Nitrogen-containing bisphosphonates (N-BPs) such as alendronate, which are widely used to treat post-menopausal osteoporosis, are linked with significantly lower risks of pneumonia and of dying from pneumonia.
The study included 4,041 patients with hip fractures who received N-BPs and 11,802 who did not. Over a median follow-up time of 2.7 years, N-BPs were associated with a 24% lower risk of pneumonia compared with no treatment (69 versus 90 cases per 1,000 people per year).
A similar association was observed with pneumonia mortality, with a 35% lower risk associated with N-BPs (23 versus 35 per 1,000 patients per year for the N-BP and non-N-BP groups, respectively).
Results from previous animal studies indicate that N-BP treatment leads to a high concentration of N-BPs in the respiratory tract. “Together with its anti-inflammatory and immune-modulatory properties, this may explain why N-BPs were associated with reduced risk of pneumonia, as revealed in our study,” said senior author Dr Ching-Lung Cheung, of The University of Hong Kong. He added that studying the potential of N-BPs for treating symptoms of COVID-19 may be warranted.
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.
Chor‐Wing Sing, Douglas P Kiel, Richard B Hubbard, Wallis CY Lau, Gloria HY Li, Annie WC Kung, Ian CK Wong, Ching‐Lung Cheung
Journal of Bone and Mineral Research abstract