Clinical

Cardiovascular risk factors, fatty liver disease worsen during puberty in obese kids

Last Updated: 2009-08-07 16:00:05 -0400 (Reuters Health)

By Michelle Rizzo

NEW YORK (Reuters Health) - Cardiovascular risk factors tend to worsen at the onset of puberty and improve in late puberty in untreated obese children and adolescents, recent findings suggest.

"The increasing prevalence of obesity in childhood and adolescence poses an overwhelming problem," Dr. Thomas Reinehr, of Witten/Herdecke University in Datteln, Germany, and Dr. Andre Michael Toschke from King's College London, England, write in the August issue of the Archives of Pediatrics and Adolescent Medicine.

"In addition," they continue, "cardiovascular risk factors and comorbidities such as hypertension, dyslipidemia, disturbed glucose metabolism, and non-alcoholic fatty liver disease are commonly present in obese children and adolescents."

The researchers prospectively examined the course of obesity-related non-alcoholic fatty liver disease and cardiovascular risk factors in 287 untreated obese children and adolescents. The children were examined at baseline and 1 year later.

Roughly half of the cohort was female, mean age was 11.4 years, and mean body mass index was 28.2 kg/m squared. Examination revealed that 20.6% had hypertension, 22.3% had dyslipidemia, 4.9% had impaired fasting glucose, and 29.3% had non-alcoholic fatty liver disease. None was diagnosed with diabetes.

Weight status and the proportion of children with hypertension, hyperglycemia, low HDL-cholesterol levels, or high triglyceride levels remained stable at the 1-year follow-up among those whose pubertal stage had not advanced.

However, in 62 children entering puberty, the team observed increases in prevalence of hypertension (16.1%), hypertriglyceridemia (9.7%), and impaired fasting glucose level (8.1%). Mean HOMA-IR value - a measure of insulin sensitivity -- also increased in these patients (0.42 units).

In 50 children entering late puberty, the team found decreases in hypertension (-18.8%), hypertriglyceridemia (-12.5%), impaired fasting glucose level (-6.3%), and non-alcoholic fatty liver disease prevalence (-18.8%). Mean HOMA-IR values also decreased (-0.83 units). Changes in HOMA-IR values were weakly correlated with changes in cardiovascular risk factors and transaminase levels.

"Cardiovascular risk factors deteriorated with the onset of puberty in obese children and improved at the end of puberty," Dr. Reinehr told Reuters Health in an interview. "Therefore, pubertal obese children have an increased risk for impaired glucose metabolism, dyslipidemia, and atrial hypertension," he said. "The effects of intervention in obese children have to be adjusted for the pubertal development."

Arch Pediatr Adolesc Med 2009;163:709-715.