People who have symptoms of depression may have an increased risk of having a stroke, according to a new study.
The researchers conducting the study also found that such people were more likely to have a 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 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," said Murphy.
The results of the study are published in the journal Neurology.
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, it said.
INTERSTROKE study is an international, multi-centre case-control study and is the largest international study of risk factors for acute stroke, according to Neurology.
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Of the study participants, 18% of those who had a stroke had symptoms of depression compared to 14% of those who did not have a stroke, the study found.
People with symptoms of depression before stroke had a 46% increased risk of stroke compared to those with no symptoms of depression, the study said, after adjusting for age, sex, education, physical activity and other lifestyle factors.
The study further found that 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.
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, the study found.
The scientists also found that 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," said Murphy.
"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," said Murphy.
Of the 26,877 participants, more than 13,000 had had a stroke. The study matched them with more than 13,000 people who had not experienced a stroke but were similar in their age, sex, racial or ethnic identity.
Participants were reported to have an average age of 62.
At the beginning of the study, participants completed questionnaires regarding cardiovascular risk factors, including high blood pressure and diabetes.
The researchers collected information regarding symptoms of depression within the year prior to the study. They had been asked whether they had felt sad, blue, or depressed for two or more consecutive weeks over the past 12 months, according to the study.
A limitation of the study was that the 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.