Depressive Symptoms Linked to Higher Risk of Acute Stroke

Symptoms of depression were associated with an increased risk of acute stroke, according to an international case-control study.

Among more than 26,000 participants in the INTERSTROKE study, self-reported depressive symptoms were associated with significantly greater odds of acute stroke (OR 1.46, 95% CI 1.34-1.58), including ischemic stroke (OR 1.44, 95% CI 1.32-1.58) and intracerebral hemorrhage (OR 1.56, 95% CI 1.28-1.91), reported Robert P. Murphy, MB, of the HRB Clinical Research Facility Galway and the School of Medicine at the University of Galway, and co-authors.

While depressive symptoms were not associated with a greater odds of worse baseline stroke severity (OR 1.02, 95% CI 0.94-1.10), they were linked to greater odds of poor functional outcomes 1 month after acute stroke (OR 1.09, 95% CI 1.01-1.19), they noted in Neurology.

Patients with depressive symptoms were also more likely to die during the first month after stroke (10% vs 8.1%, P=0.003).

“Our results show that symptoms of depression can have an impact on mental health, but also increase the risk of stroke,” Murphy told MedPage Today. “Physicians should be looking for these symptoms of depression and can use this information to help guide health initiatives focused on stroke prevention.”

“Depression is an important risk factor for acute stroke and is potentially a modifiable contributor to the global burden of stroke,” he added. “This study adds to prior evidence, which was predominantly in high-income countries.”

INTERSTROKE is a global study that was conducted in 32 countries with a range of economic status, including middle- and low-income countries. This broad approach “adds to the collective body of research that strongly suggests an increased risk of stroke associated with depressive symptoms,” Murphy said.

In addition, the use of self-reporting to classify depressive symptoms allowed the researchers to compare people across different countries and regions of the world.

Murphy noted that future studies should look to explore the relationship between depressive symptoms prior to stroke and worse functional outcomes after stroke, which could help determine targeted interventions for patients with depressive symptoms presenting with stroke.

For this study, the researchers included 13,392 patients in 32 countries who were hospitalized with incident acute stroke confirmed by CT or MRI from January 2007 to August 2015. A control group of 13,485 participants were matched based on sex, age, and location.

Of the total 26,877 participants, mean age was 61.7, and 40.4% were women.

Murphy and team asked standardized questions about self-reported depressive symptoms during the previous 12 months and recorded use of prescribed antidepressant medications.

The prevalence of depressive symptoms within the previous 12 months was higher in stroke patients compared with control participants (18.3% vs 14.1%, P<0.001) and differed by region (P for interaction<0.001), with the lowest prevalence in China (6.9% in controls) and the highest in South America (32.2% of controls).

An analysis stratified by number of endorsed questions in the depression questionnaire showed a greater magnitude of association, from mild depressive symptoms (less than three questions endorsed; OR 1.35, 95% CI 1.19-1.53) to moderate depressive symptoms (3-4 questions endorsed; OR 1.58, 95% CI 1.41-1.75) and severe depressive symptoms (five or more endorsed; OR 1.54, 95% CI 1.38-1.72).

The authors acknowledged several limitations to their study, including that depressive symptoms were assessed only at a single baseline examination. In addition, they asked about depressive symptoms occurring over only the last year, which may have underestimated depression ascertainment.