A Pilot Study Evaluating Steroid-Induced Diabetes after Antiemetic Dexamethasone Therapy in Chemotherapy-Treated Cancer Patients

Dexamethasone is a mainstay antiemetic regimen for the prevention of chemotherapy-induced nausea and vomiting. The aim of this pilot study was to assess the incidence of and factors associated with steroid-induced diabetes in cancer patients receiving chemotherapy with dexamethasone as an antiemetic. Non-diabetic patients with newly diagnosed gastrointestinal cancer who received at least three cycles of highly or moderately emetogenic chemotherapy with dexamethasone as an antiemetic were enrolled. Fasting plasma glucose levels, 2-hour postprandial glucose levels, and hemoglobin A tests for the diagnosis of diabetes were performed before chemotherapy and at 3 and 6 months after the start of chemotherapy. The homeostasis model assessment of insulin resistance (HOMA-IR) was used as an index for measurement of insulin resistance, defined as a HOMA-IR ≥ 2.5. Between January 2012 and November 2013, 101 patients with no history of diabetes underwent laboratory tests for assessment of eligibility; 77 of these patients were included in the analysis. Forty-five patients (58.4%) were insulin resistant and 17 (22.1%) developed steroid-induced diabetes at 3 or 6 months after the first chemotherapy, which included dexamethasone as an antiemetic. Multivariate analysis showed significant association of the incidence of steroid-induced diabetes with the cumulative dose of dexamethasone (p=0.049). We suggest that development of steroid-induced diabetes after antiemetic dexamethasone therapy occurs in approximately 20% of non-diabetic cancer patients; this is particularly significant for patients receiving high doses of dexamethasone.