Epidemiology, clinical features and outcomes of pneumonia in patients with chronic kidney disease

Background. Although infection remains among the most common causes of morbidity and mortality in patients with chronic kidney disease (CKD), data on epidemiology, clinical features and outcomes of pneumonia in this population are scarce. Methods. Observational analysis of a prospective cohort of hospitalized adults with pneumonia, between 13 February 1995 and 30 April 2010, in a tertiary teaching hospital. CKD patients, defined as patients with a baseline glomerular filtration rate < 60 mL/min/1.73m(2), were compared with non-CKD patients. Results. During the study period, 3800 patients with pneumonia required hospitalization. Two-hundred and three (5.3%) patients had CKD, of whom 46 were on dialysis therapy. Patients with CKD were older (77 versus 70 years; P < 0.001), were more likely to have comorbidities (82.3 versus 63.3%; P < 0.001) and more commonly classified into high-risk pneumonia severity index classes (89.6 versus 57%; P < 0.001) than were the remaining patients. Streptococcus pneumoniae was the most frequent pathogen (28.1 versus 34.7%; P = 0.05). Mortality was higher in patients with CKD (15.8 versus 8.3%; P < 0.001). Among CKD patients, age [+1 year increase; adjusted odds ratio, 1.25; 95% confidence interval (CI) 1.07-1.46] and cardiac complications during hospitalization (adjusted odds ratio, 9.23; 95% CI 1.39-61.1) were found to be independent risk factors for mortality, whereas prior pneumococcal vaccination (adjusted odds ratio, 0.05; 95% CI 0.005-0.69) and leukocytosis at hospital admission (adjusted odds ratio, 0.10; 95% CI 0.01-0.64) were protective factors. Conclusions. Pneumonia is a serious complication in CKD patients. Independent factors for mortality are older age and cardiac complications, whereas prior pneumococcal vaccination and leucokytosis at hospital admission are protective factors. These findings should encourage physicians to increase pneumococcal vaccine coverage among CKD patients.