Unrecognized dementia in elderly patients admitted to hospital with psychiatric symptoms

In this study, we hypothesized that elderly patients with first admission to a psychiatric hospital commonly suffer from dementia but did not have such a diagnosis on admission. Over a period of 5 years, we surveyed all medical journals from patients treated for the first time at the Department of Psychogeriatrics. By selecting all inpatients treated at the only regional psychiatric hospital within a defined geographic area, the selected patients became representative of this geographic area. After a diagnostic work-up at the hospital, 72 of 239 patients satisfied clinical criteria of dementia. Of these patients, 7 had Alzheimer's disease and 7 had evidence of vascular dementia. We identified 51 of 72 patients (71%) with an endpoint diagnosis of dementia made at the hospital without any clinical information suggesting dementia at the time of hospitalization. Nonspecific psychosis (35%), depression (15%), and behavioral disturbances (8%) represented the most common diagnoses proposed by the referring doctor. In conclusion, dementia may be a difficult diagnosis in elderly patients with psychiatric symptoms. This study reminds clinicians that dementia should be considered in these patients.