Predictors of in-hospital mortality of older patients admitted for community-acquired pneumonia.

Background: there were a few studies on the case mortality of pneumonia in older people, of which results were conflicting.

Objectives: this study aimed to identify risk factors associated with in-hospital mortality in older patients admitted for community-acquired pneumonia (CAP).

Design: a prospective cohort study.

Setting: hospital sample.

Subjects: during the 1-year study period (from October 2009 to September 2010), 488 older patients aged 65 or above were recruited.

Methods: demographic characteristics, medical illnesses (Charlson's comorbidity index (CCI)), premorbid functional status (Katz's index) and baseline blood tests were recorded. The outcome was in-hospital mortality.

Results: in this cohort of patients, the mean age was 81.0 years (±7.9) and 282 (57.8%) were male. Nursing home residents accounted for 23.8% (116/488) of study subjects. The median CCI was 2 (inter-quartile range (IQR): 1-3); 60 (12.3%) patients succumbed during hospital stay. Logistic regression showed that comorbidities, mid-arm circumference, serum albumin level and severity of pneumonia (Confusion, blood Urea nitrogen, Respiratory rate and low Blood pressure (CURB) score) were independent predictors of in-hospital mortality of pneumonia.

Conclusion: in keeping with previous studies, CURB score and comorbidities were the most significant independent predictors of mortality of CAP in older patients. Our study concluded that nutritional status was also an important factor affecting their survival. This study failed to demonstrate functional status as a predictor of mortality due to limitation of Katz's index.