Regional differences of glycaemic control in patients with type 2 diabetes mellitus in Switzerland: A national cross-sectional survey

Abstract

AIMS: We investigated contemporary diabetes care, quality of glycaemic control, and progression of obesity in patients with diabetes mellitus in different cultural regions within Switzerland. METHODS: Overall, 1121 patients treated for type 2 diabetes mellitus by 134 general practitioners were enrolled in this representative, national, crosssectional survey and were followed retrospectively from the start of diabetes treatment. Patients were classified into four cultural regions; the German, French, Italian and Romansh speaking parts of Switzerland. RESULTS: During 5.5 ± 5.1 years of diabetes treatment (retrospective survey), mean HbA1c decreased from 8.28 ± 2.01% to 7.03 ± 1.24%, fasting glucose decreased from 9.97 ± 3.86 to 7.52 ± 2.23 mmol/l, and BMI decreased from 30.2 ± 5.5 to 29.8 ± 5.6 kg/m2 (p <0.001 for all parameters). Insulin therapy was associated with a larger improvement of mean HbA1c (-1.66 ± 2.33% vs. -1.15 ± 1.91%, p = 0.001) and an increase in BMI (+0.36 ± 2.92 vs. -0.63 ± 2.60 kg/m2, p <0.001). At the time when the cross-sectional survey was conducted, the mean HbA1c and fasting glucose were higher in the Italian part compared to other regions (7.72 ± 1.60% and 9.03 ± 2.49 mmol/l, respectively, p <0.001), and lower in the German part (6.89 ± 1.02% and 7.25 ± 2.02 mmol/l, respectively, p <0.001). In comparison to other regions, biguanides were more often used in the French part (86.1% versus 75.7%), insulin secretagogues in the Italian part (69.9% versus 37.8%), thiazolidinedions in the Romansh part (34.1% versus 17.8%), and insulin was more often used in the German part of Switzerland (27.0% versus 17.1%) (p <0.01 for all parameters). CONCLUSIONS: Efforts to identify regional-cultural differences and attempts to overcome associated potential barriers should be emphasised in any health care system when aiming for better diabetic patient care.