Americans of South Asian descent are twice as likely as whites to have risks for heart disease, stroke and diabetes, when their weight is in the normal range, according to a study published in the Annals of Internal Medicine.
Dr. Namratha Kandula, associate professor of Medicine in the Division of General Internal Medicine and Geriatrics, and Dr. Kiang Liu, professor of Preventive Medicine in the Division of Epidemiology, at Northwestern University Feinberg School of Medicine Program in Public Health, co-authored the study, which was headed by investigators at Emory University Rollins School of Public Health and University of California, San Francisco.
Americans of Hispanic descent were 80 percent more likely than whites to suffer from so-called cardio-metabolic abnormalities that give rise to heart disease, stroke and diabetes, compared with 50 percent more likely for those who were Chinese and African-American.
These risks include high blood pressure (hypertension), elevated glucose, low HDL, the “good cholesterol,” and high triglycerides, a fat found in blood. In the study, participants, who were aged between 45 and 84, were classified as having cardio-metabolic abnormalities if they had two or more of these four risk factors.
“So much of what is known about cardiovascular disease and diabetes risk is from research in white populations, despite the fact that race/ethnic minorities have a high burden of these common diseases,” Dr. Kandula said. “This paper challenges the established idea of using body mass index as the main predictor of cardiovascular and diabetes risk. This matters because most clinicians use BMI cut-points as practical markers for detecting overweight and as a criteria for screening patients for cardiovascular and diabetes risk. Our study suggests that a BMI-based approach may miss a large proportion of individuals who have cardiovascular risk factors and could increase disparities among racial and ethnic minority populations.”
The study included 803 South Asian residents of San Francisco Bay and Chicago areas, who traced their ancestry to India, Pakistan, Nepal, Bangladesh or Sri Lanka. Also enrolled in a parallel study were approximately 6,000 residents of New York, Baltimore, Chicago, Los Angeles, Minneapolis-St. Paul and Winston-Salem areas, who identified as Chinese, white, Hispanic or African-American.
For whites, Hispanics and African-Americans, normal weight was categorized as having a body mass index (BMI) between 18.5 and 24.9 kg/m2. For Chinese and South Asians, the range was narrower: from 18.5 to 22.9 kg/m2.