Overall and central obesity and risk of type 2 diabetes in U.S. black women.
OBJECTIVE
Obesity has risen to epidemic proportions in the United States, leading to an emerging epidemic of type 2 diabetes. African-American women are disproportionately affected by both conditions. While an association of overall obesity with increasing risk of diabetes has been documented in black women, the effect of fat distribution, specifically abdominal obesity, has not been studied. We examined the association of BMI, abdominal obesity, and weight gain with risk of type 2 diabetes.


METHODS
During eight years of follow-up of 49,766 women from the Black Women's Health Study, 2472 incident cases of diabetes occurred. Cox proportional hazard models were used to estimate incidence rate ratios (IRRs), with control for age, physical activity, family history of diabetes, cigarette smoking, years of education, and time period of data collection.


RESULTS
Sixty-one percent of participants had a BMI>or=25 kg/m2 (WHO definition of overweight). Compared with a BMI of <23 kg/m2, the IRR for a BMI of >45 kg/m2 was 23 (95% confidence interval, 17.0 to 31.0). The IRR for the highest quintile of waist-to-hip ratio relative to the lowest was 2.3 (95% confidence interval, 2.0 to 2.7) after control for BMI. Furthermore, at every level of BMI, an increased risk was observed for high waist-to-hip ratio relative to low.


CONCLUSIONS
Central obesity, as well as overall obesity, is a strong risk factor for diabetes in African-American women. Efforts to reduce the prevalence of obesity in African-American women are of paramount importance.
Krishnan
Supriya
S
Slone Epidemiology Center, 1010, Commonwealth Avenue, Fourth Floor, Boston, MA 02215, USA. skrishnan@slone.bu.edu
Rosenberg
Lynn
L
Djoussé
Luc
L
Cupples
L Adrienne
LA
Palmer
Julie R
JR
D000328:Adult; D000368:Aged; D044383:Black People / Q000706:statistics & numerical data*; D015992:Body Mass Index; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D009765:Obesity / Q000150:complications* / Q000453:epidemiology*; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014481:United States / Q000453:epidemiology; D001741:Black or African American