Ethnic Differences in the Association between Body Mass Index and Hypertension

Interest in ethnicity-specific definitions of obesity has been hindered by a lack of data clarifying whether or not obesity-related comorbid conditions occur at different levels of body mass index (BMI) (weight (kg)/height (m)2) in different ethnic groups. The objective of this study was to examine ethnic differences in the strength of the association between BMI and hypertension. Cross-sectional data obtained from adults aged 30–65 years in China (1997, n = 3,423), the Philippines (1998, n = 1,929), and the United States (1988–1994, n = 7,957) were used. Higher BMI was associated with a higher prevalence of hypertension in all ethnic groups. However, at BMI levels less than 25, prevalence difference figures suggested a stronger association between BMI and hypertension in Chinese men and women but not in Filipino women, compared with non-Hispanic Whites. NonHispanic Blacks and Filipino women had a higher prevalence of hypertension at every level of BMI compared with nonHispanic Whites and Mexican Americans. These ethnic differences in the strength of association between BMI and hypertension and in underlying prevalence warrant further investigation into the use of ethnicity-specific BMI cutoffs in clinical settings to more accurately identify individuals at risk from obesity.