People who have symptoms of depression may have an increased risk of having a stroke, according to a study published in the online issue of Neurology, the medical journal of the American Academy of Neurology. Researchers also found that people with symptoms of depression were more likely to have worse recovery after a stroke.
“Depression affects people around the world and can have a wide range of impacts across a person’s life,” said study author Robert P. Murphy, MBBS, of the University of Galway in Ireland. "Our study provides a broad picture of depression and its link to risk of stroke by looking at a number of factors including participants’ symptoms, life choices and antidepressant use. Our results show depressive symptoms were linked to increased stroke risk and the risk was similar across different age groups and around the world.”
The study involved 26,877 adults from the INTERSTROKE study and included people from 32 countries across Europe, Asia, North and South America, the Middle East and Africa. Participants had an average age of 62. Of participants, more than 13,000 had a stroke. They were matched with more than 13,000 people who had not experienced a stroke but were similar in their age, sex, race or ethnic identity.
Participants completed questionnaires at the beginning of the study regarding cardiovascular risk factors, including high blood pressure and diabetes. Researchers collected information regarding symptoms of depression within the year prior to the study. They were asked whether they had felt sad, blue, or depressed for two or more consecutive weeks during the past 12 months.
Of study participants, 18% of those who had a stroke had symptoms of depression compared to 14% of those who did not have a stroke. After adjusting for age, sex, education, physical activity and other lifestyle factors, people with symptoms of depression before stroke had a 46% increased risk of stroke compared to those with no symptoms of depression.
The more symptoms participants had, the higher their risk of stroke. Participants who reported five or more symptoms of depression had a 54% higher risk of stroke than those with no symptoms, while those who reported three to four symptoms of depression and those who reported one or two symptoms of depression had 58% and 35% higher risk, respectively.
While people with symptoms of depression were not more likely to have more severe strokes, they were more likely to have worse outcomes one month after the stroke than those without symptoms of depression.
“In this study we gained deeper insights into how depressive symptoms can contribute to stroke," Murphy added. "Our results show that symptoms of depression can have an impact on mental health, but also increase the risk of stroke. Physicians should be looking for these symptoms of depression and can use this information to help guide health initiatives focused on stroke prevention.”
A limitation of the study was that participants filled out questionnaires about symptoms of depression only at the start of the study, so the effects of depression over time could not be measured.