Depression, Other Psychosocial Distresses Linked to Stroke

Pauline Anderson

December 13, 2012

Older adults who are depressed, stressed, or dissatisfied with their life are at increased risk of suffering a stroke and of dying from a stroke, a new study has found.

The study showed that those who faced the highest level of psychosocial distress had a significantly increased risk of having a stroke and up to 3 times the risk of stroke mortality compared with those with the least amount of distress.

"Our findings clearly document important adverse effects of psychosocial distress on cerebrovascular disease risk in the elderly," write the authors, including senior author Susan Everson-Rose, PhD, associate professor of medicine and associate director of the Program in Health Disparities Research, University of Minnesota, Minneapolis.

The study is published online December 13 in Stroke.

Distress Score

The study used data from the Chicago Health and Aging Project (CHAP), an ongoing, longitudinal study investigating chronic illnesses in elderly residents of 3 adjacent neighborhoods in Chicago, who represent a broad range of socioeconomic backgrounds. Researchers conducted baseline interviews to gather information on medical history, cognitive health, socioeconomic status, behavioral patterns, and psychosocial characteristics, repeating the interviews in 3-year cycles.

The second cycle of interviews (1997 to 1999) assessed the broadest range of psychosocial characteristics and served as the baseline for the current analysis, which included 4120 mostly black and female participants whose average age was 77 years. Most had a high school education and an average of 1 chronic condition; 13.1% reported a history of stroke.

For information on stroke hospitalizations, researchers accessed the Centers for Medicare and Medicaid Services Medicare Claims data (because some participants were involved in a health maintenance organization, only 2649 participants were analyzed for rates of incident stroke). To verify deaths, the authors used linkages with the National Death Index.

To assess psychosocial distress, investigators created a distress score that factored in 4 psychosocial measures: depressive symptoms, perceived stress, neuroticism (a personality domain characterized by anxious, angry, and vulnerable traits), and life satisfaction. The higher the score is, the higher the distress.

The study showed a dose-response pattern of risk for incident stroke. Relative to the least distressed quartile, the hazard ratios (HRs) for the second, third, and fourth quartiles were 1.27 (95% confidence interval [CI], 0.98 - 1.65; P = .067), 1.44 (95% CI, 1.10 - 1.87; P = .0068), and 1.54 (95% CI, 1.16 - 2.04; P = .0025), respectively, in a model adjusted for age, race, and sex. Associations were reduced after adjustment for stroke risk factors.

With distress modeled categorically and adjusting for age, race, and sex, participants in the highest quartile had nearly a 3 times (HR, 2.97; 95% CI, 1.81 - 4.88; P < .0001) greater risk of dying from stroke relative to those with the lowest distress scores. Those in the third quartile had nearly 2 times the risk (HR, 1.98; 95% CI, 1.19 - 3.30; P = .0091).

Analyses of stroke subtypes revealed that distress was significantly related to incident hemorrhagic strokes, but not to ischemic strokes after adjustment for covariates.

Behavioral Factors

Psychological and behavioral factors may play a role in raising stroke risk. Very distressed people may be less likely or less able to comply with treatment recommendations or to maintain a healthy lifestyle.

"Our most distressed participants were less physically active, and had a higher prevalence of cardiovascular disease and diabetes mellitus, suggesting potentially greater disease burden in this group, which could make lifestyle management more challenging," the authors write. However, in this study, controlling for these factors had little effect on the relationship between distress and either stroke mortality or hemorrhagic strokes.

The pathways by which distress increases stroke risk are not fully understood, said the authors. Possible mechanisms may involve hypothalamic-pituitary-adrenal dysregulation related to stress that may increase circulating catecholamines, endothelial dysfunction, and platelet activation, culminating in a hypercoaguable state.

Neuroendocrine and inflammatory effects of chronic stress and negative emotional states may also contribute to the increased risk. However, the authors pointed out that these pathways are probably more important for ischemic than hemorrhagic stroke and that the current study found much stronger findings for hemorrhagic stroke.

The study lacked data on inflammatory and neuroendocrine biomarkers that might have shed more light on pathways that may link psychosocial distress to stroke risk. Another limitation was that CHAP doesn't include imaging data that might provide important information about the types of strokes experienced by study participants. Also, the study assessed psychosocial distress at just one point in time, so it couldn't determine whether distress levels changed or whether such changes influenced stroke risk.

Dr. Everson-Rose is supported in part by a grant from the National Institute on Minority Health and Health Disparities (NIMHD).

Stroke. Published online December 13, 2012.