Study: Even After Depression Lifts, Sufferers Face Higher Stroke Risk

In case you missed this piece on NPR today, it's worth a listen: Harvard researchers have found that long after the dark symptoms of depression have lifted, those of us who suffered from the disorder have an increased risk of stroke later in life.

Patti Neighmond reports on the new study, published in the Journal of the American Heart Association:

Medical researchers have known for several years that there is some sort of link between long-term depression and an increased risk of stroke. But now scientists are finding that even after such depression eases, the risk of stroke can remain high.

"We thought that once people's depressive symptoms got better their stroke risk would go back down to the same as somebody who'd never been depressed," says epidemiologist Maria Glymour, who led the study when she was at Harvard's T.H. Chan School of Public Health. But that's not what her team found.

Even two years after their chronic depression lifted, Glymour says, a person's risk for stroke was 66 percent higher than it was for someone who had not experienced depression.

The study authors conclude that to mitigate this risk of stroke, depression should be identified and treated early:

This study, in conjunction with other work confirming that depressive symptoms are causally related to stroke risk, suggests that clinicians should seek to identify and treat depressive symptoms as early as possible relative to their onset, before adverse consequences begin to accumulate.

Here's more data from the American Heart Association news release:

Researchers used data from 16,178 participants (ages 50 and older) who had been interviewed as part of the Health and Retirement Study about depressive symptoms, history of stroke, and stroke risk factors every two years in 1998-2010.

The study documented 1,192 strokes over 12 years. Compared to people without depression at either interview:

•People with high depressive symptoms at two consecutive interviews were more than twice as likely to have a first stroke.

•People who had depressive symptoms at the first interview but not the second had a 66 percent higher stroke risk.

Researchers did not evaluate whether depressive symptoms diminished because of treatment or for other reasons; but findings suggest that treatment, even if effective for depression, may not have immediate benefits for stroke risk. Researchers also suggest that diminished depression may have a stronger effect on women than men.