Dexamethasone suppression test and response to antidepressants in depressed mentally handicapped subjects

Nineteen mentally handicapped subjects who were referred to the service with clinically significant depression were assessed with a view to determining the value of the dexamethasone suppression test (DST) in clinical diagnosis and in predicting response to antidepressant treatment. They were assessed initially and then 3 months after they had been treated with a tricyclic antidepressant. It was found that a significant proportion had an abnormal DST response which reversed after recovery in some but not in others. Non-reversal was more likely to occur in the more severely handicapped patients. It was concluded that DST was of little value as a diagnostic tool for the detection of depression in mentally handicapped subjects.