Exercise, healthy diet provide modest improvement in diabetes

A diet plan coupled with a high amount and intensity of exercise allowed certain patients with diabetes to scale back on glucose-lowering medications use, but that intervention only led to modest reduction in blood glucose levels, according to findings published in JAMA.

“Whereas medication is effective in lowering HbA1c in patients with type 2 diabetes, it is also associated with potential adverse drug interactions, discomforts, increased economic costs and decreased quality of life,” Mette Yun Johansen, MSc, of the Centre of Inflammation and Metabolism at the University of Copenhagen in Denmark, and colleagues wrote. “Therefore, lifestyle interventions are needed that are able to maintain glycemic control to at least the same extent as medication.”

To test their hypothesis that exercise and diet can produce the same effect as medical care in patients with type 2 diabetes, researchers randomly placed 98 such patients who had received that diagnosis less than 10 years ago into either a lifestyle group or standard care group. The mean age of the participants was 54.6 years, and 47 of them were women.

All patients engaged in one-on-one counseling and medical therapy, but the 64 patients in the lifestyle group also took part in five to six weekly aerobic training sessions, each lasting between 30 and 60 minutes, and of which half the sessions also included resistance training. Lifestyle participants also received dietary plans intended to get their BMI to 25 kg/m² or less. All participants were followed up for up to 1 year to see what changes occurred in their HbA1c levels. Equivalence was defined by a CI margin of ± 0.4% based on the intention-to-treat population, and superiority analysis was conducted on the secondary outcome reductions in glucose-lowering medication.

Researchers found that at follow-up, reduction in glucose-lowering medications occurred in 47 of those in the lifestyle group and nine of those in the standard care group (difference, 47.1 percentage points; 95% CI, 28.6-65.3). However, the mean HbA1c level changed from 6.65% to 6.34% in the lifestyle group and from 6.74% to 6.66% in the standard care group (mean between-group difference in change of 0.26%; 95% CI, 0.52 to 0.01). There were 32 adverse events (most commonly mild hypoglycemia and musculoskeletal discomfort or pain) in the lifestyle group and five in the standard care group.

“[The] change in glycemic control ... did not reach the criterion for equivalence, but was in a direction consistent with benefit,” Johansen and colleagues wrote. “Further research is needed to assess superiority, as well as generalizability and durability of findings.” – by Janel Miller

Disclosures: Johansen reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.