Lifestyle changes can prevent the onset of type 2 diabetes

Lifestyle changes may prevent the onset of type 2 diabetes mellitus in persons with a higher risk of developing the disease (primary prevention). Examples are reducing the intake of total fat and saturated fat, increasing the intake of fibre and increasing physical activity, as well as losing excessive weight. Evidence for the preventive effect of lifestyle changes comes from several intervention studies, such as the 'Diabetes Prevention Program' in the United States and the Finnish 'Diabetes Prevention Study' (Knowler et al., 2002; Tuomilehto et al., 2001).

The objective of the EU co-funded project Diabetes in Europe is to implement and evaluate a lifestyle intervention programme in different European countries to prevent type 2 diabetes in high-risk individuals. The project started in spring 2005 and has a duration of 3 years.

Screening helps in early detection and prevention of complications

As many people are unaware of their diabetes, they often start to show evidence of organ or tissue damage before diabetes is diagnosed and treated. Screening is aimed at early detection and hence at earlier treatment of previously undiagnosed type 2 diabetes to prevent development of complications (secondary prevention). However, evidence from randomized controlled trials on the effectiveness of screening is insufficient (WHO, 2003c). The overall aims of the ADDITION study in the UK, Denmark and the Netherlands are to evaluate whether screening for prevalent undiagnosed type 2 diabetes is feasible, and whether subsequent intensive treatment of diabetes and associated risk factors, is feasible and beneficial. This study does not answer the question whether screening is effective or not, because a control group is lacking (Lauritzen et al., 2000).

Prevention of complications by regulating blood glucose concentration

The primary aim of diabetes treatment is to regulate glucose concentration in the blood and prevent micro- and macrovascular complications that are caused by raised blood glucose levels (tertiary prevention). Intervention trials such as the United Kingdom Prospective Diabetes Study have shown that the combined treatment of hyperglycaemia, hypertension and hyperlipidemia is more effective in reducing the risk for macrovascular complications than treating hyperglycaemia alone (UKPDS-group, 1998a; UKPDS-group, 1998b). Hyperglycaemia in type 1 diabetes is treated by injections of insulin and a healthy diet. Hyperglycaemia in type 2 diabetes is treated by a healthy diet and oral antidiabetics. Some people with type 2 diabetes also need insulin injections.

Preventive care practices counteract worsening of complications

Preventive care practices can counteract worsening of complications. Examples are laser therapy for diabetic eye disease, foot care programs for diabetic feet and blood pressure lowering drugs to treat diabetic kidney disease (CDC, 2005c).

A new WHO review on the Prevention of diabetes and its complications will be available in the second half of 2008.