GLYCAEMIC OUTCOMES FOLLOWING INSULIN DE-INTENSIFICATION IN PATIENTS WITH TYPE 2 DIABETES MELLITUS

A RETROSPECTIVE OBSERVATIONAL STUDY IN A MALAYSIAN TERTIARY CENTRE

Abstract

INTRODUCTION
Insulin deintensification is the reduction, simplification, or cessation of insulin therapy. Despite its potential benefits, there is limited local data on real-world insulin deintensification practices. We investigated the impact of insulin deintensification on glycemic control among patients with type 2 diabetes mellitus (T2DM) attending outpatient follow-up at a Malaysian tertiary hospital.

METHODOLOGY
We conducted a retrospective observational study at the outpatient clinic of Hospital Sungai Buloh from January to December 2024. Adults with T2DM who underwent insulin deintensification were included. Patients with type 1 diabetes, gestational diabetes, or incomplete follow-up data were excluded. Primary outcomes were changes in HbA1c and pre-breakfast blood glucose (BG) levels. Secondary outcomes examined associations between diabetes duration and baseline HbA1c with glycemic outcomes. Paired t-tests and correlation coefficient tests were used for statistical analyses.

RESULT
A total of 33 patients were included. Most (n = 22) were initially on a basal-bolus regimen and subsequently de-intensified to premixed human insulin (n = 12), premixed analogue insulin (n = 7), oral agents (n = 2), or basal-only insulin (n = 1). Among nine patients initially on human premixed insulin, five were switched to a premixed analogue regimen, two to oral agents, one to basal-only insulin, and one to basal analogue. Of the two patients on basal insulin, one transitioned to oral agents and the other to a premixed analogue regimen. Nineteen patients had complete paired HbA1c data, with mean HbA1c improving from 10.36% (SD 2.70) to 8.93% (SD 2.49) (mean change −1.43%, p = 0.003). Fifteen patients had complete pre-breakfast BG data, showing a mean reduction from 12.07 mmol/L (SD 3.86) to 9.90 mmol/L (SD 3.22) (p = 0.037). Baseline HbA1c strongly correlated with follow-up HbA1c (r = 0.76, p <0.001). Meanwhile, diabetes duration showed no significant association (r = −0.24, p = 0.365).

CONCLUSION
Insulin deintensification was associated with significant improvements in HbA1c and pre-breakfast BG levels, supporting its safe implementation in selected patients with T2DM. Baseline HbA1c was a strong predictor of post-intervention control. These findings highlight the potential for regimen simplification with structured follow-up and monitoring.