Diabetes was the only comorbid condition associated with mortality of invasive pneumococcal infection in ICU patients: a multicenter observational study from the Outcomerea research group.

PURPOSES: Streptococcus pneumoniae is a leading pathogen of severe community, hospital or nursing facility infections. We sought to describe characteristics of invasive pneumococcal infection (IPI) and pneumonia (due to the high mortality of intensive care-associated pneumonia) and to report outcomes according to various types of comorbidity.

METHODS: Multicenter observational cohort study on the prospective Outcomerea database, including adult patients, with a hospital stay < 48 h before ICU admission and a documented IPI within the first 72 h of ICU admission. Comorbid conditions were defined according to the Knaus and Charlson classification.

RESULTS: Of the 20,235 patients, 5310 (26.4%) had an invasive infection, including 560/5,310 (10.6%) who had an IPI. The ICU 28-day mortality was 109/560 (19.8%). Four factors were independently associated with mortality: SOFA day 1-2: [hazard ratio (HR) 1.21; 95% confidence interval (95% CI) 1.15-1.27, p < 0.001]; maximum lactate level day 1-2: (HR 1.07, 95% CI 1.02-1.12, p = 0.006); diabetes mellitus: (HR 1.91, 95% CI 1.23-3.03, p = 0.006) and appropriate antibiotics (HR 0.28, 95% CI 0.15-0.50, p < 0.001). Comparable results were obtained when other comorbid conditions were forced into the model. Diabetes impact was more pronounced in case of micro- or macro-angiopathy (HR 4.17, 95%CI 1.68-10.54, p = 0.003), in patients ≥ 65 years old (HR 2.59, 95% CI 1.56-4.28, < 0.001) and in those with body mass index (BMI) < 25 kg/m2 (HR 2.11, 95% CI 1.10-4.06, p = 0.025).

CONCLUSIONS: Diabetes mellitus was the only comorbid condition which independently influenced mortality in patients with IPI. Its impact was more pronounced in patients with complications, aged ≥ 65 years and with BMI < 25 kg/m2 .