Independent association of waist circumference with hypertension and diabetes in African American women, South Carolina, 2007-2009.

Introduction: Obesity is associated with hypertension and diabetes, which are independent risk factors for cardiovascular disease (CVD); 53% of African American women are obese. Of the approximately 44% of African American women who are hypertensive, more than 87% are overweight or obese. Additionally, more than twice as many African American women (13.1%) as white women (6.1%) have been diagnosed with type 2 diabetes. Obesity is usually measured using body mass index (BMI). However, abdominal adiposity may be more predictive of CVD risk than BMI. This study investigates the independent association of waist circumference with hypertension and diabetes in African American women.

Methods: As part of the Faith, Activity, and Nutrition (FAN) program, we recruited 843 African American women (mean age 53.8 y [SD, 14.1 y]) from African Methodist Episcopal churches. If a participant reported she had hypertension or had measured systolic blood pressure at or higher than 140 mm Hg or measured diastolic blood pressure at or higher than 90 mm Hg, she was classified as having hypertension. To assess increased health risks associated with waist circumference, we used the World Health Organization's standards to categorize waist circumference as normal risk (waist circumference <80 cm), increased risk (waist circumference 80-88 cm), or substantially increased risk (waist circumference >88 cm). We used logistic regression models to test predictors of hypertension and diabetes.

Results: Of 843 study participants, 205 had diabetes and 545 were hypertensive. Women with a waist circumference of 88 cm or more were at increased risk for hypertension (odds ratio [OR] = 7.17, P < .002) and diabetes (OR = 6.99, P < .001). Associations remained after controlling for all variables (hypertension OR = 5.53, P < .001; diabetes, OR = 5.38, P < .001).

Conclusion: After controlling for all variables, waist circumference was independently associated with a 5-fold risk in hypertension and diabetes in African American women.