Sex and Ethnic Differences in the Relationship between Changes in Anthropometric Measurements and Visceral Fat in Adolescents with Obesity

Abstract

To examine sex and ethnic differences in how baseline and changes in anthropometric measures relate with change in visceral fat with interventions in adolescents. Black and white adolescents (n=143: body mass index [BMI] ≥85th percentile, 12-18years) who participated in intervention studies (3-6months) were included and had assessments of anthropometric measures (weight, BMI, waist circumference, waist-to-hip ratio [WHR], and waist-to-thigh ratio) and visceral fat at L4-L5 by magnetic resonance imaging before and after interventions. At baseline, all of the anthropometric measures were positively associated with visceral fat (P<.05), with weight, waist circumference, and WHR having the largest variance explained (model adjusted R2=0.35-0.47 vs 0.32-0.35). Blacks had 11.5-23.3cm2 less visceral fat compared with whites for a given anthropometric value. Girls tended to have less visceral fat for a given anthropometric value, but the sex differences were not consistently significant (range: 0.7-12.9cm2). Changes in waist circumference, BMI, and weight, but not WHR, remained significantly associated with changes in visceral fat. There were no sex differences, and much more minimal ethnic differences (<4.9cm2). At baseline, there are sex and ethnic differences in how anthropometric measures correlate with visceral fat. However, there were minimal sex and ethnic differences in how changes in anthropometric measures related with changes in visceral fat. Although all of the anthropometric measures were associated with visceral fat at baseline, waist circumference, BMI, and weight, but not WHR were associated with changes in visceral fat. Clinicaltrials.gov: NCT00739180, NCT01323088, and NCT01938950.