Long-term results from the Diabetes Prevention Program found that individuals who are active and perform moderate exercise regularly have a better chance to avoid developing diabetes — perhaps even more so than concentrating on weight loss, researchers suggested here.
Regardless of treatment group — lifestyle based or medically based — over an average of 11.9 years there was a 2% decrease in diabetes incidence for each 6-MET hours/week increase in physical activity, said Andrea Kriska, PhD, professor of epidemiology at the University of Pittsburgh. That is the equivalent of about 1.5 hours more of a brisk walk a week more than the average activity, and was statistically significant (HR .98, CI 0.97-0.99P<0.0001), she reported.
“Until now, the importance of physical activity in preventing diabetes development in the Diabetes Prevention Program was thought to be due to its role in achieving weight loss and weight maintenance; however, it was not considered a strong key factor alone,” Kriska said at the annual meeting of the American Diabetes Association.
In commenting at a press conference, she added, “It is important for health care professionals to look beyond their high-risk patients’ weight and also consider their physical activity levels when discussing strategies to prevent progression to Type 2 diabetes.”
In the study, Kriska and her colleagues followed outcomes of a subgroup of 1,793 participants who fulfilled criteria for being diagnosed as pre-diabetic. Of that group, 589 had been assigned to lifestyle management; 599 patients were prescribed metformin; 605 patients were given placebo.
The protective effect of physical activity was observed the most in patients who, at baseline, said they performed less than 150 minutes a week of physical activity. Among these patients who upped their activity game, there was a 5% decrease in risk of progressing to diabetes (95% CI 0.93, 0.97, P<0.0001), Kriska reported.
“The study results also suggest that the lower Type 2 diabetes development across the entire study for those that took part in the lifestyle arm of the study many be partially explained by improvement in physical activity levels in addition to weight loss,” Kriska said.
“Maintaining your patients adequate physical activity levels is very important in diabetes progression, regardless of any weight changes,” she said. “Both physical activity and weight intervention need to be encouraged and supported.”
In commenting on the study, press conference moderator Ann Albright, PhD, director of the division of diabetes translation at the National Center for Chronic Disease Prevention and Health Promotion, Atlanta, said “You can see that with some of these interventions, we have the potential to reduce the number of new cases of diabetes.” She said the interventions have to be “practical and implementable.”
About 45% of the Diabetes Prevention Program were ethnically diverse, the researchers reported. The participant were 25 years of age or older and were recruited from 27 sites in the United States. The participants who were assigned to the lifestyle arm were given an intensive behavioral intervention consisting of nutrition and physical activity with the two goals of being physically active for a minimum of 150 minutes per week and achieving a weight loss of 7%. All other participants were also give a modified lifestyle intervention pep talk.
The interviewer-administered Modifiable Activity Questionnaire was used to track physical activity yearly; diabetes status was determined by annual oral glucose tolerance and semi-annual fasting plasma glucose tests.
Kriska noted, “Although the Diabetes Prevention Program study was not designed to examine the separate effects of physical activity or weight on diabetes incidence, post hoc analyses indicate that physical activity levels over the entire program and its Outcomes Study were inversely related to incident diabetes when controlled for weight and other important covariates. These results suggest that the lower cumulative diabetes incidence found in the lifestyle group across the entire study was partially explained by physical activity differences.”