Changes in the glycaemia risk index and its association with other continuous glucose monitoring metrics after initiation of an automated insulin delivery system in adults with type 1 diabetes

Aim: To evaluate the glycaemia risk index (GRI) and its association with other continuous glucose monitoring (CGM) metrics after initiation of an automated insulin delivery (AID) system in patients with type 1 diabetes (T1D). Materials and Methods: Up to 90 days of CGM data before and after initiation of an AID system from 185 CGM users with T1D were collected. GRI and other CGM metrics were calculated using cgmanalysis R software and were analysed for 24 hours, for both night-time and daytime. GRI values were assigned to five GRI zones: zone A (0-20), B (21-40), C (41-60), D (61-80) and E (81-100). Results: Compared with baseline, GRI and its components decreased significantly after AID initiation ( GRI: 48.7 +/- 21.8 vs. 29 +/- 13; hypoglycaemia component: 2.7 +/- 2.8 vs. 1.6 +/- 1.7; hyperglycaemia component: 25.3 +/- 14.5 vs. 15 +/- 8.5; P <.001 for all). The GRI was inversely correlated with time in range before (r = similar to 0.962) and after (r = similar to 0.961) AID initiation (P <.001 for both). GRI was correlated with time above range (before: r = 0.906; after = 0.910; P <.001 for both), but not with time below range (P >.05). All CGM metrics improved after AID initiation during 24 hours, for both daytime and night-time (P <.001 for all). Metrics improved significantly more during night-time than daytime (P <.01). Conclusions: GRI was highly correlated with various CGM metrics above, but not below target range, both before and after AID initiation.

Automated summary

This study aimed to evaluate the glycaemia risk index (GRI) and its association with other continuous glucose monitoring (CGM) metrics after initiation of an automated insulin delivery (AID) system. The study found that GRI was highly correlated with various CGM metrics above target range, but not below.