. pylori prevalence and whether this helps explain the link between African ancestry and H. pylori., Methods: Antibodies to H. pylori proteins were assessed in the serum of 336 African-American and 329 white Southern Community Cohort Study participants. Prevalence odds ratios (ORs) and 95 % confidence intervals (CIs) for CagA+ and CagA- H. pylori were calculated using polytomous logistic regression in relation to 10 Census block group-level measures of socio-economic status., Results: After adjusting for individual-level characteristics, three neighborhood-level factors were significantly inversely related to CagA+ H. pylori: percent completed high school; median house values; and percent employed (comparing highest to lowest tertile, OR, 0.47, 95 % CI, 0.26-0.85; OR, 0.56, 95 % CI, 0.32-0.99; and OR, 0.59, 95 % CI, 0.34-1.03, respectively). However, accounting for these measures did not attenuate the association between African ancestry and CagA+ H. pylori, with African-Americans of low, medium, and high African ancestry maintaining two-, seven-, and ninefold increased odds, respectively, compared to whites., Conclusions: Neighborhood-level measures of education, employment, and house values are associated with CagA+ H. pylori sero-prevalence, but do not explain the persistent strong relationship between African ancestry level and CagA+ H. pylori. The findings suggest that neighborhood socio-economic status can help to highlight high-risk areas for prevention and screening efforts and that the link between African ancestry and H. pylori may have a biological basis.

Purpose: To examine whether body mass index is associated with reduced colorectal cancer (CRC) screening in a large population of black and white adults., Methods: Cross-sectional data collected at baseline for 9,547 black men, 14,515 black women, 3,519 white men, and 7,245 white women aged 50-79 enrolled in the Southern Community Cohort Study from 2002 to 2009 were used to examine odds ratios (OR) with 95 % confidence intervals (CI) for the use of colonoscopy or sigmoidoscopy in relation to body mass index (BMI) categories (<18.5, 18.5-24.9 (referent), 25-29.9, 30-34.9, 35-39.9, and 40+ (extreme obesity), kg/m(2)) using logistic regression controlling for age, education, income, health insurance status, last physician visit, cigarette smoking, and alcohol consumption., Results: Increased BMI was not associated with reduced CRC screening among whites (OR (95 % CI) for BMI ≥ 40 = 1.02 (0.71-1.46) for white men and 0.99 (0.83-1.19) for white women), and odds of CRC screening were increased with high BMI among blacks (OR (95 % CI) for BMI ≥ 40 = 1.34 (1.03-1.74) for black men and 1.13 (0.98-1.29) for black women). Extreme obesity was associated with reduced odds of CRC screening only among white women in subgroup analyses limited to those with health insurance or income ≥$25,000/year., Conclusions: Elevated BMI was not a deterrent to CRC screening overall in this population. In light of low overall screening rates for colorectal cancer nationally, efforts to increase screening in all individuals should remain the focus of public health initiatives.

Background: Gastric cancer incidence in African Americans is twice that of whites, and differing prevalence of Helicobacter pylori strain-specific isolates may help explain the disparity., Methods: Serum levels of antibodies to each of 15 H. pylori proteins were assessed using multiplex serology for a sample of 689 African American and white participants from the Southern Community Cohort Study. African and European admixture was estimated using a panel of 276 ancestry genetic markers, with "low," "medium," and "high" categories of African ancestry defined as <85%, 85% to 95%, and ≥95%., Results: The majority (79%) of our study population were sero-positive for H. pylori. African American race was associated with a two- to sixfold increased odds for sero-positivity to eight H. pylori proteins, including the cancer-associated virulence constituents CagA [odds ratio (OR), 6.4; 95% CI, 4.5-9.1], and VacA (OR, 2.3; 95% CI, 1.5-3.5). Compared to whites, African Americans of low, medium, and high African ancestry had 1.6-, 4.1-, and 5.2-fold increased odds of sero-positivity to H. pylori, primarily related to CagA sero-positive strains, for which increasing African ancestry led to 2.5-, 9.6-, and 13.1-fold increased odds. Among African Americans alone, compared to those of low African ancestry, African Americans of medium and high African ancestry had 2.5- and 3.4-fold increased odds of sero-positivity to H. pylori, and 3.5- and 4.9-fold increased odds of CagA sero-positive H. pylori strains., Conclusions: Host genetic variation and/or lifestyle factors associated with African ancestry contribute to the likelihood of infection with H. pylori, particularly its virulent strains, in this low-income U.S. southern population., Impact: Our findings that low-income African Americans of high African ancestry have a particularly high prevalence of antibodies against H. pylori provides a framework for further research into better detection and prevention of gastric cancer in this population., (©2011 AACR.)

