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

• Published in: Diabetes, obesity & metabolism obesity & metabolism, 2015-10, Vol.17 (10), p.956-964
• Main Authors: Inzucchi, S. E., Tunceli, K., Qiu, Y., Rajpathak, S., Brodovicz, K. G., Engel, S. S., Mavros, P., Radican, L., Brudi, P., Li, Z., Fan, C. P. S., Hanna, B., Tang, J., Blonde, L.
• Format: Article
• Language: English
• Subjects: Aged; Antidiabetics; Cohort analysis; Confidence intervals; database research; Diabetes; Diabetes mellitus (non-insulin dependent); Diabetes Mellitus, Type 2 - drug therapy; DPP-IV inhibitor; Drug Administration Schedule; Drug Prescriptions - statistics & numerical data; Drug Therapy, Combination; Electronic medical records; Female; Health risk assessment; Humans; Hypoglycemic Agents - administration & dosage; Insulin; Insulin - administration & dosage; insulin therapy; Kaplan-Meier Estimate; Male; Medical records; Metformin; Metformin - administration & dosage; Middle Aged; Original; Propensity Score; Regression analysis; Retrospective Studies; Sitagliptin Phosphate - administration & dosage; Sulfonylurea Compounds - administration & dosage; sulphonylureas; Time Factors; type 2 diabetes
• ISSN: 1462-8902; 1463-1326
• DOI: 10.1111/dom.12489

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