Dexamethasone suppression test and onset of poststroke depression in patients with ischemic infarction.

BACKGROUND: Studies documenting abnormal results in the 1.0-mg dexamethasone suppression test (DST) and the prevalence of depression in stroke patients are usually accomplished between 1 and 6 months poststroke. One study, however, reported that 27% of patients met DSM-III criteria for major depression and 20% for minor depression 1 to 3 weeks poststroke even though previous research has indicated that the prevalence of poststroke depression was greatest at approximately 6 months. Therefore, we decided to assess DST abnormalities and depression within the first month of stroke.
METHOD: Twelve patients with single, computed tomography (CT)-verified, ischemic infarctions were administered the DST at 1 and 3 weeks poststroke. Each patient also received a complete psychiatric evaluation, including a special clinical interview and the 17-item Hamilton Rating Scale for Depression (HAM-D). 3 to 4 weeks poststroke.
RESULTS: DST results were abnormal in 75% of the patients at 1 week poststroke and 50% of the patients at 3 weeks poststroke. Those patients whose HAM-D scores revealed more depressive symptoms at 3 to 4 weeks were more likely to evidence abnormal DST results (cortisol nonsuppression). None of the patients, however, met either DSM-III or modified criteria for clinical depression at 3 to 4 weeks.
CONCLUSION: Poststroke depression appears to have a delayed clinical onset. Abnormal DST results at 3 weeks poststroke may serve as a potential marker for those patients at risk for developing poststroke depression.