Association of age at menarche with cardiovascular risk factors, vascular structure, and function in adulthood: the Cardiovascular Risk in Young Finns study

BACKGROUND: It is unclear whether age at menarche is an independent determinant of future cardiovascular risk. OBJECTIVE: We aimed to determine whether menarcheal age is an independent predictor of body mass index (BMI) and a wide range of cardiovascular risk factors in adolescence and adulthood. DESIGN: We examined the associations of menarcheal age with BMI (in kg/m(2)) and other cardiovascular risk factors in adolescence and adulthood in a population-based sample of 794 female adolescents aged 9-18 y at baseline. Their age at first menstruation was requested at baseline and again 3 and 6 y later. Cardiovascular risk factors were assessed at baseline and at age 30-39 y. RESULTS: A 1-y decrease in menarcheal age was associated with 0.81 (95% CI: 0.53, 1.08) higher adult BMI as well as greater waist circumference and waist-to-hip ratio, elevated systolic blood pressure, higher insulin resistance, and greater risk of metabolic syndrome (P < 0.05 for all). In multivariable analysis in which these adult risk factors were mutually adjusted for, only the inverse association between age at menarche and adult BMI remained. However, this inverse association was lost after adjustment for premenarcheal BMI (beta: -0.16; 95% CI -0.55, 0.23; P = 0.42). Higher premenarcheal BMI predicted earlier menarche, and the strong association between premenarcheal BMI and adult BMI was robust to adjustment for age at menarche. CONCLUSIONS: These findings suggest that early menarche is only a risk marker. Greater childhood BMI seems to contribute to earlier age at menarche and, because of tracking, greater adult BMI and associated cardiovascular risk. An independent effect of early menarche on adult adiposity cannot be excluded, but it is likely to be small at best.