The COMT val158met polymorphism is associated with prevalent fractures in Swedish men

Introduction Sex steroids are important for growth and maintenance of the skeleton. Catechol-O-methyltransferase (COMT) is an estrogen degrading enzyme. The COMT val158met polymorphism results in a 60–75% difference in enzyme activity between the val (high activity = H) and met (low activity = L) variants. We have previously reported that this polymorphism is associated with bone mineral density (BMD) in young men. The aim of this study was to investigate associations between COMT val158met, BMD and fractures in elderly men. Methods Population-based study of Swedish men 75.4, SD 3.2, years of age. Fractures were reported using standardized questionnaires. Fracture and genotype data were available from 2822 individuals. Results Total number of individuals with self-reported fracture was 989 (35.0%). Prevalence of ≥ 1 fracture was 37.2% in COMTLL, 35.7% in COMTHL and 30.4% in COMTHH (p < 0.05). Early fractures (≤ 50 years of age) were less common in COMTHH than in the combined COMTLL + HL genotype, OR 0.78 (95% CI 0.63–0.97). No associations were found for late fractures (> 50 years of age). The OR for fracture of the non-weight bearing skeleton in COMTHH compared with COMTLL + HL was 0.74 (95% CI 0.59–0.92). No associations between COMT val158met and BMD were found in this cohort of elderly men. Conclusions The COMT val158met polymorphism is associated with life time fracture prevalence in elderly Swedish men. This association is mainly driven by early fractures (≤ 50 years of age).