SAN ANTONIO – The state of Montana is proof that the success of the landmark Diabetes Prevention Program can be translated to the real world.
The Diabetes Prevention Program, funded by the National Institutes of Health, randomized 3,234 nondiabetic individuals with elevated glucose levels to placebo, metformin (850 mg twice daily), or a lifestyle modification program with the goals of at least a 7% weight loss and at least 150 minutes of physical activity per week. After an average follow-up of 2.8 years, the lifestyle intervention reduced the progression to diabetes by 58% compared with placebo, while metformin lowered the risk by 31% (N. Engl. J. Med. 2002;346:393-403).
In Montana, four existing diabetes prevention programs that were staffed by certified diabetes educators, registered dieticians, cardiac rehabilitation specialists, exercise specialists, and physical therapists were selected to deliver Montana’s lifestyle coaching.
Staff at all sites – another four were added in 2009 – attended a 2-day training in the DPP program that was adapted for group sessions, in contrast to the individual sessions delivered in the original trial, according to Karl K. Vanderwood, M.P.H., of the Montana Diabetes Project.
The weight loss and exercise goals were the same as in the DPP. A total of 16 classes were delivered over 16 weeks, compared with the DPP, where 16 sessions occurred over 16-24 weeks. Participants also had the option of attending twice-weekly physical activity sessions. Between 8 and 30 participants attended the classes, and there was no variation in outcome by group size, said Mr. Vanderwood.
Eligible adults were referred by primary care providers. Participants had to have a body mass index of 25 kg/m2 or greater, along with one or more other risk factors for diabetes or cardiovascular disease such as a diagnosis of impaired glucose tolerance (IGT) or impaired fasting glucose (IFG), hypertension, dyslipidemia, or a history of gestational diabetes mellitus. (Unlike the DPP, a strict diagnosis of IGT or IFG was not required.)
Of 1,003 recruited, 801 completed the initial 16-week program. Of those, 563 were followed up again at 10 months. At 16 weeks, there were significant reductions from baseline in weight (99 to 92 kg, a 7% drop), systolic blood pressure (134 to 127 mm Hg, a 5% drop), diastolic blood pressure (82 to 79 mm Hg, a 4% drop), HDL cholesterol (49 to 46 mg/dL, a 6% drop), LDL cholesterol (125 to 115 mg/dL, an 8% drop), and fasting blood glucose (102 to 97 mg/dL, a 5% drop).
Weight reduction often brings an initial drop in HDL cholesterol, which tends to level out with weight maintenance, Mr. Vanderwood noted. Indeed, at the 10-month follow-up, the mean HDL cholesterol had risen to 51 mg/dL, a statistically significant increase from baseline. At 10 months, the improvements in systolic and diastolic blood pressure, LDL cholesterol, and fasting blood glucose remained statistically different from baseline. Mean weight was 90 kg, from 97 kg at baseline among the 563 participants analyzed. This did not achieve statistical significance.
At baseline, 70% of participants had three or more cardiometabolic risk factors, whereas by 10 months more than half had just 0-2 such risk factors, he added.
These outcomes are similar to those seen in the DPP. Since the only evaluation after 10 months has been a mailed survey, there are no conclusive data regarding progression to diabetes. However, that’s not really the aim of this pilot project, which was designed to see whether a DPP-based program could be implemented in the community, Mr. Vanderwood said in a follow-up interview.
“Our focus is on implementing the DPP and using our resources (money) to do so. Our thought is that it is more important to get people ‘inoculated’ with intervention than to expend time and resources following up on them,” he said, adding that the health department may decide to monitor diabetes conversion rates long term.
An important key to success of the program was that it utilized experienced staff at facilities with established referral mechanisms from community providers. “Health care providers welcomed this project into their community. I think they were jumping for joy to have a place to send these folks,” said certified diabetes educator Marcene K. Butcher, R.D., also of the Montana Diabetes Project.