Objective: To investigate one-year outcomes of a national diabetes prevention program in Finland.

Research Design and Methods: Altogether 10,149 individuals at high risk for diabetes were identified by the Finnish Diabetes Risk Score (FINDRISC; scoring 15 points or more), by a history of impaired fasting glucose (IFG) or impaired glucose tolerance (IGT), cardiovascular disease or gestational diabetes in 400 primary health care centers. One-year follow-up data were available on 2,798 participants who were non-diabetic at baseline (919 men/1879 women, mean age 56.0±9.9/54.0±10.7 years, mean body mass index 30.9±4.6/31.6±5.4 kg/m²).

Results: The incidence of diabetes was 2.0% and 1.2% in men and women with normal glucose tolerance at baseline, 13.5% and 7.4% in IFG, and 16.1% and 11.3% in IGT, respectively. Altogether 17.5% of the subjects lost 5% or more weight with no gender difference. The relative risk of diabetes was 0.31 (95% Confidence interval, CI 0.16-0.59) in the group who lost 5% or more weight, 0.72 (95% CI 0.46-1.13) in the group who lost 2.5-4.9% weight and 1.10 (95% CI 0.77-1.58) in the group who gained 2.5% or more compared with the group who maintained weight.

Conclusions: The FIN-D2D was the first national effort to implement the prevention of diabetes in a primary health care setting. Methods for recruiting high-risk subjects were simple and easy to use. Moderate weight loss in this very high risk group was especially effective in reducing risk of diabetes among those participating in the program.