Nitrogen-Containing Bisphosphonates Are Associated With Reduced Risk of Pneumonia in Patients With Hip Fracture

The objective of this work was to study the risk of pneumonia and pneumonia mortality among patients receiving nitrogen-containing bisphosphonates (N-BPs), non-N-BP anti-osteoporosis medications, and no anti-osteoporosis medications after hip fracture. We studied a historical cohort using a population-wide database. Patients with first hip fracture during 2005–2015 were identified and matched by time-dependent propensity score. The cohort was followed until December 31, 2016, to capture any pneumonia and pneumonia mortality. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox-proportional hazards regression. Absolute risk difference (ARD) and number needed to treat (NNT) were calculated. We identified 54,047 patients with hip fracture. Of these, 4041 patients who received N-BPs and 11,802 without anti-osteoporosis medication were propensity score–matched. N-BPs were associated with a significantly lower risk of pneumonia compared with no treatment (6.9 versus 9.0 per 100 person-years; HR 0.76; 95% CI, 0.70 to 0.83), resulting in an ARD of 0.02 and NNT of 46. A similar association was observed with pneumonia mortality (HR 0.65; 95% CI, 0.56 to 0.75). When N-BPs were compared with non-N-BP anti-osteoporosis medications, the association remained significant. N-BPs were associated with lower risks of pneumonia and pneumonia mortality. Randomized controlled trials are now required to determine whether N-BPs, non–vaccine-based medications, can reduce pneumonia incidence in high risk groups.