Impact of age at menarche on obesity and glycemic control in Japanese patients with type 2 diabetes: Fukuoka Diabetes Registry

AIMS/INTRODUCTION: A younger age at menarche is associated with obesity and type 2 diabetes in adult life. The impact of early‐onset menarche on obesity and glycemic control in type 2 diabetes has not been investigated. The present study examined the relationship between age at menarche and obesity and glycemic control in type 2 diabetes. MATERIALS AND METHODS: A total of 2,133 patients with type 2 diabetes aged ≥20 years were divided into groups according to age at menarche (≤11, 12, 13, 14 and ≥15 years). A retrospective cohort study examined the association of menarcheal age with adiposity and hemoglobin A(1c). RESULTS: Age at menarche was inversely associated with body mass index (BMI) and abdominal circumference (P < 0.001). Each 1‐year decrease in age at menarche was associated with a 0.25‐kg/m(2) and 0.6‐cm increase in BMI and abdominal circumference, respectively, using a multivariate‐adjusted model. Odds ratios for obesity and abdominal obesity significantly increased in participants with age at menarche ≤11 years after multivariable adjustments when age at menarche of 13 years was used as the reference (odds ratio 1.95, 95% CI 1.33–2.88, odds ratio 1.95, 95% CI 1.32–2.87, respectively). Younger age at menarche was significantly associated with higher hemoglobin A(1c) (P < 0.001); however, the association was not statistically significant after adjusting for BMI. CONCLUSIONS: Age at menarche of ≤11 years was associated with obesity after adjusting for confounding factors, and poor glycemic control associated with high BMI in type 2 diabetes. Age at menarche should be considered during clinical assessments.