Diabetes, glycemic control, and risk of hospitalization with pneumonia - A population-based case-control study

OBJECTIVE - To examine whether diabetes is a risk factor for hospitalization with pneumonia and to assess the impact of AlC level on such risk. RESEARCH DESIGN AND METHODS - in this population-based, case-control study We identified patients With a first-time pneumonia-related hospitalization between 1997 and 2005, using health care databases in northern Denmark. For each case, 10 sex- and age-matched population control subjects were selected from Denmark's Civil Registration System. We used conditional logistic regression to compute relative risk (RR) for pneumonia-related hospitalization among subjects with and without diabetes, controlling for potential confounding factors. RESULTS - The study included 34,239 patients with a pneumonia-related hospitalization and 342,390 population Control subjects. The adjusted RR for pneumonia-related hospitalization among subjects with diabetes was 1.26 (95% CI 1,21-1.3.1) compared with nondiabetic individuals. The adjusted RR was 4.43 (3.40-5.77) for subjects with type 1 diabetes and 1.23 (1.19-1.28) for subjects with type 2 diabetes. Diabetes duration >= 10 years increased the risk of,I pneumonia-related hospitalization (1.37 [1.28-1.471). Compared with subjects without diabetes, the adjusted RR was 1.22 (1.14-1.30) for diabetic subjects whose AlC level was <7% and 1.60 (1.44-1.76) for diabetic subjects whose AlC level was >= 9%. CONCLUSIONS - Type 1 and type 2 diabetes are risk factors for a pneumonia-related hospitalization. Poor long-term glycemic control among patients with diabetes clearly increases the risk of hospitalization with pneumonia.