Anthropometric and metabolic characteristics in children with clinically diagnosed nonalcoholic fatty liver disease.
BACKGROUND
Childhood obesity is currently approaching epidemic proportions worldwide. Various chronic diseases are associated with obesity, but nonalcoholic fatty liver disease (NAFLD) has received little attention from paediatricians.


OBJECTIVE
To examine anthropometric and metabolic variables relevant to NAFLD disease mechanism and severity.


METHODS
A retrospective review of 53 consecutive paediatric patients clinically diagnosed with NAFLD was performed between 1997 and 2004. Variables studied included ethnicity, body mass index, acanthosis nigricans, aspartate aminotransferase and alanine amino-transferase levels, and fasting levels of glucose, insulin and lipids. Insulin resistance was quantified by validated models (the homeostasis model of insulin resistance [HOMA-IR] and the quantitative insulin-sensitivity check index [QUICKI]).


RESULTS
The cohort was comprised of 34 boys and 19 girls; there was a 2:1 male predominance. The mean age of the children was 13.5 years (median 14.2 years; range 5.6 to 18.9 years), and 13 were 11 years of age or younger. Forty-five per cent were Caucasian, 30% Asian and 21% Hispanic. Thirty-eight children (72%) were classified as obese and 11 children (21%) were classified as overweight, with a mean ideal body weight percentage of 150.9+/-4.2 (range 67% to 226%) and a BMI Z score of 1.9+/-0.1 (range -1.2 to 3.2). Hyperinsulinemia was present in 35 children (66%). Insulin resistance (HOMA-IR 9.8+/-2.6, abnormal if greater than 3) was associated with increased plasma triglyceride (P=0.03) and total cholesterol (P=0.04) levels. These parameters were significant irrespective of alanine aminotransferase or aspartate aminotransferase levels.


CONCLUSIONS
Hyperlipidemia with hyperinsulinemia and insulin resistance in overweight and obese children with fatty liver may be important signs of liver dysfunction in childhood NAFLD, irrespective of serum aminotransferases. In overweight or obese children with hyperlipidemia or insulin resistance, evaluation for NAFLD is warranted.
Mager
Diana R
DR
Division of Gastroenterology, Hepatology and Nutrition.
Ling
Simon
S
Roberts
Eve A
EA