Depressed women face raised stroke risk
MedWire News: Depression is linked to a moderately increased risk for stroke in women, study findings show.
The analysis of data from the Women's Heart Study found that a history of depression and use of antidepressant medication were each associated with an increased risk for stroke, leading the researchers to call for more study of preventive strategies in this group.
Kathryn Rexrode (Brigham and Women's Hospital, Boston, Massachusetts, USA) and team obtained information on 80,574 women aged 54-79 years who were enrolled in the Nurses' Health Study, all of whom were free of stroke at baseline. The women were followed-up for 6 years, during which time there were 1033 confirmed or probable strokes.
A surprisingly high proportion of women - 22.3% - were suffering from depression at baseline, report Rexrode and co-authors Stroke journal. Compared with their non-depressed counterparts, depressed women were more likely to be single, smokers, and less physically active.
They were also slightly younger, had a higher body mass index, and had more comorbid conditions such as hypertension, diabetes, and heart disease.
"Depression can prevent individuals from controlling other medical problems such as diabetes and hypertension, from taking medications regularly or pursuing other healthy lifestyle measures such as exercise," said Rexrode, in a press release accompanying the study. "All these factors could contribute to increased risk."
Nevertheless, after adjusting for a raft of baseline differences and other potential confounders, depressed women were 29% more likely to suffer a stroke than non-depressed women (hazard ratio [HR]=1.29). The excess risk associated with depression was seen for hemorrhagic, ischemic, and unknown subtypes of stroke, with HRs of 1.20, 1.11, and 1.63, respectively.
The use of antidepressant medication was also associated with an increased risk for stroke, with an HR of 1.39 in women with diagnosed depression and 1.31 in women with no diagnosed depression, as compared with non-use of such medication.
Finally, there appeared to be a graded association between depression and stroke risk, with a HR of 1.41 in women with current depression and 1.23 in those with past depression.
Discussing their findings, the researchers propose various biologic mechanisms by which depression might raise stroke risk, including neuroendocrine, immunologic/inflammatory, and vascular pathways.
"We cannot infer cause or fully exclude the possibility that the results could be explained by other unmeasured unknown factors," admitted An Pan (Harvard School of Public Health, Boston), co-author of the study. "Although the underlying mechanisms remain unclear, recognizing that depressed women may be at a higher risk of stroke merits additional research into preventive strategies in this group."
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By Joanna Lyford