Abstract P291: Effects of a Multidisciplinary Lifestyle Intervention on HDL Cholesterol Efflux Capacities in Adolescents With Obesity

Abstract

Studies have suggested that a reduced HDL cholesterol efflux capacities (CECs) may be associated with an increased risk of coronary heart disease. However, only few studies have evaluated the impact of a lifestyle modification program on HDL-CEC in adolescents with obesity. The objective of this study was to determine if a 16-week lifestyle modification program would improve HDL-CECs in adolescents with obesity. Twenty-nine adolescents with obesity (16 boys and 13 girls) from 11 to 16 years of age (14.0 ± 1.6 years) were selected to participate in this study. The aim of the lifestyle modification program was to improve eating habits and physical activity levels. During the study, each adolescent was followed by a multidisciplinary team and trained three sessions per week for 16 weeks. The exercise program focused on endurance type activities and all training sessions were supervised and performed in groups. Anthropometric data, metabolic variables and HDL-CECs were measured at baseline and at the end of the intervention. HDL-CECs were measured using ( 3 H)cholesterol-labeled J774 macrophages and HepG2 hepatocytes. Body mass index (33.6 to 32.7 kg/m 2 , p<0.0001) and waist circumference (102.4 to 100.5 cm, p=0.001) were significantly reduced after the 16-week intervention program. We also found a significant decrease in triglyceride concentrations (1.28 to 1.04 mmol/L, p=0.02) as well as in total cholesterol/HDL cholesterol ratio (4.42 to 3.91, p=0.0007) whereas HDL cholesterol levels increased (1.03 to 1.14 mmol/L, p=0.002). J774-HDL-CECs and HepG2-HDL-CECs were not significantly modified after the intervention. In order to further explore the impact of intervention-induced changes in HDL cholesterol levels on exercise-induced changes in HDL-CECs, adolescents were divided into two groups according to their changes in HDL cholesterol levels during the study (low or high intervention-induced changes in HDL cholesterol levels). Adolescents with low HDL cholesterol levels intervention-induced changes did not show an increased in HepG2-HDL-CECs. However, a significant improvement in HepG2-HDL-CEC after the intervention was observed among adolescents characterized by the highest intervention-induced changes in HDL cholesterol levels (p=0.03). Intervention-induced changes in HDL cholesterol levels were also significantly associated with changes in HepG2-HDL-CEC (r=0.55; p=0.002). No association was found between changes in HDL cholesterol levels and changes in J774-HDL-CECs. In conclusion, we found that a structured lifestyle modification program leads to significant improvements in cardiometabolic risk profile and in HepG2-HDL-CEC in obese adolescents.