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Background: African American men (AA) exhibit a disproportionate share of prostate cancer (PRCA) incidence, morbidity, and mortality. Several genetic association studies have implicated select 8q24 loci in PRCA risk in AA. The objective of this investigation is to evaluate the association between previously reported 8q24 risk alleles and PRCA in African-Barbadian (AB) men known to have high rates of PRCA., Methods: Ten previously reported candidate tag SNPs were genotyped and/or imputed in the 8q24 region in 532 AB men with PRCA and 513 AB controls from the Prostate Cancer in a Black Population (PCBP) study., Results: Rs2124036 was significant in AB men, (OR = 2.7, 95% CI (1.3-5.3), P = 0.005, Empirical (max (T), corrected for multiple testing) P = 0.03) for the homozygous C/C genotype. Only a single SNP from this region remained statistically significant in our analysis of our AB population. These results may indicate the presence of a founder effect or due to the chosen SNPs not tagging an ancestral haplotype bearing the 8q24 risk allele(s) in this population or could reflect inadequate power to detect an association. We conducted a meta-analysis including our AB population along with two additional African Caribbean populations from Tobago and Jamaica for SNPs rs16901979 and rs1447295. Meta-analysis results were most significant for rs16901979 A allele (Z score 2.73; P = 0.006) with a summary OR = 1.31 (95% CI: 1.09-1.58)., Conclusions: Additional studies are needed to provide deeper genotype coverage to further interrogate the 8q24 region to understand its contribution to PRCA in this population., (© 2014 Wiley Periodicals, Inc.)

We describe breast cancer incidence and mortality in the predominantly African-origin population of Barbados, which shares an ancestral origin with African-Americans. Age-standardized incidence rates were calculated from histologically confirmed breast cancer cases identified during a 45-month period (July 2002-March 2006). Mortality rates were estimated from death registrations over 10-years starting January 1995. There were 396 incident cases of breast cancer for an incidence rate of 78.1 (95% confidence interval (CI) 70.5-86.3), standardized to the US population. Breast cancer incidence in African-Americans between 2000 and 2004 was 143.7 (142.0-145.5) per 100,000. Incidence peaked at 226.6 (174.5-289.4) per 100,000 among Barbadian women aged 50-54 years, and declined thereafter, a pattern in marked contrast to trends in African-American women, whose rates continued to increase to a peak of 483.5 per 100,000 in those aged 75-79 years. Incidence rate ratios comparing Barbadian and African-American women showed no statistically significant differences among women aged>or=55 years (p

Throughout biomedical research, there is growing interest in the use of ancestry informative markers (AIMs) to deconstruct racial categories into useful variables. Studies on recently admixed populations have shown significant population substructure due to differences in individual ancestry; however, few studies have examined Caribbean populations. Here we used a panel of 28 AIMs to examine the genetic ancestry of 298 individuals of African descent from the Caribbean islands of Jamaica, St. Thomas and Barbados. Differences in global admixture were observed, with Barbados having the highest level of West African ancestry (89.6%+/- 2.0) and the lowest levels of European (10.2%+/- 2.2) and Native American ancestry (0.2%+/- 2.0), while Jamaica possessed the highest levels of European (12.4%+/- 3.5) and Native American ancestry (3.2%+/- 3.1). St. Thomas, USVI had ancestry levels quite similar to African Americans in continental U.S. (86.8%+/- 2.2 West African, 10.6%+/- 2.3 European, and 2.6%+/- 2.1 Native American). Significant substructure was observed in the islands of Jamaica and St. Thomas but not Barbados (K=1), indicating that differences in population substructure exist across these three Caribbean islands. These differences likely stem from diverse colonial and historical experiences, and subsequent evolutionary processes. Most importantly, these differences may have significant ramifications for case-control studies of complex disease in Caribbean populations.

Objective: To evaluate the prevalence, distribution, awareness, treatment and control of hypertension in an Afro-Caribbean population, and their relationship to 4-year survival. DESIGN Population-based prospective cohort study., Setting and Participants: Simple random sample of Barbados-born citizens (4709 persons; 84% participation), with 4-year follow-up., Interventions: None., Main Outcome Measures: Hypertension prevalence, awareness, treatment and control were evaluated at baseline. Four-year cumulative mortality was assessed by the product-limit method and relative risk of mortality by the Cox proportional hazards method., Results: Mean systolic (SBP) and diastolic (DBP) blood pressure were higher among black than white participants. In the black population, age-specific prevalence of hypertension increased from 32.7% in men and 34.0% in women at 40-49 years of age to 63.4% in men and 85.5% in women at ages 80 years and older, with an overall prevalence of 55.4%. Hypertension awareness, treatment and control rates were 62.5, 53.8 and 18.5%, respectively. Compared to DBP 80 mmHg, the presence of a DBP between 80 and 84 mmHg, 100-109 mmHg and > or = 110 mmHg was associated with adjusted death rate ratios of 1.6, 1.7 and 2.0, respectively. Systolic blood pressure was not related to the risk of cardiovascular mortality, after adjustment for age or other potential confounders. Hypertensives were at modestly increased risk of 4-year cardiovascular mortality [RR = 1.4; 95% confidence inteval (CI) (1.0, 2.0)], while treated uncontrolled hypertensives were at increased risk of all cause [RR = 1.4; 95% CI (1.0, 1.9)] and cardiovascular [RR = 1.6; 95% CI (1.1, 2.5)] mortality., Conclusions: High rates of hypertension in this population coexist with conservative levels of treatment and low rates of blood pressure control. In contrast to other reports, elevated SBP was not independently associated with increased risk of cardiovascular mortality. The modest impact of elevated blood pressure might partly explain the comparatively lower hypertension-related mortality rates in populations of Caribbean-origin. Treated uncontrolled hypertensives are at increased risk of early mortality, signaling the need for strict blood pressure control in this group.