Clinical study on common infections and mortality among 40 000 geriatric patients hospitalized in Stockholm, Sweden

Purpose While pneumonia, bacteremia and urinary tract infection (UTI) are frequently seen in geriatric care, large-scale comparative analyses on their fatality are lacking. The aim was to evaluate the fatality of these infections in hospitalized older adults. Methods Data comprised 46,068 patients aged ≥60 years admitted to geriatric clinics in Stockholm between March 2020 and December 2022. Patients were classified by ICD-10 diagnoses into infection groups: bacteremia, pneumonia, UTI, Covid-19 with or without pneumonia, and the patients without these infections(reference). Thirty-day mortality risk was assessed using multivariable logistic regression adjusted for age, sex, comorbidity (Charlson Comorbidity Index[CCI], and frailty (Hospital Frailty Risk Score[HFRS]). Results In the reference group, mortality rate was 4.6%. Covid-19–pneumonia had the highest fatality rate (17%) and adjusted odds of death (OR:4.9), followed by bacteremia (12%; OR:2.5), pneumonia (9.3%; OR:1.9), and Covid-19 (11.0%; OR:2.7). UTI showed the lowest fatality and opposite direction of association (3.7%; OR:0.68). The analyses were additionally repeated stratified by six periods corresponding to the Covid-19 waves in society. Across the study periods, fatality of bacteremia (rates 8–15%; adjusted ORs:2.4–2.9, p<0.05) and pneumonia (6–13%; ORs:1.9–2.2, p<0.05) remained consistently high. In contrast, Covid-19–pneumonia and Covid-19 showed declining fatality rates from 29% to 7% and 17% to 4%, respectively, with corresponding ORs decreasing from 7.1 to 1.7 and from 4.5 to 0.98. Conclusion The findings reinforce the significant clinical burden of bacteremia and pneumonia in older adults and underscore the need for early recognition, targeted preventive and management strategies within geriatric care settings.