ABSTRACT: OBJECTIVE:Early use of insulin after diagnosis of type 2 diabetes is met with resistance because of associated weight gain, hypoglycemia, and fear of decreased compliance and quality of life (QoL). RESEARCH DESIGN AND METHODS:In treatment-naive patients with newly diagnosed type 2 diabetes, insulin and metformin were initiated for a 3-month lead-in period, then patients were randomly assigned to insulin and metformin (insulin group) or metformin, pioglitazone, and glyburide (oral group) for 36 months. Hypoglycemic events, compliance, A1C, weight, QoL, and treatment satisfaction were assessed. RESULTS:Of 29 patients randomly assigned into each group, 83% (insulin group) and 72% (oral group) completed this 3-year study. At study completion, A1C was 6.1 +/- 0.6% (insulin group) versus 6.0 +/- 0.8% (oral group). Weight increased similarly in both groups (P = 0.09) by 4.47 kg (95% CI 0.89-8.04 kg) (insulin group) and 7.15 kg (95% CI 4.18-10.13 kg) (orals group). Hypoglycemic events did not differ between groups (mild 0.51 event/person-month in the insulin group vs. 0.68 event/person-month in the orals group, P = 0.18 and severe 0.04 event/person-year in the insulin group vs. 0.09 event/person-year in the orals group, P = 0.53). Compliance, QoL, and treatment satisfaction were similar between groups, with 100% of patients randomly assigned to insulin willing to continue such treatment. CONCLUSIONS:When compared with a clinically equivalent treatment regimen, insulin-based therapy is effective and did not cause greater weight gain or hypoglycemia nor decrease compliance, treatment satisfaction, or QoL. Insulin is safe, well-accepted, and effective for ongoing treatment of patients with newly diagnosed type 2 diabetes.