OBESITY AND HYPERTENSION PREVALENCE IN POPULATIONS OF AFRICAN ORIGIN

Obesity has been shown to be associated with hypertension in Africa, t he Caribbean, and the United States, but there has not: previously bee n an opportunity to compare the magnitude of this relation and estimat e the contribution of obesity to hypertension risk across these popula tions. The International Collaborative Study on Hypertension in Blacks (ICSHIB) used age-stratified sampling and a standardized protocol to measure blood pressure and hypertension risk factors. We analyzed data on 9,102 men and women, age 25-74 years, from seven sites. We studied hypertension (140/90 mmHg or medication) in relation to body mass ind ex (BMI) and sex-specific BMI cutpoints designating ''overweight'' and ''obesity.'' The prevalence of these conditions ranged from 6% to 63% for overweight, from 1% to 36% for obesity, and from 12% to 35% for h ypertension. Adjusted relative risks were similar in most sites, rangi ng from 1.3 to 2.3 for both cutpoints. We found that 6-29% of hyperten sion in each population was attributable to overweight and 0-16% to ob esity. Comparing rural Africa with the United States, 43% of the diffe rence in hypertension prevalence for women was attributable to overwei ght, and 22% for men, whereas respective values for obesity were 14% a nd 11%. These results indicate that the association between adiposity and hypertension is roughly constant across a range of environments, w ith little evidence for variation in susceptibility to effects of over weight in these groups.