Obesity and black race have been associated with excess risk of multiple myeloma. The association of obesity with monoclonal gammopathy of undetermined significance (MGUS) is unknown. Further, it is not known whether the increased risk of multiple myeloma and MGUS in blacks is related to socioeconomic status, genetic susceptibility, or both. We screened 1000 black and 996 white women (range, 40-79 years) of similar socioeconomic status for MGUS; the aim of the study was to assess MGUS risk in relation to obesity and race. A total of 39 (3.9%) blacks and 21 (2.1%) whites had MGUS. On multivariate analysis, obesity (odds ratio [OR] = 1.8; P = .04), black race (OR = 1.8; P = .04), and increasing age (> 55 vs < 43 years; OR = 2.5; P = .03) were independently associated with an excess risk of MGUS. Our findings support the hypothesis that obesity is etiologically linked to myelomagenesis. The 2-fold excess of MGUS among blacks compared with whites of similar socioeconomic status supports a role for susceptibility genes in MGUS.

Objective: This research sought to describe associations among parity, breastfeeding, and adult obesity in black and white women in the southeastern United States., Methods: Cross-sectional data from 7,986 white women and 23,198 black women (age 40-79 years) living in the southeastern United States and enrolled in the Southern Community Cohort Study during 2002-2006 were used to examine self-reported body mass index (BMI) and weight change since age 21 in association with parity and breastfeeding. Multiple linear regression and logistic regression with adjustment for demographic and lifestyle factors were used., Results: At all levels of parity and breastfeeding, black women had higher BMI and weight gain since age 21 than white women. Compared to nulliparity, five or more live births was associated with increased odds of obesity in white women (odds ratio [OR] = 1.37, 95% confidence interval [CI] = 1.08-1.74) and, to a lesser extent, in black women (OR = 1.22, 95% CI = 1.07-1.38). In white women, breastfeeding for more than 12 months compared to none was associated with decreased odds of obesity (OR = 0.68, 95% CI = 0.56-0.82), whereas in black women, no association between obesity and breastfeeding was seen., Conclusions: The associations between childbearing factors and measures of adult obesity appear to be larger in white women compared to black women but relatively small overall. However, when considered as part of the constellation of factors that lead to obesity, even these small associations may be important in an overall obesity prevention strategy.

The purpose of this study was to estimate black/white differences in cotinine levels for current smokers of both sexes, and to explore the potential contribution of mentholated cigarettes to these differences. Sera from 255 current smokers sampled from Southern Community Cohort Study participants (65 black men, 65 black women, 63 white men, 62 white women) were analyzed for cotinine, and linear regression was used to model the effect of race on cotinine level, adjusting for the number of cigarettes smoked within the last 24 hours, use of menthol vs. non-menthol cigarettes, exposure to environmental tobacco smoke, and age. Black smokers smoked fewer cigarettes than white smokers, yet had crude mean cotinine levels nearly as high or higher than white smokers. After multivariate adjustment, cotinine levels were an average of 50 ng/ml higher among black than white women (p=0.008) and non-significantly 12 ng/ml higher among black than white men (p=0.52). We observed no increase in cotinine levels associated with menthol cigarette use. We conclude that differences in cotinine levels among smokers suggest racial variation in exposure to and/or metabolism of tobacco smoke constituents, but our findings do not support a role for menthol preference in this disparity.

