Abstract P259: Social and Biological Correlates of Elevated Blood Pressure in Afro-Caribbean Youth: Effect of Individual Risk Factors and Risk Factor Clustering

Abstract

Background: We aimed to estimate the relative risk for elevated blood pressure (BP ≥ 120/80 mmHg) for cardiovascular disease (CVD) risk factors among Afro-Caribbean youth in Jamaica and to evaluate the association between clustering of risk factors and elevated BP. Methods: We analysed data from 898 young adults, 18-20 years old (409 males; 489 females) from the Jamaica 1986 Birth Cohort Study. BP was measured with a mercury sphygmomanometer after the participant had been seated for 5 minutes. Anthropometric measurements were done and venous blood obtained to measure fasting glucose, lipids and insulin. Data on socioeconomic status (SES) were obtained via questionnaire. CVD risk factor status was defined using standard cut-points or the upper quintile of the distribution. Insulin resistance was estimated using the Homeostasis Model Assessment (HOMA-IR). Relative risks were computed using odds ratios (OR) from logistic regression models. Results: Prevalence of elevated BP was 30% among males and 13% among females (p<0.001). In multivariable logistic regression models, modifiable risk factors independently associated with elevated BP among males were: central obesity (OR 4.7, 95%CI 1.6 - 13.7), high glucose (OR 1.9, CI 1.1 - 3.1) and high HOMA-IR (OR 2.33, CI 1.1 - 5.1); among females associated factors were: high triglycerides (OR 2.2, CI 1.1 - 4.1), high HOMA-IR (OR 2.4, CI 1.1 - 5.0) and SES (OR 3.6, CI 1.03 - 12.8 [moderate vs high household possessions]; OR 1.87 CI 0.5 - 7.2 [low vs high]). Among males, having any one of central obesity, high glucose, high triglycerides or high HOMA-IR was associated with a two-fold increase in the odds of elevated BP, while having three or four factors was associated with a seven-fold increase in the odds. Among females, having any one of the four factors above was associated with two-fold higher odds, while having three or four factors was associated with a three-fold higher odds. Conclusion: Factors associated with elevated BP among Jamaican young adults include measures of obesity and insulin resistance, with significant differences by sex. Lower SES was associated with elevated BP among females. Clustering of risk factors was associated with markedly higher odds of elevated BP among males, but less so among females.