Efficacy of switching from insulin glargine to insulin degludec in patients with type 1 diabetes: a 16-week retrospective study.

Abstract

We retrospectively investigated the effect of switching from insulin glargine (IGlar) to insulin degludec (IDeg) on glycemic control in Japanese patients with type 1 diabetes mellitus. We also evaluated the dose of IDeg, and assessed weight gain and the risk of hypoglycemia after switching. Forty-five patients with type 1 diabetes were switched from IGlar (once daily or twice daily) to IDeg (once daily) during routine medical care. Data were collected for 16weeks after switching from IGlar to IDeg. The mean HbA1c (%) in weeks 4, 8, 12, and 16 was lower than it was in week 0 (8.0±1.0, 8.0±1.4, 7.9±1.1, 7.6±1.0 vs. 8.3±1.3%, p<0.01). The total basal insulin dose (TBD) was significantly lower after 16weeks of IDeg as compared to IGlar treatment (0.30±0.12 vs. 0.24±0.11U/kg/day, p=0.001). In the twice-daily IGlar group, TBD showed a significant decrease from 0.33±0.12 to 0.26±0.11U/kg/day (p<0.001) after switching to IDeg. In the once-daily IGlar group, TBD showed a slight but not significant decrease from 0.23±0.08 to 0.20±0.09U/kg/day (p=0.97). Hypoglycemic episodes were transiently increased, but the change was not significant. The blood glucose fluctuation was evaluated from self-monitoring data and the coefficient of variation (CV) was calculated. The CV showed only a minimal change from 48.3±17.1 to 48.6±14.2% at 12weeks after switching to IDeg (p=0.73). In conclusion, once-daily IDeg improved glycemic control in patients with type 1 diabetes compared to the control achieved with IGlar, without increasing the risk of hypoglycemia. When switching from IGlar (especially twice daily), it is recommended that the initial dose of IDeg should be reduced in order to decrease the risk of hypoglycemia.