Efficacy of Low-dose Dapagliflozin in Young People with Type 1 Diabetes

OBJECTIVE: Young people with type 1 diabetes are likely to gain body weight and not achieve optimal glycemic control with only high doses of insulin. This study examined the efficacy of the sodium-glucose cotransporter 2 (SGLT2) inhibitor dapagliflozin as an adjunct-to-insulin therapy in young Japanese subjects with type 1 diabetes who had been diagnosed before 15 years old, were overweight, and had inadequate control despite receiving intensive insulin therapy. METHODS: Twenty-two patients with type 1 diabetes (12 boys and 10 girls 16.0-33.9 years old) were involved in the study. All patients had a body mass index (BMI) ＞25 kg/m(2), glycated hemoglobin (HbA1c) level ＞7.0%, and daily insulin dose ＞0.5 units/kg. They were treated with a low dose of dapagliflozin (5.0 mg/day) as an adjunctive therapy to insulin. Fourteen patients were treated with multiple daily injections of insulin, while eight used an insulin pump. RESULTS: The body weights and BMIs were significantly reduced during the 12-month study period (change of -4.4 kg and -1.7 kg/m(2), p＜0.001, respectively). Their insulin dose was significantly decreased (-0.17 units/kg, P ＜0.001), and glycemic control was significantly improved (fasting plasma glucose: -18.7 mg/dL, HbA1c: -0.62%, p＜0.001) during the study period. There was one episode of diabetic ketoacidosis, with no other problematic adverse events, including severe hypoglycemia, observed. CONCLUSION: The use of low-dose dapagliflozin as an adjunct therapy may be beneficial in overweight young people with poorly controlled type 1 diabetes.