Low-density lipoprotein sub-fraction profiles in obese children before and after attending a residential weight loss intervention

Aim: Small dense LDL particles are associated with an increased risk of coronary heart disease and are prevalent in obesity related dyslipidaemia. This study evaluated the effect of weight loss in nine children (BMI 33.4 ± 8.4 kg.m^-2 and age 15.1 ± 2.9 years) on LDL peak particle size, and cholesterol concentrations within particular LDL sub-fractions. Methods: Each child undertook fun based physical activity, dietary restriction and modification and lifestyle education classes in a residential summer weight loss intervention. Blood was drawn before and after intervention and LDL heterogeneity measured by ultracentrifugation. Results: The mean change in body weight were - 6.8 ± 4.9 kg, BMI units - 2.5 ± 1.4 kg.m^-2, and waist circumference - 63 ± 6.3 cm (all p < 0.01). Absolute LDL-c concentration reduced from 106.2 mg/dL to 88.3 mg/dL (p < 0.01). The cholesterol contained within the small dense LDL sub-fraction (LDL-c III) reduced from 54.1 mg/ dL to 40.4 mg/dL (p < 0.01). Peak particle density decreased from 1.041g/mL to 1.035g/mL (p < 0.01). At pre intervention 50.9% of absolute cholesterol was within LDL-c III particles, changing to 46.2%. Conclusion: Mean weight loss of - 6.8 ± 4.9 kg lowers absolute LDL-c and the cholesterol specifically within LDL-c III particles. LDL peak particle size increased and a degree of LDL particle remodelling occurred. These favourable adaptations, accrued in a matter of 4 weeks, maybe associated with a reduction in CHD risk.