Objective: To examine the relationship between obesity and mammography use in a large population of black and white women., Methods: Baseline data from 18,756 black and 6,304 white women enrolled in the Southern Community Cohort Study were used to examine the association between body mass index categories (healthy weight: 18.5-24.9 kg/m(2), overweight: 25-29.9 kg/m(2), and obesity classes I: 30-34.9 kg/m(2), II: 35-39.9 kg/m(2), and III: 40+ kg/m(2)) and mammogram use in the past two years. Cross-sectional analyses were conducted using logistic regression controlling for socioeconomic measures, medical conditions, insurance coverage, and lifestyle factors., Results: Among white women, obesity class III was associated with a reduced likelihood of recent mammography compared to healthy weight women (OR = 0.70, 95% CI 0.56-0.87) that appeared unrelated to income and insurance coverage. A deterring effect of obesity was not evident among black women; instead, overweight and obesity were associated with small elevations in mammography use compared to healthy weight., Conclusions: In light of rising obesity rates and known associations between obesity and breast cancer risk and prognosis, a deterring effect of extreme obesity on mammography screening for white women is a concern that should be addressed by screening programs and by further directed research into the factors underlying this association.

Genome-wide association studies (GWAS) have identified >300 loci associated with measures of adiposity including body mass index (BMI) and waist-to-hip ratio (adjusted for BMI, WHRadjBMI), but few have been identified through screening of the African ancestry genomes. We performed large scale meta-analyses and replications in up to 52,895 individuals for BMI and up to 23,095 individuals for WHRadjBMI from the African Ancestry Anthropometry Genetics Consortium (AAAGC) using 1000 Genomes phase 1 imputed GWAS to improve coverage of both common and low frequency variants in the low linkage disequilibrium African ancestry genomes. In the sex-combined analyses, we identified one novel locus (TCF7L2/HABP2) for WHRadjBMI and eight previously established loci at P < 5×10-8: seven for BMI, and one for WHRadjBMI in African ancestry individuals. An additional novel locus (SPRYD7/DLEU2) was identified for WHRadjBMI when combined with European GWAS. In the sex-stratified analyses, we identified three novel loci for BMI (INTS10/LPL and MLC1 in men, IRX4/IRX2 in women) and four for WHRadjBMI (SSX2IP, CASC8, PDE3B and ZDHHC1/HSD11B2 in women) in individuals of African ancestry or both African and European ancestry. For four of the novel variants, the minor allele frequency was low (

Despite recent progress on estimating the heritability explained by genotyped SNPs (h(2)g), a large gap between h(2)g and estimates of total narrow-sense heritability (h(2)) remains. Explanations for this gap include rare variants or upward bias in family-based estimates of h(2) due to shared environment or epistasis. We estimate h(2) from unrelated individuals in admixed populations by first estimating the heritability explained by local ancestry (h(2)γ). We show that h(2)γ = 2FSTCθ(1 - θ)h(2), where FSTC measures frequency differences between populations at causal loci and θ is the genome-wide ancestry proportion. Our approach is not susceptible to biases caused by epistasis or shared environment. We applied this approach to the analysis of 13 phenotypes in 21,497 African-American individuals from 3 cohorts. For height and body mass index (BMI), we obtained h(2) estimates of 0.55 ± 0.09 and 0.23 ± 0.06, respectively, which are larger than estimates of h(2)g in these and other data but smaller than family-based estimates of h(2).

Purpose: To evaluate the association between obesity and the relative prevalence of tumor subtypes among Black women with breast cancer (BC). Methods: We conducted a pooled case-only analysis of 1,793 Black women with invasive BC recruited through three existing studies in the southeastern US. Multivariable case-only polytomous logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the association between obesity, measured by pre-diagnostic body mass index (BMI), and human epidermal growth factor receptor 2 + (HER2 +) and triple negative BC (TNBC) subtype relative to hormone receptor (HR) + /HER2- status (referent). Results: Among 359 premenopausal women, 55.4% of cases were HR + /HER2 −, 20.1% were HER2 + , and 24.5% were TNBC; corresponding percentages among 1,434 postmenopausal women were 59.3%, 17.0%, and 23.6%. Approximately, 50–60% of both pre- and postmenopausal women were obese (BMI > 30 kg/m2), regardless of BC subtype. We did not observe a significant association between obesity and BC subtype. Among postmenopausal women, class I obesity (BMI 35 + kg/m2) was not associated with the development of HER2 + BC (OR 0.69; 95% CI 0.42–1.14) or TNBC (OR 0.93; 95% CI 0.60–1.45) relative to HR + /HER2- tumors. Corresponding estimates among premenopausal women were 1.03 (95% CI 0.43–2.48) and 1.13 (95% CI 0.48–2.64). Conclusion: In this large study of Black women with BC, there was no evidence of heterogeneity of BMI by BC subtype. [ABSTRACT FROM AUTHOR]

