Incidence and Risk Factors of Steroid-induced Diabetes in Patients with Respiratory Disease

Glucocorticoids are effective for treating several respiratory diseases. However, they can cause hyperglycemia. This study determined the incidence and risk factors of steroidinduced diabetes mellitus (S-DM) in patients treated with glucocorticoid for respiratory diseases. A retrospective study examined patients with respiratory diseases treated with a prednisolone-equivalent glucocorticoid dose exceeding 20 mg/day for at least 4 weeks between January 2003 and December 2008. Patients whose initial random glucose level exceeded 200 mg/dL or who had pre-existing diabetes were excluded. S-DM was defined as a fasting glucose concentration exceeding 126 mg/dL or a random glucose concentration exceeding 200 mg/dL at least twice after beginning steroid treatment. A total of 231 patients with respiratory diseases met the inclusion criteria. Their median age was 55 yr, and 139 were female. The median cumulative prednisolone-equivalent glucocorticoid dose was 4,965 mg, and the median duration of steroid treatment was 193 days. S-DM was diagnosed in 34 (14.7%) of 231 patients. Multivariate logistic regression identified older age (odds ratio 1.05, 95% confidence interval 1.02-1.09) as a risk factor for S-DM. S-DM is frequent among patients with respiratory diseases treated with glucocorticoid. Clinicians should be aware of the possibility of S-DM, especially among elderly patients.