Predictors of mortality in nursing-home residents with pneumonia: a multicentre study

Abstract

Objectives: To evaluate predictors of mortality in patients residing in nursing-homes (NHs) or long-term care facilities (LTCFs) with diagnosis of NH-acquired pneumonia (NHAP).

Methods: We conducted an observational, prospective study (December 2013-December 2015) of patients residing in nine NHs/LTCFs of Central and Northern Italy with diagnosis of NHAP. Data on demographics, comorbidities, microbiology, and therapies were entered into an electronic database. To identify risk factors associated with 30-day mortality, we performed univariable and multivariable analyses, and predictors were internally validated using a bootstrap resampling procedure. We derived a prediction rule using the coefficients obtained from the multivariable logistic regression. The model obtained was assessed using the area under the receiver operating characteristic curve (AUROC).

Results: Overall, 446 patients with NHAP were included in the final cohort. The median age was 80 (IQR 75-87) years. A definite aetiology was obtained in 120 (26.9%) patients; of these, 66 (55%) had a culture positive for a multidrug-resistant pathogen. The 30-day mortality was 28.7%. On multivariate analysis, malnutrition (OR 7.8; 95% CI 3-20.2, 2 points), bilateral pneumonia (OR 3.7; 95% CI 1.4-9.8, 1 point), acute mental status deterioration (OR 6.2; 95% CI 2.2-17.6, 2 points), hypotension (OR 7.7; 95% CI 2.3-24.9, 2 points), and PaO₂/FiO₂ ratio ≤250 (OR 7.4; 95% CI 2.2-24.2, 2 points) were independently associated with 30-day mortality. The derived prediction rule showed an AUROC of 0.83 (95% CI 0.78-0.87, p <0.001).

Conclusions: NH residents with pneumonia have specific risk factors associated with 30-day mortality. Malnutrition and acute mental change appear as major determinants of death in this population.

Keywords: Delirium; Elderly patient; Long-term care facility; Malnutrition; Nursing-home; Pneumonia.