Post-stroke depression and depression-executive dysfunction syndrome are associated with recurrence of ischaemic stroke

Background: Depression and depression-executive dysfunction syndrome (DES) are common neuropsychiatric consequences of stroke. We hypothesized that if stroke as a cerebrovascular event causes depression, this so-called post-stroke depression will further increase the risk of recurrent stroke. The objective of the study was to investigate whether patients with post-stroke depression or DES have increased rates of stroke recurrence. Methods: We included 223 patients from the Helsinki Stroke Aging Memory cohort (n = 486) admitted to Helsinki University Central Hospital with a follow-up of 12 years. We included only patients with first-ever ischaemic stroke who were testable for depression and executive dysfunction. For follow-up, national register data were reviewed for all diagnosis codes of ischaemic stroke, survival data and causes of death. Neuropsychological and neuropsychiatric evaluations for depression and executive functions were performed 12-20 weeks after the index stroke. Univariate analysis was performed using χ², Mantel-Haenszel, ANOVA, and Kaplan-Meier log rank analyses. A Cox multivariable model with forced entry was used to adjust for stroke risk factors (age, gender, smoking, atrial fibrillation, hypertension, diabetes, peripheral arterial disease, hypercholesterolaemia). Results: The mean time to first recurrent stroke was shorter for the depressed patient group (8.15, 95% CI 7.11-9.19 vs. 9.63, 8.89-10.38 years) and even shorter for patients with DES (7.15, 5.55-8.75 vs. 9.75, 9.09-10.41 years) compared to the remaining groups, respectively. The cumulative risk for recurrent ischaemic stroke in the 12-year follow-up was higher for the depression group (log rank p = 0.04) and for the DES group (log rank p = 0.01) compared to the remaining groups, respectively. Cox multivariable analyses revealed that the older age of the patient (1.05: 1.01-1.08/year), the absence of hypercholesterolaemia (0.24: 0.09-0.59), depression (1.68: 1.07-2.63), and DES (1.95: 1.14-3.33) were all associated with recurrent stroke. Conclusions: Depression and especially DES are associated with a shorter interval to recurrence of ischaemic stroke but executive dysfunction alone is not associated with a more rapid stroke recurrence. Diagnosis and treatment of depressive syndromes should be considered as a part of secondary prevention in patients with ischaemic stroke.