Risk of fractures and postfracture mortality in 3980 people with primary biliary cholangitis: A population-based cohort study

Abstract

Background: Morbidity in primary biliary cholangitis (PBC) is multifactorial. Osteoporosis related to cholestasis is an extrahepatic complication of PBC. It is not fully established to what extent people with PBC have an increased risk for fractures, and if mortality after a fracture is increased, compared to the general population. Methods: All Swedish people with PBC diagnosed between 2001 and 2016 were identified from the National Swedish Patient Register using ICD-10 codes. Incident fractures were ascertained in the same register and compared to matched controls from the Swedish general population (1:10 for age, sex, and municipality). Cox regression was used to investigate the rates of fractures and postfracture mortality. The cumulative incidence of fractures was calculated while accounting for competing risks (death or liver transplantation). Results: People with PBC (n = 3980) showed a higher risk of fractures at all-time points during follow-up compared to matched controls (n = 37,196), which was seen both in men and women. At 5 years of follow-up, the cumulative incidence of any fracture in people with PBC was 16.8% (95% confidence interval [CI] = 15.6–18.1), compared to 11.6% (95%CI = 11.3–12.0) in controls. The rate of osteoporotic fractures was particularly high (adjusted Hazard ratio [aHR] = 1.9; 95% = CI 1.7–2.0). The 30-day as well as the 1-year mortality after a fracture was significantly higher in people with PBC compared to controls that also experienced a fracture (aHR = 2.2; 95%CI = 1.5–3.2; aHR = 2.0; 95%CI 1.7–2.4). Conclusion: People with PBC have a significantly higher risk of fractures and postfracture mortality compared to matched controls from the general population.