Methods: Using The Health Improvement Network database, we identified patients with type-1 or type-2 diabetes who were 10-79 years between 1996 and 2005. Prevalent cases (n=49999) were separated from incident cases (n=42642;type-1=1256, type-2=41386). Data were collected on treatment patterns in incident cases, and on BMI in prevalent and incident cases.

Results: Diabetes prevalence increased from 2.8% in 1996 to 4.3% in 2005. Incidence of diabetes in the UK increased from 2.71 (2.58-2.85)/1000 person-years in 1996 to 4.42 (4.32-4.53)/1000 person-years in 2005. Incidence of type-1 diabetes remained relatively constant throughout the study period; however, the incidence of type-2 diabetes increased from 2.60 (2.47-2.74)/1000 person-years in 1996 to 4.31 (4.21-4.42)/1000 person-years in 2005. Between 1996 and 2005, the proportion of individuals newly diagnosed with type-2 diabetes that were obese increased from 46% to 56%. Treatment with metformin increased across the study period, while treatment with sulfonylureas decreased.

Conclusions: The prevalence and incidence of type-2 diabetes have increased in the UK over the past decade that might be primarily explained by the changes in obesity prevalence. Also, there was a change in drug treatment pattern from sulfonylureas to metformin.