Persecutory Delusions in Dementia

Background: Persecutory delusions are common in dementia. This study was undertaken to investigate the prevalence, associated factors, and characteristics of persecutory delusions in demented patients.

Method: The sample population included 167 demented patients (DSM-III-R criteria) admitted to a geropsychiatric ward. Patients were assessed for the occurrence of any persecutory delusions since the onset of dementia. The content of persecutory delusions, the patients' response to the delusions, and any concomitant psychiatric symptoms were also explored.

Results: Of the 167 demented patients, 45 (26.9%) showed symptoms of persecutory delusions. Patients with persecutory delusions had a higher prevalence of other delusions, hallucinations, and physically aggressive behaviors. The deluded patients often thought that their caregivers were their persecutors and had a wide range of responses to their delusions. After they were hospitalized, many of these patients attacked medical staff and were uncooperative with treatment.

Conclusion: Persecutory delusions are common in dementia of various types. Deluded patients often have vigorous responses to their delusions including physically aggressive behaviors and suicide attempts. Careful evaluation is needed to assess the potential for violent and suicidal behaviors in these patients. Medical staff should be alert to clinical strategies for handling the treatment of such patients when they become violent or uncooperative.

J Clin Psychiatry 1999;60(8):550-553