Real-world glycaemic outcomes in patients with type 1 diabetes using glucose sensors—Experience from a single centre in Dublin

Abstract

Aims

To evaluate changes in glycated haemoglobin (HbA₁c) and sensor-based glycaemic metrics after glucose sensor commencement in adults with T1D.

Methods

We performed a retrospective observational single-centre study on HbA₁c, and sensor-based glycaemic data following the initiation of continuous glucose monitoring (CGM) in adults with T1D (n = 209).

Results

We observed an overall improvement in HbA₁c from 66 (59–78) mmol/mol [8.2 (7.5–9.3)%] pre-sensor to 60 (53–71) mmol/mol [7.6 (7.0–8.6)%] on-sensor (p < .001). The pre-sensor HbA₁c improved from 66 (57–74) mmol/mol [8.2 (7.4–8.9)%] to 62 (54–71) mmol/mol [7.8 (7.1–8.7)%] within the first year of usage to 60 (53–69) mmol/mol [7.6 (7.0–8.4)%] in the following year (n = 121, p < .001). RT-CGM-user had a significant improvement in HbA₁c (Dexcom G6; p < .001, r = 0.33 and Guardian 3; p < .001, r = 0.59) while a non-significant reduction was seen in FGM-user (Libre 1; p = .279). Both MDI (p < .001, r = 0.33) and CSII group (p < .001, r = 0.41) also demonstrated significant HbA₁c improvement. Patients with pre-sensor HbA₁c of ≥64 mmol/mol [8.0%] (n = 125), had attenuation of pre-sensor HbA₁c from 75 (68–83) mmol/mol [9.0 (8.4–9.7)%] to 67 (59–75) mmol/mol [8.2 (7.6–9.0)%] (p < .001, r = 0.44). Altogether, 25.8% of patients achieved the recommended HbA₁c goal of ≤53 mmol/mol and 16.7% attained the recommended ≥70% time in range (3.9–10.0 mmol/L).

Conclusions

Our study demonstrated that minimally invasive glucose sensor technology in adults with T1D is associated with improvement in glycaemic outcomes. However, despite significant improvements in HbA₁c, achieving the recommended goals for all glycaemic metrics remained challenging.