Nosocomial febrile illness in the elderly: frequency, causes, and risk factors

Although nosocomial febrile illness (NFI) is common in hospitalized patients, it has been less extensively studied in the elderly.

To determine the frequency, causes, and risk factors of NFI in elderly inpatients.

This prospective study involved 608 patients (> or = 65 years of age) admitted in an acute geriatric unit. Investigators followed this cohort until 1 of the following events occurred: development of NFI, discharge from the geriatric unit, or death. The cause of NFI was classified into 3 groups: infectious, noninfectious, and no apparent diagnosis. We systematically studied 17 comorbid conditions, 6 drugs, and 7 invasive procedures. For comparison, the patients were stratified into 2 groups: patients with NFI and patients without NFI.

Sixty-six patients (10.9%) with NFI were identified. They were compared with the remaining 542 patients without NFI. In 49 patients (74%) with NFI, the cause was infectious; in 9 (13.5%), it was noninfectious; and in 8 (12.5%), there was no apparent cause. After multivariate analysis, only fecal incontinence (odds ratio [OR], 5.54; 95% confidence interval [CI], 2.13-14.5), congestive heart failure (OR, 2.97; 95% CI, 1.53-5.76), and pressure ulcers (OR, 2.93; 95% CI, 1.19-7.17) were independent risk factors for NFI. The number of invasive procedures preceding the febrile episode was a significant predictor of infection (OR, 3.68; 95% CI, 1.14-9.21).

Nosocomial febrile illness is a common event in elderly hospitalized patients. In 74% of the patients with NFI, an infection is found. Measures to decrease infectious NFI in the elderly require a reduction in the number of invasive procedures.