Exercise, lipids, and obesity in adolescents with parental history of coronary disease

Purpose. The purpose of this study is to determine 1) if adolescents of parents with clinically manifest premature coronary artery disease (CAD) are less physically fit and habitually active, and have less favorable lipid profiles and more obesity than children of nonaffected parents, and 2) if aerobic fitness and activity are related to obesity and lipids in adolescents. Setting. Patients were identified in the Coronary Care Unit or out-patient clinic. Adolescents were evaluated in the cardiovascular laboratories at the Francis Scott Key Medical Center. Design. Comparisons between groups were tested with ANOVA. Univariate and multivariate regression were used to assess relationships among study variables. Subjects. Thirty-six children of affected parents, ages 12 to 19 years, and 29 comparison subjects participated in the study. Measures. Fitness was determined by treadmill testing, fasting blood was analyzed for lipoprotein lipids, habitual physical activity was measured by self-report, and the sum of six skinfolds was used to calculate obesity. Results. Total and LDL cholesterol were higher in girls with a parental history of CAD. The sample size was too small to draw any definitive conclusions about differences based on parental history in lipids or fitness in the boys, or obesity in both genders. Overall, joggers were more fit and less fat than nonjoggers. Girls playing organized sports were more fit and less fat than nonparticipants. Aerobic fitness correlated negatively with obesity in both genders; fitness was independently associated with HDL cholesterol only in the boys. Conclusion. The relationships among parental history of premature coronary heart disease, exercise, lipids, and obesity may be gender-specific.