People with depression know that it can be frustratingly persistent, requiring various kinds of treatment, often more than once. Now, a new study suggests that people with long-term depression face another possible challenge – a higher risk of stroke.
The research, published in the Journal of the American Heart Association, not only showed a doubled risk of stroke for middle-aged adults with depression, but that reducing its symptoms might not reduce the elevated risk immediately. So as the study’s lead author said in a news release from the heart association, “Our findings suggest that depression may increase stroke risk over the long term.”
Clinical depression is diagnosed by many factors including severity, duration, persistence and recurrence. People with more severe depressive disorders often have symptoms such as suicidal preoccupations and grave impairments such as an inability to concentrate and hold down a job. Generally, the problem lasts more than two weeks.
Data for the recent study was collected from 16,178 participants 50 years 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 from 1998-2010. During that period, 1,192 strokes were documented.
Compared to study subjects who did not have symptoms of depression in their interviews:
- 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% higher stroke risk.
The researchers didn’t analyze whether depressive symptoms diminished because people got treatment or for some other reason, but they did find that even if treatment had been effective, it might not have immediate benefits in terms of reducing the risk of stroke.
The research also suggested that diminished depression might have a stronger effect on women than men.
A key finding was that if the onset of depression had occurred recently – that is, it wasn’t a long-term condition – the depression wasn’t associated with higher stroke risk.
Because sometimes people believe – and sometimes our culture encourages them to believe – that being depressed is somehow their fault, or that if only they were stronger it would go away, the study might give them and their loved ones another reason to treat the condition; it might help them understand that it’s a serious medical condition, especially if it’s persistent.
In addition to the risk of suicide, previous research has shown an association between depression and an increased risk of high blood pressure, problems with the autonomic nervous system (which controls unconscious bodily functions, including breathing, heartbeat and digestion) and increased inflammatory responses. Depression might trigger vascular problems, including infection or atrial fibrillation (irregular, often rapid heart rate that can cause poor blood flow throughout the body). Also, depressed people are more likely to smoke and be less physically active.
Another researcher involved with the study observed that “Although we now know that depression strongly predicts stroke on par with many other major stroke risk factors, we still need research to understand exactly why this link occurs and whether we can potentially reduce stroke risk by treating depression.”
And we – the medical community and society at large – still need to treat depression as the serious condition it is, because it’s life-threatening on several levels. The good news is that we’re getting there – the Affordable Care Act requires most individual and small employer health insurance plans, including those offered on the government marketplace, to cover mental services.
And most health plans must cover preventive services, including depression screening for adults and behavioral assessments for children, at no additional cost. As of 2014, most plans cannot deny coverage to someone or charge someone more because of pre-existing health conditions, including mental illnesses.