CLINICAL QUESTION: Is a supervised group exercise program effective in treating depression in older adults?
BACKGROUND: Major depressive disorder (MDD) occurs in up to 18% of older adults1 and is a major cause of morbidity, decreased quality of life, and mortality in this age group. Effective treatment options include psychotherapy and the use of antidepressants.2 Aerobic exercise is an effective therapeutic option in younger adults with MDD, but this option has not been well studied in the elderly.
POPULATION STUDIED: Older adults aged 50 to 77 years were recruited from the community who met Diagnostic and Statistical Manual of Mental Disorders, 4th edition criteria for MDD. Of the 604 subjects initially screened, 156 met the inclusion criteria and were randomly assigned to 1 of the 3 treatment groups. The groups were similar in mean age (57 years), race, sex, marital status, history of recurrent depression, and severity of depression.
STUDY DESIGN AND VALIDITY: This was a randomized controlled trial. After an initial assessment by clinical psychologists, eligible subjects were randomized to exercise (supervised group aerobics consisting of walking or jogging for 30 minutes 3 times a week at an intensity to achieve 70% to 85% of maximum heart rate); antidepressant therapy (sertraline 50 mg titrated up to 200 mg a day as needed to achieve effectiveness); or a combination of exercise and antidepressants. Randomization was stratified on the basis of severity of depression as determined by the Hamilton Rating Scale for Depression (HAM-D). These patients were assessed periodically for 16 weeks by investigators who were blinded to the treatment allocation.
OUTCOMES MEASURED: Treatment response was measured by the HAM-D and the Beck Depression Inventory at weeks 1, 2, 3, 4, 6, 8, and 12. Aerobic capacity was measured at the beginning and end of the trial using a symptom-limited graded exercise treadmill test.
RESULTS: At the end of the 4-month trial, 60% to 69% of the subjects were no longer depressed; there was no statistical difference among the 3 groups. Patients receiving drug therapy responded faster, though those in the exercise group caught up by the end of the trial. Of note, 15% of the medication-only group and 26% of the exercise group did not complete the study because of adverse effects or inability to follow therapy. The patients in the exercise programs also showed significant improvements in their aerobic capacity (mean = 11% increase) compared with those in the medication-only group.
Supervised group exercise (walking or jogging) at 70% to 85% of maximal aerobic intensity was as effective as sertraline in treating MDD. Sertraline worked faster, however, and more patients stayed with it than with the exercise program. For older adults with MDD who have contraindications to drug therapy or who wish to try alternative approaches, group aerobic exercise is effective.