Association of fat and salt intake with blood pressure in urban African-American hypertensive adults

Two-hundred eighteen hypertensive African-American adults in Baltimore city participating in a community based hypertension control study were interviewed at their fourth home visit by their community health worker. Subjects responded to a 12 item fat intake screener (FIS2) [A. Dowdy, et al; in press, AJPH] and to 2 salt intake items: 1) add salt before tasting food and 2} add salt to cooking water. The salt items were summed (score 0-2). Weight and self-reported height were used to compute body mass index (BMI); blood pressure was measured following AHA protocol. Other items included: age, gender, exercise, current use of alcohol, cigarettes, and high blood pressure (HBP) medication, and history of comorbidities. Mean diastolic pressure (DBP) was significantly (p< 0.0001) higher among subjects whose FIS2 score was > = 25 [85.3 (15.8)], the suggested cutpoint for high fat and/or cholesterol intake, than among subjects with scores <25 [76.4 (9.6}]. Systolic pressure (SBP) did not differ by FIS2 score. Likewise, neither SBP nor DBP differed by salt intake score. In separate multiple linear regression models for SBP and DBP, females, BMI < = 30, HBP medication, and lack of exercise were associated with higher systolic pressure, whereas age < 65, fat score > =25, HBP medication, and alcohol use were associated with higher diastolic pressure. Fat intake as measured by the FIS2, but not salt intake, was a significant predictor of diastolic pressure, even accounting for other demographic, lifestyle, and comorbidity risk factors in this study population, suggesting the importance of diet in controlling hypertension in the urban African-American community .