The association of depressive symptoms and stroke is not limited to the poststroke period.

The link between vascular disease and depressive symptoms in the form of poststroke depression is well established. However, the potential for depressive symptoms to be a risk factor for stroke has been studied less. In this analysis, researchers looked at the relationship between depressive symptoms in the 12 months before a stroke and stroke severity and functional outcome one month poststroke. There were 26,877 participants (mean age, 62 years; 40% women) from INTERSTROKE, an international case-control study conducted in 32 countries to examine stroke risk factors, who completed a validated questionnaire about depressive symptoms.

As expected, index stroke cases had a higher rate of conventional vascular risk factors (hypertension, diabetes, hyperlipidaemia) than age-, sex- and location-matched controls. Depressive symptoms were more common in the 12 months preceding stroke in cases than in controls (18% vs 14%). Reporting of depressive symptoms varied among countries, with the highest rates in South America (32%) and lowest rates in China (7%). In adjusted analyses, depressive symptoms were associated with higher rates of both ischaemic stroke and intracerebral haemorrhage. Depressive symptoms were not associated with stroke severity but were associated with worse functional outcomes at one month poststroke (odds of one-point higher score on the modified Rankin Scale, 1.09) and with higher mortality at one month (10% vs 8%).

Comment: This study provides evidence that preceding depressive symptoms are more common in patients with an ischaemic or haemorrhagic stroke than in age- and sex-matched controls. Mechanisms to explain this association could include biological factors, such as vascular disease leading to depressive symptoms, or lifestyle factors, with depressed patients being less adherent to medical therapy. Whether intensified treatment of depression will reduce stroke risk is an open question.
Note to readers: At the time we reviewed this paper, its publisher noted that it was not in final form and that subsequent changes might be made.

Seemant Chaturvedi, MD, Stewart J. Greenebaum Endowed Professor of Stroke Neurology and Stroke Program Director, University of Maryland Medical System, Baltimore; Vice-Chair for Strategic Operations, Department of Neurology, University of Maryland, Baltimore, USA.

Murphy RP, et al. Depressive symptoms and risk of acute stroke: INTERSTROKE case-control study. Neurology 2023 Mar 8; e-pub (https://n.neurology.org/content/100/17/e1787.long).

This summary is taken from the following Journal Watch titles: Neurology, Psychiatry.