A Study to Investigate the Benefits of the Early Detection and Intensive Treatment of Type 2 Diabetes

Overview

Diabetes is a common chronic condition associated with the risk of heart disease, and eye and kidney damage. Many people are diagnosed with diabetes when they develop symptoms or complications, suggesting that the true onset of disease occurs years earlier. Early detection of diabetes may result in health benefits, but this is not proven. People of South Asian origin are at more risk of having diabetes and of getting the heart disease complications associated with it. The study aims to test whether screening for diabetes is feasible in a South Asian population and to measure the benefits of early detection and intensive treatment. Hypothesis: A program of screening and an intensive multi-factorial intervention for type 2 diabetes is both feasible and cost effective within primary care.

Although diabetes is commonly undiagnosed and many patients have evidence of complications at diagnosis, there is no definitive evidence that early detection improves health outcomes. One of the critical but uncertain factors is the extent to which screening and subsequent treatment reduces cardiovascular risk. Multi-factorial cardiovascular risk reduction in people with prevalent diabetes and microalbuminuria results in a halving of heart disease risk. However, it is not certain whether this result can be generalised to patients without microalbuminuria or those whose disease is screen-detected. The ADDITION study is a collaborative randomised controlled trial of a target-driven intensive multi-factorial approach to cardiovascular risk reduction in patients with screen-detected type 2 diabetes mellitus, aimed at assessing the feasibility of screening in a primary care setting and quantifying the cardiovascular benefits and economic and psychological costs of screening. The study as a whole will have the power to determine whether screening and the intensive multi-factorial intervention results in improved cardiovascular outcomes. The ADDITON-Leicester study will contribute to this collaboration, but which by itself will demonstrate the feasibility of screening and measure the effect of the ADDITION study intervention on modelled cardiovascular risk at 1 year after detection by screening in a population at high risk by virtue of having a high proportion of people from South Asia (Leicester). The study is also assessing the impact of intensive intervention of modelled cardiovascular risk at 1 year. People of South Asian origin are at increased risk of having diabetes and of developing heart disease. The issues of screening are thus particularly relevant to this population. However, all of the populations currently recruited to ADDITION are predominantly Caucasian. The ADDITION-Leicester study will assess the feasibility of systematic screening in a South Asian population, will quantify the effect of intensive treatment in people with screen detected diabetes on modelled cardiovascular risk at 1 year and will assess the economic and psychological costs of screening and intensive treatment. This study population will then contribute to the ADDITION-Europe study, which as a whole is powered to assess the impact of screening and intensive treatment on 5 year cardiovascular outcomes.