The impact of serum glucose on clinical outcomes in patients hospitalized with community-acquired pneumonia.

Purpose: Community-acquired pneumonia (CAP) is a common medical condition resulting in excess morbidity, mortality, and high rates of hospitalization. Despite high hospitalization rates for CAP, the relationship between abnormal glucose levels (hyperglycemia and hypoglycemia) and the seriousness of the illness as measured by length of stay (LOS) is not well established. We examined relationships of CAP to multiple factors that impact predictability and severity of the disease process. They include glycemic control; hospital utilization, including LOS; 30-day hospital readmission; intensive care unit (ICU) admissions, adjusting for comorbidities; illness severity; and timing of antibiotic treatment.

Methods: We conducted a retrospective observational cohort study of adult patients hospitalized for CAP between January 1, 1992 and June 23, 2007. Case screening was conducted electronically using International Classification of Diseases, 9th Revision (ICD-9) codes 480.0-487.9. Subsequent medical record abstraction yielded 969 qualifying cases with comprehensive data on past and current medical problems.

Results: Serum glucose levels at admission were independently associated with LOS for CAP patients. Patients with levels between 90 mg/dL and 140 mg/dL on admission had shorter LOS compared to those with levels of < 90 mg/dL and > 140 mg/dL (median 3.9 vs 4.2 days, P = .04). Multivariate analyses confirmed the univariate results. Serum glucose levels at initial hospitalization were not associated with 30-day hospital readmission (P =.34) or ICU admission (P = .48).

Conclusions: Abnormal glucose levels are an independent predictor of increased LOS for CAP. Control of blood glucose may lead to improved outcomes, including shortened LOS, and should be a priority in CAP management.