Purpose: Helicobacter pylori (H. pylori) is the leading cause of gastric cancer. High antibody levels to H. pylori virulence factors Vacuolating cytotoxin A (VacA) and Cytotoxin-associated gene A (CagA) have been suggested as gastric cancer risk markers. In the USA, H. pylori sero-prevalence is twofold higher in African Americans compared to whites. We sought to assess whether African Americans also exhibit higher antibody levels to VacA and CagA.Methods: Antibody responses to H. pylori proteins were measured by multiplex serology in 686 African Americans and whites of the Southern Community Cohort Study. Among VacA- and CagA-seropositives, we analyzed the association of race with antibody level using logistic regression models to produce odds ratios (OR) and 95% confidence intervals (CI).Results: Sero-positive African Americans had significantly higher mean antibody levels to both VacA and CagA, which resulted in increased odds for the highest quartile of antibody levels compared to sero-positive whites (VacA, OR: 6.08; 95% CI 3.41, 10.86; CagA, OR: 3.77; 95% CI 1.61, 8.84).Conclusion: Our findings support future studies to assess the association of differential antibody responses by race with risk of gastric cancer in the USA, which could then aid in developing targeted H. pylori eradication strategies. [ABSTRACT FROM AUTHOR]

Purpose: We prospectively examined associations of lung cancer risk with food intake of B vitamins involved in one-carbon metabolism and the use of folic acid-containing supplements among a low-income population of black and white adults in the Southeastern US. Methods: Within the Southern Community Cohort Study, we included 1064 incident lung cancer cases among 68,236 participants aged 40–79 years at study enrollment. Food intake and the use of folic acid-containing supplements were assessed using a validated food frequency questionnaire at study enrollment. Multivariate Cox regression was used to estimate hazards ratios (HRs) and the 95% confidence intervals (CIs). Results: Folate and/or folic acid intake from food were not associated with lung cancer risk; HRs (95% CI) for highest compared with lowest quartile were 1.08 (0.91–1.29) for total dietary folate, 1.00 (0.84–1.19) for food folate, and 1.09 (0.91–1.30) for food folic acid, respectively. Similarly, no associations were observed after stratifying by sex, race and smoking status, except for a positive association with total dietary folate intake among black women (HR 1.46, 95% CI 1.04–2.05 for the highest quartile compared with the lowest quartile, P trend = 0.02). Neither the use of folic acid-containing supplements nor food intake of vitamin B6, vitamin B12 and riboflavin were associated with lung cancer risk. Conclusions: Our findings do not support a protective effect of folate or folic acid for lung cancer prevention in a low-income population of black and white adults in the Southeastern US. Our finding of a positive association with total dietary folate intake among black women needs to be interpreted with caution and replicated in other studies. [ABSTRACT FROM AUTHOR]

Background Breast cancer–related lymphedema (BCRL) is a well-known side effect of cancer and its treatment with wide-ranging prevalence estimates. Objective This study describes associations between breast cancer–related lymphedema (BCRL) signs, symptoms, and diagnosis for women who were African American, white, or had a low income and survived breast cancer. Design This is a cross-sectional, observational study that used a computer-assisted telephone interview. Methods Women who had survived breast cancer were queried on the presence of 5 lymphedema signs and symptoms (edema in the breast, axilla, arm, and/or hand; tissue fibrosis; pitting; hemosiderin staining; heaviness) and whether they had a diagnosis of BCRL. Relationships between signs/symptoms and diagnosis for each group were evaluated with kappa and chi-square statistics. Results The study sample included 528 women who had survived breast cancer (266 white and 262 African American), with 514 reporting complete data on household income; 45% of the latter reported an annual household income of ≤$20,000. Women who were African American or had a low income were nearly twice as likely as women who were white to have any of 8 signs/symptoms of BCRL. Regardless of race and income, >50% of women with all BCRL signs and symptoms reported that they were not diagnosed with BCRL. Limitations The main limitations of our study are the lack of medical chart data and longitudinal design. Conclusions Women who were African American or had a low income and had survived breast cancer had a greater burden of BCRL signs and symptoms than women who were white. The lack of a strong association between BCRL signs, symptoms, and diagnosis suggests that BCRL may be underdiagnosed. These findings suggest that more rigorous screening and detection of BCRL—especially for women who are African American or have a low income—may be warranted. Cancer rehabilitation programs may be able to fill this gap. [ABSTRACT FROM AUTHOR]

