Duration of reproductive period and metabolic syndrome and its components: findings from the Henan Rural Cohort Study in menopausal women

Abstract Purpose: The purpose of this study was to investigate the relationship of duration of reproductive period with metabolic syndrome (MetS) and its components in rural population. Methods: In all, 14596 menopausal women were enrolled from the Henan Rural Cohort study. Logistic regression and linear regression were used to evaluate the association between duration of reproductive period and MetS and its components (including central obesity, abnormal fasting plasma glucose (FPG), abnormal blood pressure (BP), abnormal triglycerides (TG) and abnormal high-density lipoprotein cholesterol (HDL-C)). In addition, the mediation and interaction effects were performed by mediation analyses and generalized linear model. Results: Each year of increase reproductive period correlated with an increased risk of MetS (OR = 1.031; 95% CI = 1.023-1.039; P < 0.05). This association changed slightly after adjusting for BMI and remained statistically significant (OR (95% CI): 1.012(1.003, 1.021)). A positive association between duration of reproductive period and central obesity, abnormal FPG, abnormal BP, abnormal TG, and abnormal HDL-C were revealed (all P < 0.05). The relationship with abnormal FPG (OR (95% CI): 1.009(1.000, 1.017)) and abnormal TG (OR (95% CI): 1.013(1.005, 1.021)) were attenuated after adjusting for BMI and remained statistically significant except for central obesity, abnormal BP and abnormal HDL-C. In addition, participants with earlier menarche age and later menopause age might have a higher risk of MetS. In addition, BMI partially mediated the relationship between duration of reproductive period and MetS, abnormal FPG, or abnormal TG, and completely mediated the relationship between duration of reproductive years and abnormal BP, or abnormal HDL-C. The significant interaction of high fat diet was found in association between duration of reproductive period and MetS (P interaction = 0.011). Conclusion: The longer duration of reproductive period might raise a woman's risk of MetS and its components. More importantly, the association was largely mediated by BMI. There is an interaction effect between duration of reproductive period and high fat diet on the risk of MetS.