Depression and its relation to lesion locationafter stroke

The study of discrete organic cerebral lesions resulting inclearly definable psychiatric disorders may provide an understanding ofthe underlying patho-physiological basis of these disorders. However,the relation between lesion location and psychiatric illness afterstroke remains unclear. Fifty five patients referred to hospital wereidentified who had a single lesion on CT which was consistent withtheir neurological presentation and who did not have evidence of apersistent affective disorder at the time of the stroke. Six monthsafter stroke standardised psychiatric assessment disclosed that 26% ofthe patients met DSM-IV criteria for an anxiety or depressive disorder,with depression the most common diagnosis (20%). Pathologicalemotionalism was diagnosed in 18% of patients, particularly those whowere depressed (p<0.0001). Depression was significantly associatedwith larger lesions involving the right cerebral hemisphere (p=0.01).The importance of depression as a consequence of stroke has beenclarified by the studies in this area. However, wide confidenceintervals support the possibility that significant results may be dueto chance. A systematic review of these studies is now needed if aconsensus is to be reached.