Long-term follow-up of depressive pseudodementia of the aged.

Forty-four elderly patients of both sexes (mean age 76.5 years) suffering from depressive pseudodementia were intensively treated for the depression. When that cleared up, cognitive function reverted to premorbid level. Patients were regularly interviewed and retested at six months intervals for four to 18 years (average 8). Some patients experienced, during the follow-up period, a recurrence of the depression for which they were again successfully treated. At the end of the observation period, 39 of the 44 patients (89%) had developed a dementia syndrome of the Alzheimer type.