Background Choline-related nutrients are dietary precursors of a gut microbial metabolite, trimethylamine-N-oxide, which has been linked to cardiometabolic diseases and related death. However, epidemiologic evidence on dietary choline and mortality remains limited, particularly among nonwhite populations. Objectives This study aimed to investigate the associations of choline-related nutrients with cardiometabolic and all-cause mortality among black and white Americans and Chinese adults. Methods Included were 49,858 blacks, 23,766 whites, and 134,001 Chinese, aged 40–79 y, who participated in 3 prospective cohorts and lived ≥1 y after enrollment. Cox regression models were used to estimate HRs and 95% CIs for cardiometabolic [e.g., ischemic heart disease (IHD), stroke, and diabetes] and all-cause deaths. To account for multiple testing, P values < 0.003 were considered significant. Results Mean choline intake among blacks, whites, and Chinese was 404.1 mg/d, 362.0 mg/d, and 296.8 mg/d, respectively. During a median follow-up of 11.7 y, 28,673 deaths were identified, including 11,141 cardiometabolic deaths. After comprehensive adjustments, including for overall diet quality and disease history, total choline intake was associated with increased cardiometabolic mortality among blacks and Chinese (HR for highest compared with lowest quintile: 1.26; 95% CI: 1.13, 1.40 and HR: 1.23; 95% CI: 1.11, 1.38, respectively; both P -trend < 0.001); among whites, the association was weaker (HR: 1.12; 95% CI: 0.95, 1.33; P -trend = 0.02). Total choline intake was also associated with diabetes and all-cause mortality in blacks (HR: 1.66; 95% CI: 1.26, 2.19 and HR: 1.20; 95% CI: 1.12, 1.29, respectively), with diabetes mortality in Chinese (HR: 2.24; 95% CI: 1.68, 2.97), and with IHD mortality in whites (HR: 1.31; 95% CI: 1.02, 1.69) (all P -trend < 0.001). The choline–mortality association was modified by alcohol consumption and appeared stronger among individuals with existing cardiometabolic disease. Betaine intake was associated with increased cardiometabolic mortality in Chinese only (HR: 1.16; 95% CI: 1.08, 1.25; P -trend < 0.001). Conclusions High choline intake was associated with increased cardiometabolic mortality in racially diverse populations. [ABSTRACT FROM AUTHOR]

Abstract Objective. To determine associations of adverse childhood experiences (ACE) with adult health care utilization in an underserved, low-income population. Methods. Questionnaires on ACE were completed by 38,200 adults (mean age 54), two-thirds African American, recruited from community health centers (CHCs) across 12 Southeastern states. Odds ratios (ORs) and accompanying 95% confidence intervals (CIs) were computed. Results. The percentages reporting emergency room visits and doctor's office visits, with high chronic disease index scores, rose monotonically (ptrend<.001) with rising ACE score. Odds ratios (CIs) for those with four or more vs. zero ACEs were 1.37 (95% CI 1.27–1.47) for 1–10 times and 1.80 (95% CI 1.29–2.52) for more than 10 times ER visits, 1.37 (95% CI 1.18–1.59) for over 10 doctor's visits, and 2.29 (95% CI 2.06–2.54) for three or more chronic diseases. Conclusions. High ACE levels were associated with greater chronic disease burden and greater health care utilization in adulthood. Long-lasting effects from ACE on the health care of underserved populations are indicated. There is an urgent need to train health care providers, patients, and their families on ACE effects and treatments for better health care outcomes. [ABSTRACT FROM AUTHOR]

