Does psychological distress predict the risk of ischemic stroke and transient ischemic attack? The Caerphilly study

Background and Purpose-Psychological distress is common after stroke, but little is known about its etiologic importance, although the general public often ascribes stroke to the experience of stress. Therefore, we examined whether psychological distress leads to an increased risk of ischemic stroke and transient ischemic attack (TIA). Methods-The association between the 30-item General Health Questionnaire (GHQ), a measure of psychological distress, and the incidence of nonfatal and fatal ischemic stroke and TIA was measured by Cox regression modeling in a prospective observational study of 2201 men aged 45 to 59 years in phase II of the Caerphilly cohort. Hazard ratios comparing those with high (greater than or equal to5) and normal GHQ scores were calculated with adjustment for age and other covariates. Results-Twenty-two percent of men suffered from psychological distress, indicated by a score of greater than or equal to5 on the GHQ. There were 130 incident strokes recorded, of which 17 were fatal and 113 nonfatal. The relative risk of incident ischemic stroke was 1.45 (95% CI, 0.98 to 2.14) for those who showed symptoms of psychological distress compared with those who did not. For fatal stroke the relative risk was 3.36 (95% CI, 1.29 to 8.71) and for nonfatal stroke 1.25 (95% CI, 0.82 to 1.92). The relative risk of TIA for the distressed group was 0.63 (95% CI, 0.26 to 1.53). The results were unchanged after adjustment for body mass index, systolic blood pressure, smoking, heavy drinking, social class, and marital status. However, additionally controlling for previously diagnosed ischemic heart disease, diabetes, respiratory disease, and retirement due to ill health attenuated the relative risks, but not markedly. For fatal strokes the relative risk decreased to 2.56 (95% CI, 0.97 to 6.75) when all confounding variables were included in the model. There was a graded association between degree of psychological distress and risk of fatal ischemic stroke. Conclusions-Psychological distress is a predictor of fatal ischemic stroke but not of nonfatal ischemic stroke or TIA. Further work examining the mechanisms of this association is required.