Associated Changes In Body Weight, Fat Distribution, And Physical Fitness With Chronic Disease Risk In Adolescents

Abstract

Body weights (BW) in the U.S. have increased over the past two decades. 35%of Hispanic and African American, and 20%of Caucasian children are overweight. Studies have evaluated the relationship between obesity, fat distribution, and risk of chronic disease in adults, but few studies have examined these issues in at risk (particularly Hispanic) youth. PURPOSE To determine if change in BW, adiposity, body fat distribution, and physical fitness over two years are related to change in type 2 diabetes risk and cardiovascular disease (CVD) risk in adolescents. METHODS Subjects were 26 male and 57 female high school students (13–18 yrs) (74%Hispanic, 21%Caucasian). Most were overweight (29.1% ± 9.9% body fat). Body composition by BIA, waist circumference (WC), one mile walk-run test (WR), fasting glucose and insulin (for Type 2 diabetes risk), and fasting total cholesterol, HDL, and triglycerides (for CVD risk) were measured at the schools. T-tests were used to test differences in change from baseline in the variables. Pearson correlations, controlling for school, gender and race, were used to test the relationships between the independent variables and the dependent variables of disease risk change (change in glucose, insulin, cholesterol, triglyceride, HDL). Significance set at p<0.05. RESULTS BW (p<0.001), WC (p<0.001), BMI (p<0.001), and fasting glucose (p<0.01) increased, and fitness (WR) decreased (p<0.05) over 2 yrs. BW change was positively related with change in insulin (.276, p = 0.025), total cholesterol (.373, p = 0.002), and triglycerides (.468, p<0.01). There was a negative trend between change in BW and change in HDL (p = 0.071). Change in WC was positively related to change in total cholesterol (.302, p = 0.015), and triglycerides (.247, p = 0.047) over the two years. Change in BMI was associated with increases in insulin (.264, p = 0.032), total cholesterol (.369, p = .002), and triglycerides (.416, p = 0.001). Change in fitness, as assessed by WR, was not significantly related to change in any chronic disease risk factors. CONCLUSIONS The results of this study indicate that BMI, WC, and BW change over a two-year period are good predictors of a concurrent change in disease risk, and that change in chronic disease risk is apparent as early as adolescence. It is imperative that public health professionals address the issue of increasing adiposity during youth before we develop a generation of individuals who have to live with lifestyle-related chronic disease beginning early in life. Supported by NIH R01 DK48159, NIH M01RR00051 and NIH M01RR00069.