Quality of care for patients with Type 2 diabetes mellitus - A long-term comparison of two quality improvement programmes in the Netherlands

Aim: To compare two intervention programmes, aimed at improving the quality of care provided for patients with Type 2 diabetes in the longer term. Methods: A retrospective comparison of data derived from two non-randomized trials with 3.5 years of follow-up. In the first intervention group 401 patients were included, 413 in the second intervention group and 105 in the reference group. The first programme focused on improving the skills and knowledge of general practitioners (GPs) with regard to Type 2 diabetes, and supported them in making organizational changes in their practice (GP care only). Centralized shared diabetes care was implemented in the second programme in which the GPs received therapy advice according to a protocol for each individual patient. The patients were also encouraged in self-management, and received structured diabetes education (Diabetes Service). The main patient outcomes were HbA_1c, blood pressure and serum lipid levels. Multilevel analysis was applied to adjust for dependency between repeated observations within one patient and for clustering of patients within general practices. Results: The HbA_1c levels of patients of GPs who were supported by the Diabetes Service improved significantly more than the HbA_1c levels of patients receiving GP care only {-0.28% [95% confidence interval (CI) -0.45; -0.11]}. In contrast, the systolic blood pressure of patients receiving GP care only decreased more than that of patients of GPs supported by the Diabetes Service [4.14 mmHg (95% CI 1.77, 6.51)]. Conclusion: A Diabetes Service, providing GPs with individual therapy advice and patient education, resulted in better glycaemic control over 3.5 years than an intervention aimed at improving the skills of GPs in combination with organizational changes in the general practice.