Effect of Pneumonia on All-cause Mortality after Elderly Hip Fracture: a Korean Nationwide Cohort Study.
Level 3 - non-randomized controlled study
Retrospective nationwide cohort study using administrative claims data
PubMed 31920015 · doi:10.3346/jkms.2020.35.e9
What was done
The authors analyzed 14,736 patients older than 65 years who underwent hip fracture surgery between January 2005 and December 2014 from the Korean National Health Insurance Service (NHIS) Senior cohort (a 10% random sample of enrollees > 60 years). They determined the incidence of in-hospital pneumonia during surgical admission and evaluated all-cause mortality from postoperative day 30 to 1 year using multivariable-adjusted Cox proportional hazards models, stratified by age and sex.
What was found
- In-hospital pneumonia occurred in 11.05% of patients (1,629/14,736), with higher incidence in men (16.39%, 601/3,666) than women (9.29%, 1,028/10,042). - Compared to non-pneumonia patients (n = 13,107), pneumonia was associated with significantly higher all-cause mortality across all follow-up windows: 30-day adjusted relative risk (aRR) 2.69 (95% CI, 2.14–3.38; P < 0.001); 90-day aRR 3.40 (95% CI, 3.01–3.83; P < 0.001); 180-day aRR 2.86 (95% CI, 2.61–3.15; P < 0.001); and 1-year aRR 2.31 (95% CI, 2.14–2.50; P < 0.001). - Relative mortality risk in pneumonia patients was highest in younger age brackets: < 70 years (aRR 5.75, 95% CI 2.89–11.43), 70–79 years (aRR 5.14, 95% CI 4.08–6.46), 80–89 years (aRR 3.29, 95% CI 2.81–3.86), and ≥ 90 years (aRR 2.02, 95% CI 1.52–2.69). - Increased mortality was observed in both men (aRR 3.63, 95% CI 3.01–4.38) and women (aRR 3.27, 95% CI 2.80–3.83).
Why it matters
This nationwide study demonstrates that post-operative pneumonia affects over one in ten elderly hip fracture patients and more than doubles their risk of death over the subsequent year. It underscores the critical need for proactive respiratory care and infection prevention during acute hospitalization for geriatric hip fractures.
Limits
The study relies on retrospective administrative claims data, creating potential for diagnostic misclassification of pneumonia without radiographic or clinical verification. The abstract does not detail the exact covariates included in the multivariable adjustments, leaving potential for residual confounding by baseline functional status or frailty. The cohort is restricted to Korean enrollees, which may limit generalizability to other healthcare systems.
Cited by
- context Pneumonia is the secondary complication that causes death following most hip fractures in elderly patients.