Objectives. We evaluated the independent and joint effects of race, individual socioeconomic status (SES), and neighborhood SES on mortality risk. Methods. We conducted a prospective analysis involving 52 965 non-Hispanic Black and 23 592 non-Hispanic White adults taking part in the Southern Community Cohort Study. Cox proportional hazards modeling was used to determine associations of race and SES with all-cause and cause-specific mortality. Results. In our cohort, wherein Blacks and Whites had similar individual SES, Blacks were less likely than Whites to die during the follow-up period (hazard ratio [HR] = 0.78; 95% confidence interval [CI] = 0.73, 0.84). Low household income was a strong predictor of all-cause mortality among both Blacks and Whites (HR = 1.76; 95% CI = 1.45, 2.12). Being in the lowest (vs highest) category with respect to both individual and neighborhood SES was associated with a nearly 3-fold increase in all-cause mortality risk (HR = 2.76; 95% CI = 1.99, 3.84). There was no significant mortality-related interaction between individual SES and neighborhood SES among either Blacks or Whites. Conclusions. SES is a strong predictor of premature mortality, and the independent associations of individual SES and neighborhood SES with mortality risk are similar for Blacks and Whites. [ABSTRACT FROM AUTHOR]

The beneficial biologic effects attributed to vitamin D suggest a potential to influence overall mortality. Evidence addressing this hypothesis is limited, especially for African Americans who have a high prevalence of vitamin D insufficiency. The authors conducted a nested case-control study within the prospective Southern Community Cohort Study to relate baseline serum levels of 25-hydroxyvitamin D (25(OH)D) with subsequent mortality. Cases were 1,852 participants who enrolled from 2002 to 2009 and died >12 months postenrollment. Controls (n = 1,852) were matched on race, sex, age, enrollment site, and blood collection date. The odds ratios for quartile 1 (<10.18 ng/mL) versus quartile 4 (>21.64 ng/mL) levels of 25(OH)D were 1.60 (95% confidence interval (CI): 1.20, 2.14) for African Americans and 2.11 (95% CI: 1.39, 3.21) for non-African Americans. The effects were strongest for circulatory disease death, where quartile 1 versus quartile 4 odds ratios were 2.53 (95% CI: 1.44, 4.46) and 3.25 (95% CI: 1.33, 7.93) for African Americans and non-African Americans, respectively. The estimated odds of total mortality were minimized in the 25(OH)D range of 35–40 ng/mL. These findings provide support for the hypothesis that vitamin D status may have an important influence on mortality for both African Americans and non-African Americans. [ABSTRACT FROM PUBLISHER]

Type 2 diabetes (T2D) is up to twice as prevalent among African Americans as Caucasians. Recent genome-wide association studies (GWAS) have identified multiple common genetic risk variants for T2D; however, none of these studies were conducted exclusively among subjects of African ancestry. Investigating these known loci in other populations would be an expedient way to evaluate the generalizability of the current findings. The authors evaluated 29 known T2D loci in a large southeastern US cohort study including 4,288 African Americans (1,554 cases and 2,734 controls) enrolled during 2002–2009. Seven of the 29 single nucleotide polymorphisms (SNPs) examined were found to be associated with T2D risk at P ≤ 0.05, including rs6769511 (IGF2BP2), 2 SNPs in the WFS1 gene (rs4689388 and rs1801214), rs7903146 (TCF7L2), and 3 SNPs in the KCNQ1 gene (rs231362, rs2237892, and rs2237897). Notably, the association for rs7903146 reached the GWAS significance level (P = 3.6 × 10−8), with an odds ratio per T allele of 1.32 (95% confidence interval: 1.20, 1.46). Regional analyses using GWAS data from Vanderbilt University's BioVU DNA biobank showed significant associations (P < 0.05) with 9 loci, though no association was observed for the index SNPs reported in European- or Asian-ancestry populations. These results extend some of the recent GWAS findings to African Americans and may guide future efforts to identify causal variants for T2D. [ABSTRACT FROM PUBLISHER]

Prospective epidemiologic studies generally rely on 1 baseline biologic sample from participants for measurement of prediagnostic biomarkers, assuming that 1 measurement adequately represents the participant's “typical” level. The body of work assessing the reproducibility of circulating serum 25-hydroxyvitamin D (25(OH)D) levels over time focuses almost exclusively on populations of European descent, and data for vitamin D-binding protein (VDBP) are virtually nonexistent. Thus, the authors measured levels of serum 25(OH)D and VDBP twice in samples collected between 2005 and 2008 from 225 participants (155 black, 70 white) in the Southern Community Cohort Study. Reproducibility for 25(OH)D was uniformly high, with adjusted intraclass correlation coefficients (ICCs) of 0.84 (95% confidence interval (CI): 0.79, 0.88) for blacks and 0.92 (95% CI: 0.87, 0.95) for whites, and there was substantial agreement for assignment of 25(OH)D quartile (κ = 0.83, 95% CI: 0.78, 0.87) and vitamin D adequacy status (κ = 0.76, 95% CI: 0.69, 0.83). VDBP levels were highly stable over time, with adjusted ICCs of 0.97 (95% CI: 0.96, 0.98) for blacks and 0.96 (95% CI: 0.93, 0.97) for whites. These findings suggest that single, baseline 25(OH)D and VDBP serum measurements provide reasonably representative measures of these compounds for both white and black adults, demonstrating their utility as epidemiologic biomarkers in prospective studies. [ABSTRACT FROM PUBLISHER]

