Hospital-based analysis of risk factors for severe pneumonia patients before and during the COVID-19 pandemic in Wuhan, China

This retrospective cohort study examined 693 elderly patients (≥65 years) with severe pneumonia admitted to Renmin Hospital of Wuhan University, assessing risk factors across two periods: pre-pandemic, during China's zero-Covid policy. Using logistic regression and Cox models, we found notable shifts in risk factor associations. Before the pandemic, chronic kidney disease significantly increased the odds of severe pneumonia (OR: 1.69, 95% CI: 1.45-1.81). During the pandemic, hazard ratios rose for endotracheal intubation (72%), ischemic heart disease (80%), and hospital stays (30%), while hypertension showed a decreased association with severe pneumonia from HR: 0.8 (95% CI: 0.49, 1.32) to HR: 0.61(95% CI: 0.45, 0.85). These findings suggest that pneumonia severity intensified during the pandemic, possibly reflecting healthcare disruptions or delayed care. Elderly patients, especially those with chronic conditions, would benefit from strengthened community-based health interventions to improve outcomes and resilience against future respiratory infections.