Aims To determine the effectiveness of a 2.5-year lifestyle intervention for Type 2 diabetes prevention in Dutch general practice compared with usual care. Methods A randomized controlled trial of 925 individuals at high risk for Type 2 diabetes (FINDRISC-score = 13) in 14 general practices in the Netherlands. Intervention consisted of lifestyle counselling from the nurse practitioner and the general practitioner. Usual care consisted of oral and written information at the start of the study. Study groups were compared over 2.5 years regarding changes in clinical and lifestyle measures. Results Both groups showed modest changes in body weight, glucose concentrations, physical activity and dietary intake [weight: intervention group, -0.8 (5.1) kg, usual care group, -0.4 (4.7) kg, (P = 0.69); fasting plasma glucose: intervention group, -0.17 (0.4) mmol/l, usual care group, -0.10 (0.5) mmol/l, (P = 0.10)]. Differences between groups were significant only for total physical activity and fibre intake. In the intervention group, self-efficacy was significantly higher in individuals successful at losing weight compared with unsuccessful individuals. No significant differences in participant weight loss were found between general practitioners and nurse practitioners with different levels of motivation or self-efficacy. Conclusions Diabetes risk factors could significantly be reduced by lifestyle counselling in Dutch primary care. However, intervention effects above the effects attributable to usual care were modest. Higher participant self-efficacy seemed to facilitate weight loss. Lack of motivation or self-efficacy of professionals did not negatively influence participant guidance.
- impaired glucose-tolerance