Disease management for diabetes mellitus: impact on hemoglobin A1c

To describe outcomes associated with a health maintenance organization (HMO)-sponsored disease management program for diabetes. Descriptive study that compared outcomes of patients with diabetes before and after entry into a disease management program. The study was conducted in a mixed-model HMO with 275,000 members. The disease management program included a Steering Committee, clinical guidelines, primary care site-based diabetes education, coverage of glucose meters and strips, simplified outcomes reporting, and support of clinical leadership. Data were obtained for 5332 continuously enrolled patients who voluntarily entered the disease management program; 3291 patients (61.7%) received 3 months or more of follow-up, and 663 (12.4%) received 1 year or more of follow-up. The primary outcomes were change from baseline of mean hemoglobin A1c (HbA1c) and medication use after 3 months and 1 year of follow-up. The mean baseline HbA1c for all program participants was 8.51% (standard deviation [SD] = 1.86%). At 3 months of follow-up, the mean HbA1c value for 2794 of 3291 participants (84.0%) had decreased to 7.41% (SD = 1.33%; P = .0001). At 1 year of follow-up, the HbA1c value, available for 605 of 663 patients (91.3%), had decreased from a mean baseline value of 8.76% (SD = 1.87%) to 7.41% (SD = 1.24%; P = .0001). Among 663 patients with 1 year of follow-up, insulin use increased from 30.0% to 31.6%, and sulfonylurea use decreased from 40.7% to 33.8%. Troglitazone and metformin use increased from 7.7% and 23.8%, respectively, to 16.4% and 28.8%, respectively. Our data suggest that a multifaceted disease management program for diabetes can result in significant short-term improvements in glycemic control in the managed care setting. While the improvement in the HbA1c was accompanied by an increase in the use of insulin, troglitazone, and metformin, we suggest the influence of disease management on glycemic control among our participants was significant and should be considered in future studies in this area.