Cost-effectiveness of a quality improvement collaborative focusing on patients with diabetes

Objective: To investigate the lifelong health effects, costs, and cost-effectiveness of a quality improvement collaborative focusing on improving diabetes management in an integrated care setting. Study design and methods: Economic evaluation from a healthcare perspective with lifetime horizon alongside a nonrandomized, controlled, before-after study in the Netherlands. Analyses were based on 1861 diabetes patients in 6 intervention and 9 control regions, representing 37 general practices and 13 out-patient clinics. Change in the United Kingdom Prospective Diabetes Study score, remaining lifetime, and costs per quality-adjusted life year gained were calculated. Probabilistic life tables were constructed using the United Kingdom Prospective Diabetes Study risk engine, a validated diabetes model, and nonparametric bootstrapping of individual patient data. Results: Annual United Kingdom Prospective Diabetes Study risk scores reduced for cardiovascular events (hazard ratio: 0.83 and 0.98) and cardiovascular mortality (hazard ratio: 0.78 and 0.88) for men and women, respectively. Life expectancy improved by 0.97 and 0.76 years for men and women, and quality-adjusted life years by 0.44 and 0.37, respectively. Higher life expectancy in the intervention group increased lifelong costs by €860 for men and €645 for women. Initial program costs were about €22 per patient. The incremental costs per quality-adjusted life year were €1937 for men and €1751 for women compared with usual care costs. There is a probability >95% that the collaborative is cost-effective, using a threshold of €20,000 per quality-adjusted life year. Conclusion: Optimizing integrated and patient-centered diabetes care through a quality-improvement collaborative is cost-effective compared with usual care.