Objective: The objective of this study was to estimate the annual rate of diagnosis of new cases of diabetes mellitus in England and Wales, and the number of new cases in each year.
Study design: Cohort study.
Method: Analysis of electronic patient records from the General Practice Research Database, using 208 general practices with a total list size of 1.3 million patients.
Results: We estimate that the national rate of diagnosis of new cases of diabetes in England and Wales was 17.5 [95% confidence intervals (CI) 16.6--18.4] per 10,000 person-years in 1994 and 22.1 (95%CI 21.2--23.0) per 10,000 person-years in 1998. We estimate that there were 87,642 new cases of diabetes mellitus in England and Wales in 1994 and 111,345 in 1998.
Conclusions: We estimate that the rate at which new cases of diabetes were diagnosed rose by about 26% in England and Wales from 1994 to 1998. This conclusion was unchanged when we took account of the ageing of the national populations between the beginning and end of the study period. We estimate that the number of new cases of diabetes diagnosed each year in England and Wales also increased by one-quarter over the same period. If the number of cases and the rate at which they are diagnosed continues to increase, this will need to be considered by those planning services for people with diabetes.