Quality of diabetes care predicts the development of cardiovascular events: Results of the QuED study

Background and aim: In the context of the QuED Study we assessed whether a quality of care summary score was able to predict the development of cardiovascular (CV) events in patients with type 2 diabetes. Methods and results: The score was calculated using process and intermediate outcome indicators (HbA(1c), blood pressure, low-density lipoprotein cholesterol, microalbuminuria) and ranged from 0 to 40. Overall, 3235 patients were enrolled, of whom 492 developed a CV event after a median follow-up of 5 years. The incidence rate (per 1000 person-years) of CV events was 62.4 in patients with a score <= 10, 54.8 in those with a score between 15 and 20, and 39.8 in those with a score > 20. In adjusted multilevel regression models, the risk to develop a CV event was 89% greater in patients with a score of <= 10 (rate ratio [RR] = 1.89; 95% confidence interval [CI] 1.43-2.50) and 43% higher in those with a score between 10 and 20 (RR = 1.43; 95% CI 1.14-1.79), as compared to those with a score > 20. A difference between centers of 5 points in the mean quality score was associated with a difference of 16% in CV event risk (RR = 0.84; 95% CI 0.72-0.98). Conclusion: Our study documented for the first time a close relationship between a score of quality of diabetes care and long-term outcomes. (c) 2006 Elsevier B.V. All rights reserved.