Less Cardiac Risk As BMI Nears Morbidly Obese Range
Triglyceride, apolipoprotein B levels increase with adiposity only up to a point, then decline
THURSDAY, Jan. 3 (HealthDay News) -- Some cardiovascular risk factors do not increase with greater degrees of obesity, but instead decline in the morbidly obese, researchers report in the November/December issue of Surgery for Obesity and Related Diseases.
Edward H. Livingston, M.D., of the University of Texas Southwestern Medical Center in Dallas, and colleagues analyzed results of the National Health and Nutrition Examination Survey III database for correlations between obesity and cardiovascular risk factors. Regression and contour mapping techniques were used to further analyze the relationship between anthropomorphic measurements and cardiovascular risk.
While most cardiovascular risk factors -- including systolic blood pressure, serum glucose, hemoglobin A1C, C-reactive protein and fibrinogen -- were positively correlated with increasing body mass index (BMI), massively obese individuals were found to have improvements in some cardiovascular risk factors. Plasma triglyceride concentrations increased up to a BMI of 35 kg/m2 in men and a BMI of 45 kg/m2 in women and then decreased as BMI increased. Similarly, concentrations of apolipoprotein B and serum low-density lipoprotein levels increased with an increasing BMI up to 35 kg/m2 and then decreased as BMI increased.
"The discrepancy is related, in part, to body conformation. The criteria for obesity surgery should be changed to lower BMIs than are currently used if patients have risk factors for cardiovascular disease," the authors conclude.