Risk of fragility fracture among patients with sarcoidosis: a population-based study 1976–2013

Summary: Incidence of fragility fracture of a population-based cohort of 345 patients with sarcoidosis was compared with age and sex-matched comparators. The incidence of fragility fracture was higher among patients with sarcoidosis with hazard ratio (HR) of 2.18. Introduction: Several chronic inflammatory disorders increase the risk of fragility fracture. However, little is known about the risk of fragility fracture in patients with sarcoidosis. Methods: This study was conducted using a previously identified population-based cohort of 345 patients with incident sarcoidosis from Olmsted County, Minnesota. Diagnosis of sarcoidosis required physician diagnosis supported by biopsy showing non-caseating granuloma, radiographic evidence of intrathoracic sarcoidosis, and compatible clinical presentations without evidence of other granulomatous diseases. Sex and age-matched subjects randomly selected from the same underlying population were used as comparators. Medical records of cases and comparators were reviewed for baseline characteristics and incident fragility fracture. Results: Fragility fractures were observed in 34 patients with sarcoidosis, corresponding to a cumulative incidence of 5.6% at 10 years, while 18 fragility fractures were observed among comparators for a cumulative incidence of 2.4% at 10 years. The HR of fragility fractures among cases compared with comparators was 2.18 (95% confidence interval [CI], 1.23–3.88). The risk of fragility fracture by site was significantly higher among patients with sarcoidosis, and was due to a higher rate of distal forearm fracture (HR 3.58; 95% CI 1.53–8.40). Statistically non-significant increased risk was also observed in proximal femur (HR 1.66; 95% CI 0.45–6.06) and proximal humerus (HR 3.27; 95% CI 0.66–16.21). Risk of vertebral fracture was not increased (HR 1.00; 95% CI 0.32–3.11). Conclusion: Patients with sarcoidosis have an increased risk of fragility fracture which is primarily driven by the higher incidence of distal forearm fracture.