Risk of hip fracture associated with untreated and treated chronic hepatitis B virus infection

Background & Aims Chronic hepatitis B (CHB) infection is associated with reduced bone mineral density, but its association with fractures is unknown. Our objectives were to determine whether untreated or treated CHB-infected persons are at increased risk for hip fracture compared to uninfected persons. Methods We conducted a cohort study among 18,796 untreated CHB-infected, 7777 treated CHB-infected, and 979,751 randomly sampled uninfected persons within the U.S. Medicaid populations of California, Florida, New York, Ohio, and Pennsylvania (1999-2007). CHB infection was defined by two CHB diagnoses recorded >6 months apart and was classified as treated if a diagnosis was recorded and antiviral therapy was dispensed. After propensity score matching of CHB-infected and uninfected persons, Cox regression was used to estimate hazard ratios (HRs) with 95% confidence intervals (CIs) of incident hip fracture in: (1) untreated CHB-infected vs. uninfected, and (2) treated CHB-infected vs. uninfected patients. Results Untreated CHB-infected patients of black race had a higher rate of hip fracture than uninfected black persons (HR, 2.55 [95% CI, 1.42-4.58]). Compared to uninfected persons, relative hazards of hip fracture were increased for untreated white (HR, 1.26 [95% CI, 0.98-1.62]) and Hispanic (HR, 1.36 [95% CI, 0.77-2.40]) CHB-infected patients, and treated black (HR, 3.09 [95% CI, 0.59-16.22]) and white (HR, 1.90 [95% CI, 0.81-4.47]) CHB-infected patients, but these associations were not statistically significant. Conclusions Among U.S. Medicaid enrollees, untreated CHB-infected patients of black race had a higher risk of hip fracture than uninfected black persons.