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 1.21–1.31) 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 duration10 years increased the risk of
a pneumonia-related hospitalization (1.37 [1.28 –1.47]). Compared with subjects without diabetes,
the adjusted RR was 1.22 (1.14 –1.30) for diabetic subjects whose A1C level was7% and
1.60 (1.44 –1.76) for diabetic subjects whose A1C level was 9%.