Prevalence, awareness and treatment of type 2 diabetes mellitus in Switzerland: the CoLaus study

Aims To assess the prevalence, awareness and treatment levels of Type 2 diabetes in a Swiss city. Methods Population-based cross-sectional study of 6181 subjects (3246 women) aged 3575 years living in Lausanne, Switzerland. Type 2 diabetes was defined as fasting plasma glucose = 7 mmol/l and/or oral hypoglycaemic treatment and/or insulin. Results Total prevalence of Type 2 diabetes was 6.3% (95% confidence interval: 5.77.0%), higher in men (9.1%) than in women (3.8%, P < 0.001) and increased with age. Two-thirds (65.3%; 60.470.0%) of participants with Type 2 diabetes were aware of their status and among those aware 86.0% (81.590.3%) were treated. Treatment was more frequent in men (91.3%) than in women (75.9%, P < 0.001). Two-thirds of those treated for Type 2 diabetes were on monotherapy. Biguanides were prescribed in 65.0% of Type 2 diabetes patients and represented 48% of all antidiabetic drugs. Multivariable analysis showed male gender, increasing age, waist or BMI to be positively associated with prevalence of Type 2 diabetes, while leisure-time physical activity and alcohol consumption were negatively associated. Among participants presenting with Type 2 diabetes, increasing age was positively associated with awareness of Type 2 diabetes. Among subjects diagnosed with Type 2 diabetes, male gender and increasing age were positively associated with treatment. Conclusion Prevalence of Type 2 diabetes in Switzerland is estimated to be between 5.7% and 7.0%. Two-thirds of patients with Type 2 diabetes are aware of their status, and over three quarters of those aware are treated.