To evaluate the effects of a collaborative case management intervention for patients with poorly controlled type 2 diabetes on glycemic control, intermediate cardiovascular outcomes, satisfaction with care, and resource utilization.

We conducted a randomized controlled trial at two Department of Veterans Affairs Medical Centers involving 246 veterans with diabetes and baseline hemoglobin A_1C (HbA_1C) levels ≥7.5%. Two nurse practitioner case managers worked with patients and their primary care providers, monitoring and coordinating care for the intervention group for 18 months through the use of telephone contacts, collaborative goal setting, and treatment algorithms. Control patients received educational materials and usual care from their primary care providers.

At the conclusion of the study, both case management and control patients remained under poor glycemic control and there was little difference between groups in mean exit HbA_1C level (9.3% vs. 9.2%; difference = 0.1%; 95% confidence interval: −0.4% to 0.7%; P = 0.65). There was also no evidence that the intervention resulted in improvements in low-density lipoprotein cholesterol level or blood pressure control or greater intensification in medication therapy. However, intervention patients were substantially more satisfied with their diabetes care, with 82% rating their providers as better than average compared with 64% of patients in the control group (P = 0.04).

An intervention of collaborative case management did not improve key physiologic outcomes for high-risk patients with type 2 diabetes. The type of patients targeted for intervention, organizational factors, and program structure are likely critical determinants of the effectiveness of case management. Health systems must understand the potential limitations before expending substantial resources on case management, as the expected improvements in outcomes and downstream cost savings may not always be realized.