The impact of closed-loop automated insulin delivery systems on hypoglycaemia awareness in people living with type 1 diabetes: a systematic review and meta-analysis

Abstract

Objectives: Impaired awareness of hyperglycaemia (IAH) affects approximately 20-40% of people living with type 1 diabetes (T1D), predisposing them to severe hypoglycaemia. This systematic review evaluated the efficacy of closed-loop automated insulin delivery systems (CL-AID) in restoring IAH compared with standard diabetes care, including other diabetes technologies.

Methods: Six electronic databases were searched for published and unpublished observational and randomised-control studies (RCTs) from inception to 29th of May 2024. The results of observational studies and RCTs were meta-analysed separately to calculate the effect of CL-AID on IAH in people living with T1D. Quality assessment of studies was performed using the Joanna-Briggs appraisal tool for cohort studies and the Risk of Bias (Rob-2) tool for RCTs.

Results: Meta-analysis of four prospective observations studies (n = 583) demonstrated a statistically significant improvement in hypoglycaemia awareness upon transition to a hybrid closed-loop (HCL) system compared with standard diabetes care in people with T1D, Clarke score mean difference (MD) of -0.45 (-0.69 to -0.22, p = 0.0001). However, this was less than 1 point, which is the minimum clinically important difference (MCID) of Clarke score. Meta-analysis of three RCTs (n = 55) comparing standard diabetes care did not demonstrate any statistically significant effect on hypoglycaemia awareness, Clarke score MD of -0.69 (-1.89 to 0.50, p = 0.26).

Conclusions: This systematic review demonstrated that transition from standard diabetes care to HCL has the potential to improve hypoglycaemia awareness in people with T1D and IAH, but this might not be of major clinical significance. Hence, psychoeducational interventions continue to be the cornerstone of IAH management. Novel therapeutic modalities, such as bi-hormonal automated delivery systems, need to be further explored to help restore hypoglycaemia awareness.