Concomitant oral antihyperglycemic agent use and associated treatment outcomes after initiation of insulin therapy.

Objective: To compare outcomes in patients with type 2 diabetes initiating insulin lispro mix 75/25 (75% insulin lispro protamine suspension and 25% lispro) or insulin glargine therapy, stratified by baseline oral antihyperglycemic agent (OHA) use.

Methods: We performed a post hoc analysis of 6-month data from the DURABLE clinical trial, which enrolled patients with hemoglobin A1c (A1C) levels >7.0% treated with 2 or more OHAs (metformin, sulfonylurea, and thiazolidinedione), and randomly assigned them to treatment with twice-daily insulin lispro 75/25 or once-daily glargine.

Results: In both insulin treatment groups, metformin/thiazolidinedione-treated patients had significantly greater improvement in A1C levels (-2.19% to -2.36%), lower end point A1C values, and lower rates of occurrence of hypoglycemia in comparison with metformin/sulfonylurea-treated patients (all P<.05). Patients treated with sulfonylurea/thiazolidinedione or metformin/sulfonylurea/thiazolidinedione did not differ significantly from metformin/sulfonylurea-treated patients in A1C change (-1.56% to -1.84%) or rates of occurrence of hypoglycemia.

Conclusion: In these post hoc analyses, patients with type 2 diabetes initiating premixed or basal insulin therapy and treated concomitantly with the OHA combination of metformin/thiazolidinedione at baseline demonstrated significantly greater A1C improvement with less hypoglycemia in comparison with patients treated with metformin/sulfonylurea.