Association between metabolic syndrome and incident fractures in Korean men: a 3-year follow-up observational study using national health insurance claims data.

Context: Although the prevalence of both metabolic syndrome (MetS) and fractures increases with advancing age, studies on possible associations between these conditions in men are limited and the results are inconsistent.

Objective: The objective of the study was to clarify the impact of MetS on the male risk of incident fractures.

Design And Setting: This was a large, longitudinal study with an average 3-year follow-up period.

Participants: Korean men (n = 16 078) aged 50 years or older who had undergone comprehensive routine health examinations participated in the study.

Main Outcome Measures: Incident fractures found after baseline examinations were identified using selected International Classification of Diseases, tenth revision, codes in the nationwide claims database of the Health Insurance Review and Assessment Service of Korea.

Results: In total, 158 men (1.0%) developed incident fractures. The fracture event rates for subjects with and without MetS were 26.2 and 35.7 per 10 000 person-years, respectively. After adjustment for potential confounders, subjects with MetS had a much lower risk of incident fractures than subjects without MetS (hazard ratio 0.662, 95% confidence interval 0.445-0.986). Furthermore, subjects with three and four or more MetS components had a 49.4% and 50.4% lower risk, respectively, of incident fractures compared with the subjects without any MetS components. Importantly, additional adjustment for body mass index eliminated the statistical significance of these associations.

Conclusion: Our current results indicate that the beneficial effects of MetS in reducing fracture risk could be explained by the general obesity that accompanies MetS, although other related factors, such as greater padding effect, peripheral aromatization, or adipokine changes, may also contribute.