OBJECTIVES: To evaluate the effectiveness of insulin plus sodium-glucose cotransporter-2 (SGLT2) inhibitors versus insulin alone among those with type 1 diabetes.

METHODS: This retrospective review involved observational analysis of the T1D exchange clinical registry. Two data sets (2015-2016 and 2016-2017) were assessed comparing insulin and SGLT2 inhibitors (SGLT2 cohort) versus insulin only users (insulin cohort) to manage their type 1 diabetes. Exclusion criteria were: patients lacking a medication record, with reported use of prescription medications other than SGLT2 inhibitors or insulin, or reported pregnancy during or previous year of their clinical visit. Propensity score was used to match insulin only users with those using SGLT2 inhibitors plus insulin. Unpaired t and Mann Whitney tests were used to compare age, body mass index (BMI) total daily insulin units, and the glycated hemoglobin (A1C), between the comparative groups. Two-way mixed analysis of variance (ANOVA) assessed change in total daily insulin units and A1C between the two groups. Stepwise linear regression assessed characteristics associated with A1C.

RESULTS: The SGLT2 cohort (n=70, A1C=7.86±1.05) reported significantly higher A1C (p=0.01) in the clinic visit recorded for 2015-2016 in comparison to the insulin only cohort (n=83, A1C=7.44±1.00). Mixed ANOVA found A1C (p=0.003) and total daily insulin units (p<0.001) in the SGLT2 cohort were significantly higher between 2015 and 2017 in comparison to the insulin only cohort. Stepwise linear regression found A1C level was significantly and positively associated with use of SGLT2 inhibitors and negatively associated with age and annual income.

CONCLUSIONS: This analysis found in a real-world cohort off-label use of SGLT2 inhibitors to be associated with higher total daily insulin units and A1C in comparison to a propensity matched cohort that only used insulin.