The development of type 2 diabetes (DM) was reversed in four years in almost 60% of subjects with impaired glucose tolerance after receiving advice on nutrition and exercise 1. There were more than 500 subjects. The target amount of physical activity was four times per week. Average weight loss in the intensive care group was almost 4 kg.
In the follow-up study of Finnish Diabetes Prevention Study (DPS) 3, the participants who were still free of diabetes after 4 years were further followed up for a median of 3 years. The corresponding incidence rates of DM were 4.6 in the intervention and 7.2 in the control group, indicating 36% reduction in relative risk. During the total follow-up of 13 years 4, the adjusted HR for diabetes (intervention group vs control group) was 0.614 (95% CI 0.478 to 0.789). The former intervention group participants sustained lower absolute levels of body weight, fasting and 2 h plasma glucose and a healthier diet. Adherence to lifestyle changes during the intervention period predicted greater risk reduction during the total follow-up.
The results were very similar in a study conducted in the United States 2. A lifestyle-modification program (goals: at least a 7% weight loss and at least 150 minutes of physical activity per week) was compared with metformin (850 mg twice daily) and with placebo. The incidence of diabetes was 11.0, 7.8, and 4.8 cases per 100 person-years in the placebo, metformin, and lifestyle groups, respectively. The lifestyle intervention reduced the incidence by 58% (95% CI, 48 to 66%) and metformin by 31% (95% CI, 17 to 43%), as compared with placebo; the lifestyle intervention was significantly more effective than metformin. To prevent one case of diabetes during a period of three years, 6.9 persons would have to participate in the lifestyle-intervention program, and 13.9 would have to receive metformin.
In the follow-up study of DPP 5, all 3 groups were offered group-implemented lifestyle intervention. Metformin treatment was continued in the original metformin group. During the 10-year follow-up since randomisation to DPP, the original lifestyle group lost, then partly regained weight. The modest weight loss with metformin was maintained. Diabetes incidence rates in this follow-up study were similar between treatment groups: 5.9 per 100 person-years (5.1-6.8) for lifestyle, 4.9 (4.2-5.7) for metformin, and 5.6 (4.8-6.5) for placebo. Diabetes incidence in the 10 years since DPP randomisation was reduced by 34% (24-42) in the lifestyle group and 18% (7-28) in the metformin group compared with placebo.
In a cluster randomised trial 6 33 clinics in Da Qing, China, were randomly assigned to either be a control clinic or provide one of 3 interventions (diet, exercise, or diet plus exercise) for 6 years for 577 adults with impaired glucose tolerance (438 in intervention group and 138 in the control group). After 30 years of follow-up, 540 (94%) of 576 participants were assessed for outcomes (135 in the control group, 405 in the intervention group). Compared with control, the combined intervention group had a median delay in diabetes onset of 3.96 years (95% CI 1.25 to 6.67; p=0.0042), fewer cardiovascular disease events (hazard ratio 0.74, 95% CI 0.59 to 0.92; p=0.0060), a lower incidence of microvascular complications (0.65, 0.45. to 0.95; p=0.025), fewer cardiovascular deaths (0.67, 0.8 to 0.94; p=0.022), fewer all-cause deaths (0.74, 0.61 to 0.89; p=0.0015), and an average increase in life expectancy of 1.44 years (95% CI 0.20 to 2.68; p=0.023).
The following decision support rules contain links to this evidence summary:
The following decision support rules contain links to this evidence summary:
Primary/Secondary Keywords