Anticonvulsant use and fracture: A case-control study

Objectives: We aimed to investigate fracture risk associated with anticonvulsant use in a population-based sample of men and women. Methods: Data from 1,458 participants (51.8% women) with a radiologically confirmed incident fracture (cases) were compared to 1,796 participants (46.5% women) without fracture (controls). Lifestyle factors, medication use and medical history were self-reported. Associations between anticonvulsant use and fracture were explored using binary logistic regression following adjustment for confounders. Results: In men, fracture cases and controls differed in age, smoking history, education, alcohol use, and gonadal hormone supplementation. In women, fracture cases and controls differed by previous fracture history, alcohol use, physical activity levels and use of anti-fracture agents. After adjustment for age, pooled anticonvulsant use was associated with a 3.4-fold higher risk of fracture in men and a 1.8-fold higher risk in women. Following further adjustments for confounders these patterns persisted; a 2.8-fold higher fracture risk in men and a 1.8-fold higher fracture risk in women. Conclusions: Anticonvulsant use was associated with increased fracture risk, independent of demographic, lifestyle, medical and medication related factors. While further studies exploring potential underlying mechanisms are warranted, regular monitoring of bone health in anticonvulsant users with risk factors may be useful.