The Importance of Lesion Location in Poststroke Depression: A Critical Review

Abstract
Background: Mood disorder may be a specific complication of stroke. An earlier finding of an association between left anterior lesions and poststroke depression stimulated interest in the significance of stroke lesion characteristics. Subsequent research efforts, however, often failed to replicate this finding. Objective: This paper represents a critical appraisal of hemispheric lesion localization studies by computed tomography (CT) scanning in poststroke depression. Method: Systematic selection of original studies involved a Medline search and a review of the bibliographies of retrieved articles for additional references. Two sets of inclusion criteria were independently applied to the studies by 2 observers blind to authorship, affiliation, and journal name. Studies that satisfied minimum inclusion criteria, as determined by consensus, were included in the review. Results: Twenty-six original articles were retrieved by the search. Thirteen studies satisfied all or nearly all of the minimum criteria for inclusion. Six of those studies found no difference between right- and left-hemisphere lesions leading to depression. Two studies found right-sided lesions more likely to be associated with depression, while 4 studies found depression to be associated more often with left-sided lesions. One study matched subjects with and without depression for lesion location and size to identify nonlesion risk factors. All studies suffered from methodological limitations, and no studies were completely comparable with respect to sample, timing and analysis of CT scan, and psychiatric evaluation. Conclusion: Based on a systematic review of the present literature, any definitive statements regarding stroke lesion location and risk for depression are not yet substantiated. The authors suggest methodologies for future localization studies of poststroke depression.