SAN DIEGO – The odds of full remission from clinically diagnosed major depression greatly improved in patients with type 2 diabetes who took part in 12-week supervised exercise and cognitive behavioral therapy (CBT). By the end of the study, 96% of the CBT participants no longer met diagnostic criteria for major depression, compared with just 65% of those on usual care, judging from the findings of a new study.
Another approach – a combination treatment of both exercise and CBT therapies – did not show a statistically significant effect on full remission rates but showed improvement in some other areas.
“The interventions significantly improved depression diagnosis and depressive symptom outcomes in this sample,” said study lead author Mary De Groot, Ph.D., speaking at the annual scientific sessions of the American Diabetes Association. She is associate professor of medicine and acting director of the Diabetes Translational Research Center at Indiana University, Bloomington.Dr. De Groot and her colleagues recruited 140 adults – mean age 57 years, 77% female, 71% white, 52% married – who had a diagnosis of both type 2 diabetes and diagnosed clinical depression. They came from three states and had various levels of income and educational background.
The researchers randomly assigned the participants to usual care, 12 weeks of exercise with a personal trainer, 10 individual CBT sessions, or a combination of both exercise and CBT therapies. There were 34-36 participants in each group.
The researchers found improvements in depressive symptoms (P less than .05); negative automatic thoughts (P less than .03), and diabetes distress (P less than .01) and physical quality of life (P less than .03 for all except P greater than 0.1 for CBT) for all three intervention groups compared with usual care. Diabetes-specific quality of life improved in the exercise and combination groups only (P less than .01).
The researchers calculated odds ratios of full or partial remission as 12.4 (CBT) and 5.8 (exercise) compared to usual care (P less than .03), controlling for changes in antidepressant drugs. However, the odds ratio for combination therapy was 2.3 and not deemed statistically significant (P = .218).
The researchers also examined results in subjects with a baseline hemoglobin A1c of 7% or higher and found evidence linking the exercise therapy to clinically meaningful 0.7% improvements in HbA1c (P less than .04).
It’s also not clear whether the interventions will hold up over the long term.
The National Institutes of Health–National Institute of Diabetes and Digestive and Kidney Diseases funded the study. Dr. De Groot reported no relevant disclosures.