Delayed initiation of insulin therapy remains a common clinical challenge in type 2 diabetes mellitus (T2DM). A retrospective cohort study published in Diabetes, Metabolic Syndrome and Obesity examined the prevalence, predictors, and clinical consequences of delayed insulin initiation in a tertiary care setting in southern Thailand.

The study included 973 adults with T2DM who initiated insulin therapy between January 1, 2004 and December 31, 2023, at a university hospital. Delayed insulin initiation was defined as starting insulin at least six months after documented treatment failure, defined as glycated hemoglobin (HbA1c) ≥7% while receiving oral agents. Logistic regression identified predictors of delay. Time-to-event analyses and restricted mean survival time were used to compare diabetes-related complications.

Delayed insulin initiation occurred in 35% of patients. Independent predictors included higher body mass index, longer diabetes duration, biguanide use, and diuretic use, whereas dipeptidyl peptidase-4 (DPP-4) inhibitor use was associated with timely initiation. Although no significant differences were observed in overall macrovascular or microvascular complication rates, delayed initiation was associated with increased amputation risk (HR 2.33; 95% CI 1.07-5.07) and earlier onset of microvascular complications within the 10-15-year window (restricted mean survival time difference −0.56 years; P = 0.043).