Proton Pump Inhibitors and Histamine-2 Receptor Antagonists Are Associated With Hip Fractures Among At-Risk Patients

Abstract

BACKGROUND & AIMS Drugs that inhibit gastric acid might increase the risk of hip fracture. However, little long-term exposure data exist and no large studies have been conducted in the United States. METHODS We conducted a case-control study using data from an integrated health services organization. We evaluated 33,752 patients with incident diagnoses of hip/femur fractures (cases), 130,471 matched members without fractures (controls), prescription data for use of proton pump inhibitors (PPIs) or histamine-2 receptor antagonists (H2RAs) (up to 10 years cumulative duration), and confounders. RESULTS Patients with hip fractures were more likely than controls to have previously received ≥2 years supply of PPIs (odds ratio [OR]=1.30, 95% confidence interval [CI]=1.21–1.39) or H2RAs (OR=1.18, 95% CI=1.08–1.29). The risk was reduced after medication discontinuation (OR=1.30, 95% CI 1.21–1.41 for current PPI users vs. OR=1.09, 95% CI 0.64–1.85 for patients who received their last prescription was 3–5 years ago). Higher dosages (but not increasing cumulative durations) were associated with increased risk (e.g. ≥1.5 pills/day OR=1.41, 95% CI 1.21–1.64; <0.74 pills/day OR=1.12, 95% CI 0.94–1.33). Excess fracture risk for PPI use was only present among persons with at least one other fracture risk factor. CONCLUSION Use of drugs that inhibit gastric acid is associated with an increased risk of hip fracture; however, this association was only found among persons with at least one other risk factor for hip fracture. Acid inhibition might therefore be associated with fracture risk in persons already at risk for osteoporosis, although other confounding cannot be excluded.