Cardiovascular disease (CVD) and its risk factors are highly prevalent in the UK, with incidence differing by ethnicity. Black individuals have an increased prevalence of heart failure, stroke and hypertension compared to White individuals. Telomere length has been associated with many age-related conditions, with shorter telomeres associated with increased CVD risk. However, Black individuals have longer telomeres on average compared to White individuals, which should be protective against CVDs. The increased incidence of CVD in this population indicates a paradoxical association. To investigate the relationship between telomere length and cardiovascular disease risk across ethnic groups and to identify genetic variants that may explain observed differences. Using the UK Biobank cohort, we assessed telomere length in Black and White populations and performed GWAS analysis to identify ethnicity-specific variants associated with telomere length. We report that Black individuals had significantly longer telomeres than White individuals (0.9035 vs 0.8301, p < 0.0001). Contrary to published reports, Black individuals showed lower incidence of most CVD subtypes compared to White individuals. However, hypertension was more prevalent in Black individuals despite longer telomeres. GWAS analysis identified 12 ethnicity-specific variants at genome-wide significance associated with longer telomeres in Black populations. Notably, 3 variants in SLX4 were significantly more common in Black individuals and associated with both longer telomere length and hypertension risk. High BMI and lower household income were found to influence hypertension risk, overriding the protective effect of longer telomeres in Black populations. The increased rate of hypertension in Black populations, as well as longer telomere length, may be influenced by common genetic variants. The protective effect of longer telomeres against CVD does not extend to hypertension, where socioeconomic and metabolic factors appear to override this protection.
Benfield et al. (Fri,) studied this question.