Studies investigating the impact of age at menarche on glucose metabolism disorder have reached inconsistent conclusions, and a quantitative comprehensive assessment of the dose-response association between age at menarche and glucose metabolism disorder has not been reported. We performed a systematic review and meta-analysis of studies assessing the risk of glucose metabolism disorder by age at menarche.
MEDLINE via PubMed and EMBASE databases were searched up to March 13, 2019. Restricted cubic splines were used to model the dose-response association.
Twenty-five publications (including 34 studies) were included in the meta-analysis. The summary risk ratios (RRs) and 95% confidence limit (CL) per 1-year increase in age at menarche were 0.98 (95% CL 0.98, 0.99) for type 2 diabetes mellitus (T2DM), 0.97 (95% CL 0.96, 0.99) for impaired fasting glucose (IFG), and 0.98 (95% CL 0.97, 0.99) for gestational diabetes mellitus (GDM). We identified linear negative correlations between age at menarche and T2DM (Pnonlinearity = 0.052) and IFG (Pnonlinearity = 0.145), a nonlinear dose-response between age at menarche and GDM (Pnonlinearity = 0.038).
Older age at menarche (range 8-18 years old) is associated with reduced risk of glucose metabolism disorder. The strongest reduction in risk of GDM is observed at menarche age of 14.5 years.