SOURCE: Suterwala A, Rethorst CD, Carmody TJ, et al. Affect following first exercise session as a predictor of treatment response in depression. J Clin Psychiatry 2016;77:1036-1042.

Although most depressed patients treated with antidepressants note favorable symptom improvement, only about one-third achieve full remission. Selective serotonin reuptake inhibitors are the most common first-line antidepressants used in the United States and, although generally well tolerated, may induce problematic adversities such as sexual dysfunction. Additionally, the response to pharmacotherapy may take several weeks or longer to manifest, during which time clinicians cannot be confident whether any particular antidepressant ultimately will be effective. If the response to a chosen antidepressant treatment turns out to be insufficient, the clinician will have wasted the patient’s time and money, and potentially exposed the patient to unwanted adverse effects.

Exercise has been noted to produce favorable outcomes in depressed patients. Might the early response to exercise predict who would respond favorably over the long term?

Suterwala et al performed a randomized, controlled trial of exercise in depressed patients (n = 126). High-dose exercise (180 minutes/week moderate-vigorous activity) was compared with low-dose activity (45 minutes/week). Exercise was supervised during one session each week for the entire 12-week duration of the trial.

The Positive and Negative Affect Scale (PANAS) was administered to both groups immediately after the very first supervised session in the study’s first week. A favorable PANAS score after the first exercise session proved to be a good predictor of improvement at 12 weeks, as well as likelihood of remission, but only in the high-dose exercise group. We may be better able to capture the potential for beneficial effects of exercise in depression by early identification of responders.