We evaluated whether black race is associated with higher incidence of End Stage Renal Disease (ESRD) among a cohort of blacks and whites of similar, generally low socioeconomic status, and whether risk factor patterns differ among blacks and whites and explain the poorly understood racial disparity in ESRD. Incident diagnoses of ESRD among 79,943 black and white participants in the Southern Community Cohort Study (SCCS) were ascertained by linkage with the United States Renal Data System (USRDS) from 2002 through 2009. Person-years of follow up were calculated from date of entry into the SCCS until date of ESRD diagnosis, date of death, or September 1, 2009, whichever occurred first. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CI) for incident ESRD among black and white participants in relation to baseline characteristics. After 329,003 person-years of follow-up, 687 incident cases of ESRD were identified in the cohort. The age-adjusted ESRD incidence rate was 273 (per 100,000) among blacks, 3.5-fold higher than the rate of 78 among whites. Risk factors for ESRD included male sex (HR = 1.6; 95% CI 1.4-1.9), low income (HR = 1.5; 95% CI 1.2-1.8 for income below vs. above $15,000), smoking (HR = 1.2; 95% CI 1.02-1.4) and histories of diabetes (HRs increasing to 9.4 (95% CI 7.4-11.9) among those with ≥20 years diabetes duration) and hypertension (HR = 2.9; 95% CI 2.3- 3.7). Patterns and magnitudes of association were virtually identical among blacks and whites. After adjustment for these risk factors, blacks continued to have a higher risk for ESRD (HR = 2.4; 95% CI = 1.9-3.0) relative to whites. The black-white disparity in risk of ESRD was attenuated but not eliminated after control for known risk factors in a closely socioeconomically matched cohort. Further research characterizing biomedical factors, including CKD progression, in ESRD occurrence in these two racial groups is needed. [ABSTRACT FROM AUTHOR]

In recent pooled analyses among whites and Asians, mortality was shown to rise markedly with increasing body mass index (BMI; weight (kg)/height (m)2), but much less is known about this association among blacks. This study prospectively examined all-cause mortality in relation to BMI among 22,014 black males, 9,343 white males, 30,810 black females, and 14,447 white females, aged 40–79 years, from the Southern Community Cohort Study, an epidemiologic cohort of largely low-income participants in 12 southeastern US states. Participants enrolled in the cohort from 2002 to 2009 and were followed up to 8.9 years. Hazard ratios and 95% confidence intervals for mortality were obtained from sex- and race-stratified Cox proportional hazards models in association with BMI at cohort entry, adjusting for age, education, income, cigarette smoking, and alcohol consumption. Elevated BMI was associated with increased mortality among whites (hazard ratios for BMI >40 vs. 20–24.9 = 1.37 (95% confidence interval (CI): 1.02, 1.84) and 1.47 (95% CI: 1.15, 1.89) for white males and white females, respectively) but not significantly among blacks (hazard ratios = 1.13 (95% CI: 0.89, 1.43) and 0.87 (95% CI: 0.72, 1.04) for black males and black females, respectively). In this large cohort, obesity in mid-to-late adulthood among blacks was not associated with the same excess mortality risk seen among whites. [ABSTRACT FROM PUBLISHER]

