Development of adiposity, obesity and age at menarche: an 8-year follow-up study in Portuguese schoolgirls

Abstract

AIM: It has been suggested that the decline in menarcheal age is associated with the increase of obesity prevalence. OBJECTIVE: To examine the association between age at menarche and adiposity development from age 7 to 15 years. SUBJECTS: A cohort of 109 schoolgirls from Viana do Castelo (Northern Portugal). METHODS: Anthropometric measurements (height, weight, and triceps and subscapular skinfold thicknesses) were longitudinally obtained at 7, 8, 9, and 15 years. Waist circumference and self-reported age at menarche were obtained at age 15. Obesity was defined by the cut-off value of 30% body fat. Ages of <12 years, 12-13 years, and >13 years were classified as early menarche (EM), average menarche (AM) and late menarche (LM), respectively. RESULTS: Median menarcheal age was 12.0 years (range, 8-15 years), with 26.6% of girls classified as EM. Compared with their LM peers, EM girls were always fatter (p=0.001) and had higher waist circumference at age 15 (p=0.009). All variables showed significant negative associations with age at menarche, except subscapular to triceps skinfold ratio at all ages and height at age 15. At both ages 9 and 15 years, LM girls had the lowest prevalence of obesity (4.5% and 9.1%, respectively). The 8-year incidence of obesity in EM girls was 24.1%, while that in the AM plus LM group was 13.8% (p=0.005). CONCLUSION: EM seems to be a risk factor for the development of obesity during adolescence. However, this vulnerability may start to be programmed before menarche as girls with precocious menarche were already fatter than their late-maturing peers at age 7 years.