Background: Depression affects up to 40% of patients with ischemic stroke. The relationship between site and size of brain infarcts and poststroke depression is still not well characterized. Further possible contribution and interaction of white matter lesions and brain atrophy has not been studied previously. We conducted a magnetic resonance image-based study of the radiologic correlates of depression in a large, well-defined series of patients with ischemic stroke.
Methods: Modified DSM-III-R and DSM-IV criteria were used to diagnose depressive disorders during a comprehensive psychiatric evaluation in 275 of 486 consecutive patients aged 55 to 85 years 3 to 4 months after ischemic stroke. A standardized magnetic resonance imaging protocol detailed side, site, type, and extent of brain infarcts and extent of white matter lesions and brain atrophy.
Results: Depressive disorders were diagnosed in 109 patients (40%). Patients with depression had a higher number and larger volume of infarcts affecting the prefrontosubcortical circuits, especially the caudate, pallidum, and genu of internal capsule, with left-sided predominance. Extent of white matter lesions and atrophy did not differ in patients with and without depression. Independent correlates of poststroke depression in a logistic regression model were mean frequency of infarcts in the genu of internal capsule on the left side (odds ratio [OR], 3.2; 95% confidence interval [CI], 1.0-10.1), mean frequency of infarcts in the pallidum of any side (OR, 1.6; 95% CI, 1.1-2.3), and mean volume of infarcts in the right occipital lobe (OR, 0.98; 95% CI, 0.96-0.99).
Conclusion: Lesions affecting the prefrontosubcortical circuits, especially on the left side, are correlates of depression after ischemic stroke.