Objectives: This study aimed to examine the prevalence, trends, and correlates of practitioner-based complementary and alternative medicine (CAM) services use according to race in a socioeconomically disadvantaged population. Design: Included in this cross-sectional analysis were 50,176 African Americans (AAs) and 19,038 whites enrolled into the Southern Community Cohort Study from March 2002 through September 2009. Logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) of CAM services use associated with participant characteristics. Outcome measures: Outcomes include the prevalence of and trends in use of CAM services during 2002-2009 and correlates of use by race. Results: CAM services use during 2002-2009 was greater among whites (11.7%) than among AAs (8.5%), but no significant temporal trends within the 8-year period were observed. The significant associations were observed for CAM services use with higher educational attainment (OR 1.78, 95% CI: 1.61-1.96 for college versus less than high school), household income (OR 1.61, 95% CI: 1.44-1.81 for ≥$50,000 versus <$15,000), and having a history of a chronic disease (OR 1.34, 95% CI: 1.21-1.47) among both AAs and whites. Significant differences in findings between AAs and whites were seen for age (with a sharp decline in use with older age among AAs but not whites), sex (with the excess of female users more striking among whites), employment (with the unemployed among AAs but not whites more likely to be users), alcohol consumption (with white but not AA drinkers more likely to report CAM services use), and cigarette smoking status (with negative association of use with current smokers more striking among whites). Conclusions: CAM services use is associated with sociodemographic and health-related factors, and racial differences in such use exist. The descriptive findings of this study help supplement the limited information on CAM use among low-income and minority populations in the United States. [ABSTRACT FROM AUTHOR]

Background/Aims: Leptin may be an important link between obesity and many high-burden diseases, including cancer and cardiovascular disease, but leptin levels and correlates in individuals of diverse racial backgrounds have not been well characterized despite racial differences in incidence and mortality patterns for many obesity-related diseases. Methods: In a cross-sectional study of 915 white and 892 black women enrolled in the Southern Community Cohort Study (age 40-79 years, half postmenopausal), serum leptin levels were compared between the race groups and across categories of body mass index (BMI). Potential correlates of leptin were assessed via race-stratified linear regression models. Results: Blacks had higher unadjusted leptin levels than whites (geometric mean 22.4 vs. 19.0 ng/ml; p < 0.0001). Leptin increased with increasing BMI, and racial differences in leptin were most pronounced in women with BMI ≥25. Significant correlates of leptin included BMI, age, alcohol consumption, cigarette smoking, diabetes (both races) and fat consumption (black women only). Leptin remained higher in black women (22.7 vs. 18.8 ng/ml) after adjustment for these factors. Conclusions: Persistent racial differences in leptin concentrations exist after adjustment for BMI and other factors. Leptin assessment may be informative in future studies that investigate racial differences in the development of obesity-related diseases. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The World Health Organization estimates that the number of obese and overweight adults has increased to 1.6 billion, with concomitant increases in comorbidity. While genetic factors for obesity have been extensively studied in Caucasians, fewer studies have investigated genetic determinants of body mass index (BMI; weight (kg)/height (m)2) in African Americans. A total of 38 genes and 1,086 single nucleotide polymorphisms (SNPs) in African Americans (n = 1,173) and 897 SNPs in Caucasians (n = 1,165) were examined in the Southern Community Cohort Study (2002–2009) for associations with BMI and gene × environment interactions. A statistically significant association with BMI survived correction for multiple testing at rs4140535 (β = −0.04, 95% confidence interval: −0.06, −0.02; P = 5.76 × 10−5) in African Americans but not in Caucasians. Gene-environment interactions were observed with cigarette smoking and a SNP in ADIPOR1 in African Americans, as well as between a different SNP in ADIPOR1 and physical activity in Caucasians. A SNP in PPARGC1A interacted with alcohol consumption in African Americans, and a different SNP in PPARGC1A was nominally associated in Caucasians. A SNP in CYP19A1 interacted with dietary energy intake in African Americans, and another SNP in CYP191A had an independent association with BMI in Caucasians. [ABSTRACT FROM AUTHOR]

Objectives: To examine the relationship between smoking and weight status in adult women and whether this association differed by race. Methods: The study sample consisted of 22,949 African American and 7831 white women enrolled in the Southern Community Cohort Study from 2002 to 2006. Results: Both African American and white current smokers had decreased odds of being overweight or obese compared to normal-weight nonsmokers, and the inverse trends between current smoking and BMI held for both groups. Conclusion: A strong relationship exists between smoking and weight status, with patterns nearly identical for African Americans and white women. [ABSTRACT FROM AUTHOR]