Increased physical activity may reduce depressive episodes by 17%

Karmel Choi

Among people with a genetic predisposition for depression, 4 additional hours of physical activity may reduce the odds of incident depression by 17%, according to results of a biobank cohort study published in Depression & Anxiety.

“Depression runs in families and has a strong genetic component, and patients with these risk factors may believe there is little they can do to avoid becoming depressed,” Karmel Choi, PhD, clinical and research fellow at the Massachusetts General Hospital and the Harvard T.H. Chan School of Public Health, told Healio Psychiatry. “Our findings suggest otherwise. We saw that being active still makes a difference regardless of genetic risk. This study may help inform the discussion between patients and their health care provider about what pre-existing risk factors they have on board and, importantly, what they can do about it.”

Choi and colleagues analyzed the longitudinal Partners Healthcare Biobank, which integrated genomic data for nearly 8,000 individuals of European ancestry with lifestyle survey responses — including some on physical activity — and high-dimensional electronic health records. From this data, they identified individuals with incident episodes of depression and determined genetic risk scores based on large-scale genome-wide association results for major depression.

The researchers found that every 1 standard deviation (SD) increase in physical activity was associated with a reduced odds of incident depression among individuals at low (adjusted OR = 0.62 per 1 SD increase in activity; 95% CI, 0.47-0.8), intermediate (aOR = 0.89 per 1 SD increase in activity; 95% CI, 0.79-0.99) and high polygenic risk (aOR = 0.82 per 1 SD increase in activity; 95% CI, 0.68-0.98).

Both high-intensity forms of activity, including aerobic exercise or exercise machines, as well as lower-intensity forms, including yoga and stretching, were associated with decreased odds of depression, according to the researchers. Each added 4-hour block of activity per week was linked to an overall 17% reduction in odds of a new episode of depression.

“We were surprised to see that physical activity protected against new episodes of depression, even for people who had already experienced depression in the past,” Choi said. “Because past depression is a strong predictor of later depression, this gives us even more evidence that physical activity may be a powerful tool for beating the odds against future depression.” – by Joe Gramigna

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