Screening for Type 2 Diabetes: literature review

The review will cover the following aspects; 1. What are we trying to achieve by screening? What interventions would be applied after early diagnosis in asymptomatic people, and what health benefits might be achieved? What harms might result? 2. Consideration of high-risk groups. This will focus mainly on which groups are at high risk of diabetes, but also consider which groups may be at higher risk from the macrovascular complications, principally ischaemic heart disease, of diabetes. Risk would be define din terms of obesity, age, ethnicity, and existing morbidities such as hypertension. 3. Consideration of best test, such as fasting or casual plasma glucose. Screening interval will be considered if data permit. 4. The issue of what to do about lesser degrees of glucose intolerance, such as impaired fasting glucose and impaired glucose tolerance, since inevitably screening would identify people with those, as well as with diabetes. (This was not covered in the commissioning brief, but is important, since it is possible that the number of people with IFG and IGT might considerably exceed the number with diabetes, depending on which test was used.) 5. The costs of different strategies. 6. The cost-effectiveness of screening. The review will include an assessment of the case for screening using the NSC criteria. The review will not cover methods of improving uptake in ethnic or socially disadvantaged groups, since that would be a greater task than is achievable in the time available. Methods and structure. Clinical effectiveness. We would start from the previous review by NJ Wareham, and then review; a) more recent reviews of screening, limited to western countries b) any recent primary studies not included in recent reviews. Cost-effectiveness We would review previous economic studies, and possibly, do some modelling with the data from recent studies, if those differ from the previous review.