Progression to insulin therapy among patients with type 2 diabetes treated with sitagliptin or sulphonylurea plus metformin dual therapy

Diabetes Obes Metab. 2015 Oct;17(10):956-64. doi: 10.1111/dom.12489. Epub 2015 Jun 22.


Aim: To assess time to insulin initiation among patients with type 2 diabetes mellitus (T2DM) treated with sitagliptin versus sulphonylurea as add-on to metformin.

Methods: This retrospective cohort study used GE Centricity electronic medical records and included patients aged ≥18 years with continuous medical records and an initial prescription of sitagliptin or sulphonylurea (index date) with metformin for ≥90 days during 2006-2013. Sitagliptin and sulphonylurea users were matched 1 : 1 using propensity score matching, and differences in insulin initiation were assessed using Kaplan-Meier curves and Cox regression. We used conditional logistic regression to examine the likelihood of insulin use 1-6 years after the index date for each year.

Results: Propensity score matching produced 3864 matched pairs. Kaplan-Meier analysis showed that sitagliptin users had a lower risk of insulin initiation compared with sulphonylurea users (p = 0.003), with 26.6% of sitagliptin users initiating insulin versus 34.1% of sulphonylurea users over 6 years. This finding remained significant after adjusting for baseline characteristics (hazard ratio 0.76, 95% confidence interval 0.65-0.90). Conditional logistic regression analyses confirmed that sitagliptin users were less likely to initiate insulin compared with sulphonylurea users [odds ratios for years 1-6: 0.77, 0.79, 0.81, 0.57, 0.29 and 0.75, respectively (p < 0.05 for years 4 and 5)].

Conclusions: In this real-world matched cohort study, patients with T2DM treated with sitagliptin had a significantly lower risk of insulin initiation compared with patients treated with sulphonylurea, both as add-on to metformin.

Keywords: DPP-IV inhibitor; database research; insulin therapy; sulphonylureas; type 2 diabetes.

MeSH terms

  • Aged
  • Diabetes Mellitus, Type 2 / drug therapy*
  • Drug Administration Schedule
  • Drug Prescriptions / statistics & numerical data*
  • Drug Therapy, Combination
  • Female
  • Humans
  • Hypoglycemic Agents / administration & dosage*
  • Insulin / administration & dosage*
  • Kaplan-Meier Estimate
  • Male
  • Metformin / administration & dosage*
  • Middle Aged
  • Propensity Score
  • Retrospective Studies
  • Sitagliptin Phosphate / administration & dosage*
  • Sulfonylurea Compounds / administration & dosage*
  • Time Factors


  • Hypoglycemic Agents
  • Insulin
  • Sulfonylurea Compounds
  • Metformin
  • Sitagliptin Phosphate