The Role of Metabolic Syndrome and its Components in Incident Fracture: A 15-Year Follow-Up among the Iranian Population

Abstract

Context: The relationship between metabolic syndrome (MetS) and the risk of fracture is a matter of debate. Objective: This work aimed to determine the impact of MetS and its components on the risk of hospitalized fractures, during a median follow-up of 15.9 years. Methods: A total of 7,520 participants (4,068 women) 30 years or older entered the study. Multivariable Cox proportional hazards regression were applied for data analysis. Results: The prevalence of MetS was 40.0% and 40.4% in men and women, respectively. During the follow-up, hospitalized fracture was observed in 305 cases (men=152). The multivariable hazard ratio (HR) and 95% confidence interval (CI) of MetS for incident fracture for men and women was 0.72 (0.49-1.05, P=.08) and 1.38 (0.96-1.98, P=.08), respectively. In the fully adjusted model, high fasting plasma glucose (FPG) among men tended to be associated with a lower risk of fracture [0.67 (0.44-1.02, P=.06)]; among women, high waist circumference (WC) was associated with a greater risk [2.40 (1.55-3.73)]. Among the population 50 years and older in the pooled sample, MetS was not accompanied by the risk of fracture, but high WC was associated with a higher risk [1.58 (1.07-2.33)]. For incident hip/pelvic fracture, abdominal obesity - but not MetS per se - was also a strong and independent risk factor. Conclusion: A significant sex difference in the association between MetS and its components with incident fracture was observed. Women with central adiposity were at increased risk of hospitalized fracture, whereas men with high FPG were at decreased risk.