Effectiveness, Safety, Initial Optimal Dose, and Optimal Maintenance Dose Range of Basal Insulin Regimens for Type 2 Diabetes: A Systematic Review with Meta-analysis

Aims: To investigate the effectiveness, safety, optimal starting dose, optimal maintenance dose range, and target fasting plasma glucose of five basal insulins in insulin-naïve patients with type 2 diabetes mellitus.

Methods: MEDLINE, EMBASE, Web of Science, and the Cochrane Library were searched from January 2000 to February 2022. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed and the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach was adopted. The registration ID is CRD42022319078 in PROSPERO.

Results: Among 11 163 citations retrieved, 35 publications met the planned criteria. From meta-analyses and network meta-analyses, we found that when injecting basal insulin regimens at bedtime, the optimal choice in order of most to least effective might be glargine U-300 or degludec U-100, glargine U-100 or detemir, followed by neutral protamine hagedorn (NPH). Injecting glargine U-100 in the morning may be more effective (ie, more patients archiving glycated hemoglobin < 7.0%) and lead to fewer hypoglycemic events than injecting it at bedtime. The optimal starting dose for the initiation of any basal insulins can be 0.10-0.20 U/kg/day. There is no eligible evidence to investigate the optimal maintenance dose for basal insulins.

Conclusions: The five basal insulins are effective for the target population. Glargine U-300, degludec U-100, glargine U-100, and detemir lead to fewer hypoglycemic events than NPH without compromising glycemic control.