Legacy of Tehran Lipid and Glucose Study; Evidence on Reproductive Lifespan and Cardiometabolic Health

Abstract

Context: Understanding the different reproductive factors and their link to non-communicable diseases (NCDs) is crucial in a community-based cohort study. The present study provides a comprehensive synthesis of published findings derived from the Tehran lipid and glucose study (TLGS) pertaining to women, offering insights into the epidemiological patterns of reproductive lifespan and its impact on cardiometabolic parameters. Evidence Acquisition: We conducted a thorough review of all studies on reproductive lifespan conducted within the TLGS framework. Results: Overall, the mean (SD) age at menarche among participants was 13.35 (1.5) years, whereas the mean (SD) age at menopause was 50.16 (5.7) years. Early menarche was identified as a significant factor associated with later metabolic impairments, including higher odds of prediabetes (OR: 2.7; 95% CI: 1.1 - 6.6), type 2 diabetes mellitus (DM) (OR: 3.6; 95% CI: 1.2 - 10.7), and metabolic syndrome (MetS) (OR: 2.3; 95% CI: 1.1 - 5.4) in fully adjusted models. Comparisons between surgical and natural menopause revealed that the incidence of MetS was nearly tenfold higher among women who experienced surgical menopause, accompanied by elevated mean fasting plasma glucose (FPG) and 2‑hour post‑load glucose concentrations. Furthermore, each additional year in age at natural menopause was associated with a 10% increase in the incidence of chronic kidney disease (CKD), whereas prolonged exposure to endogenous estrogen appeared to confer protective effects, reducing the incidence of hypertension, cardiovascular disease (CVD), CKD, and osteoporotic fractures. In addition, lactation was found to markedly lower the risk of MetS among women with a prior history of gestational diabetes, emphasizing its potential long‑term cardiometabolic benefits. Conclusions: The reproductive milestones significantly shape women’s long‑term cardiometabolic health, supporting the integration of reproductive history into preventive care models and longitudinal risk assessment frameworks.