Abstract
BACKGROUND: Numerous patients develop diabetes in response to glucocorticoid therapy. This study explored the efficacy, safety, and preventive potential of the dipeptidyl peptidase-4 inhibitor, linagliptin (TRADJENTA®), in the development of glucocorticoid-induced diabetes mellitus. METHODS: From December 2014 to November 2015, we recruited non-diabetic Japanese patients scheduled for treatment with daily prednisolone ≥20 mg. Enrolled patients had at least one of following risk factors for glucocorticoid-induced diabetes mellitus: estimated glomerular filtration rate ≤ 60 mL/minute/1.73 m(2); age ≥ 65 years; hemoglobin A1c > 6.0%. A daily dose of 5 mg of linagliptin was administered simultaneously with glucocorticoid therapy. The primary outcome was the development of glucocorticoid-induced diabetes mellitus. Additional orally administered hypoglycemic medications and/or insulin injection therapy was initiated according to the blood glucose level. RESULTS: Four of five patients developed glucocorticoid-induced diabetes mellitus within 1 week of glucocorticoid treatment. For 12 weeks, two of the four patients with glucocorticoid-induced diabetes mellitus required orally administered medications, but no patients required insulin. Blood glucose levels before breakfast and lunch tended to decrease with time; the median glucose levels before breakfast were 93 and 79.5 mg/dL at 1 and 3 weeks, respectively. Two patients experienced mild hypoglycemia around 2 weeks. Glucose levels after lunch remained high throughout all 4 weeks despite decreasing the glucocorticoid dosage. CONCLUSIONS: Linagliptin may be insufficient to prevent the development of glucocorticoid-induced diabetes mellitus but has the potential to reduce the requirement for insulin injection therapy. Treatment of glucocorticoid-induced diabetes mellitus was continued for at least 1 month and fasting hypoglycemia in early morning should be monitored after 2 weeks. TRIAL REGISTRATION: This trial was registered 02 November 2014 with UMIN Clinical Trials Registry (no. 000015588 ).