Time in uncontrolled hyperglycemia before insulin initiation in people living with type 2 diabetes: A systematic literature review

This systematic literature review (PROSPERO registration: CRD42022327974) examined the duration of uncontrolled hyperglycemia (glycated hemoglobin [HbA_1c] ≥ 7.0%; ≥ 53 mmol/mol) before basal insulin initiation in insulin-naive people with type 2 diabetes who were receiving concomitant oral glucose-lowering agents or injectable glucagon-like peptide-1 receptor agonist therapy.

Databases (Embase and MEDLINE) were searched to identify relevant articles published between January 1, 2001, and April 19, 2023. Supplementary searches were completed for relevant congresses between 2018 and 2023.

Of the 4260 de-duplicated publications identified, 18 eligible publications (conducted in: Europe, n = 5; USA, n = 8; Asia/Middle East, n = 4; and Africa, n = 1) reported time spent with HbA_1c 7.0% or higher (≥ 53 mmol/mol). Overall, time in uncontrolled hyperglycemia ranged from 1.9 months to 86.4 months (Europe, 9.0-86.4 months; USA, 1.9-58.3 months; Asia/Middle East, 3.3-40.1 months; Africa, 36 months).

There is a widespread delay in insulin treatment initiation in clinical practice. This delay exists despite availability of novel insulin types and the development of evidence-based treatment guidelines, suggesting that further efforts are needed to improve implementation of these guidelines in clinical practice.