Evidence of a link is growing stronger

A few studies have suggested a link between depression and stroke, and now a recent meta-analysis offers strong evidence supporting the connection. Results of the meta-analysis, published in the Journal of the American Medical Association in 2011, found that depression was associated with a significantly increased risk of stroke and stroke-related death. People with depression had a 45 percent greater risk of stroke and a 55 percent greater risk of dying of a stroke compared with people who weren't depressed.

Analyzing data from 28 studies that included more than 300,000 patients, the researchers estimated that nearly 4 percent of stroke cases in the United States each year could be attributed to depression. Beyond these statistics, what's notable is that the researchers made a point of suggesting that depression is a "modifiable" risk factor for stroke, although the analysis didn't have data about whether treatment for depression could lower the risk of stroke. (Depression has also been closely associated with other disorders that often coexist with stroke: diabetes, hypertension and cardiovascular disease.)

Depression's physical impact

The meta-analysis found depression linked only to ischemic stroke, the more common type, which results from blockage in a blood vessel providing blood to the brain. There was no increased risk of hemorrhagic stroke found in depressed patients; this type of stroke occurs when an artery in the brain tears or ruptures and blood leaks into the surrounding tissue.

Depression may contribute to ischemic stroke in several ways, according to the research. People who are depressed are more likely to have an unhealthy lifestyle because of smoking, a poor diet and lack of exercise. They may also be lax in taking medication for high blood pressure or diabetes, both of which are high risk factors for stroke.

Changes in body chemistry

Another possibility is that chemical changes in the body caused by depression could influence stroke risk. These include an increase in C-reactive protein, a marker for inflammation in the blood vessels, yet another stroke risk factor.

The analysis also found a link between use of antidepressant medication and stroke risk. However, the researchers cautioned that most of the studies they analyzed did not include information on antidepressant use, and when they did, information about dose and duration was lacking. More study is needed to determine whether these medications actually do contribute to stroke risk, so stopping medication was not recommended.

Are you depressed?

Regardless of your stroke risk, it's important to seek medical help if you are experiencing symptoms of depression. Primary symptoms are

  • persistent low or sad mood,
  • decreased or absent interest in almost all activities,
  • or
  • a loss of self-confidence and
  • feelings of guilt, worthlessness and helplessness.

Other symptoms may include:

  • Sleep problems—insomnia, early-morning waking or oversleeping nearly every day
  • Decreased energy or fatigue
  • Noticeable changes in appetite and weight (significant weight loss or gain)
  • Inability to concentrate or think, or indecisiveness
  • Physical symptoms of restlessness or being physically slowed down
  • Recurrent thoughts of death or suicide, or a suicide attempt

If you're diagnosed with depression, your doctor will help you determine the best course of treatment. Antidepressant medication is often the recommended initial treatment choice for people with mild to moderate depression or severe major depression. Another option is psychotherapy, alone or in combination with medication.

In addition, lifestyle measures—especially regular exercise, getting enough sleep and eating a healthy diet—play a role in improving mood and self-image.

Publication Review By: Lawrence Appel, M.D., and Rafael H. Llinas, M.D.

Published: 16 Jul 2013

Last Modified: 16 Jul 2013