Lipid and insulin levels in obese children: Changes with age and puberty

Objective: The goal was to describe the lipid profile and insulin changes seen in obese children and adolescents at different stages of puberty. Research Methods and Procedures: A cross-sectional study was conducted by chart review of 181 obese (BMI > 95th) children and adolescents 5 to 17 years of age, who were referred to the Center for Atherosclerosis Prevention for cardiovascular risk reduction from January 2003 through December 2003. Results: Eighty (44.2%) subjects were <12 years of age, and 101 (55.8%) were ≥12 years. Severity of obesity as expressed by BMI standard deviation score did not differ between these age groups. A significant difference with lower serum levels of total cholesterol, non-high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol was seen with older age and with advancing sexual maturity rating. Triglycerides, very-low-density lipoprotein cholesterol, and lipoprotein(a) levels remained elevated across age and pubertal stages. Insulin levels and insulin resistance as expressed by homeostasis model assessment were significantly higher with older age. Similar trends were observed both in obese boys and obese girls during puberty. Discussion: The most striking findings of this study are that in the 5- to 17-year-old obese population, the combination of elevated triglycerides and very-low-density lipoprotein cholesterol and low high-density lipoprotein cholesterol levels place them at greater cardiovascular risk than their non-obese peers, even when the changing patterns of lipids and lipoproteins seen during pubertal maturation are accounted for.