The effect of heavy prenatal alcohol exposure on adolescent body mass index and waist-to-height ratio at 12-13 years

Abstract

BACKGROUND: Growing evidence suggests that prenatal alcohol exposure (PAE) has the potential to impact on a wide range of physical outcomes in offspring, including metabolism and body composition, although the evidence to-date is primarily from preclinical studies. The current clinical study examined the association between heavy PAE and indirect measures of adiposity in adolescence. METHODS: Analyses drew on data from the Longitudinal Study of Australian Children, a national prospective cohort of children and their families from birth to adolescence. Participants included children with heavy PAE (≥70 g/week; n = 46), measured via maternal self-report of alcohol use during pregnancy and a comparison group of children without any PAE (n = 782), frequency matched on sex, ethnicity and socio-economic position. Body mass index (BMI) z-scores, waist-to-height ratios and proportion overweight/obese were calculated from height, weight and waist circumference measured at age 12–13 years. Two (PAE) × two (sex) ANCOVA and logistic regression models were performed, controlling for matching variables, adolescent age, pubertal status and birthweight; maternal age at birth and smoking during pregnancy. RESULTS: Female adolescents with heavy PAE during late pregnancy had significantly higher BMI z-scores (M = 0.75, SD = 0.69) and proportion overweight/obese (38.5%) than females not exposed to any prenatal alcohol (M = 0.29, SD = 1.07, P = 0.04; 23.8%, P = 0.03, respectively). There was no significant effect of heavy PAE on male adolescent BMI z-scores and proportion overweight/ obese or adolescent waist-to-height ratios (all P > 0.05). CONCLUSIONS: Heavy PAE had a sex-specific effect on measures of adiposity in early adolescence, with girls more likely to have increased BMI and overweight/obesity status. Further longitudinal follow-up of children exposed to PAE is required to confirm if maternal alcohol consumption is a risk factor for later life obesity.