No abstract

SYNOPSISWe examined the prevalence, phenomenology, and clinical correlates of delusions in a consecutive series of 103 patients with probable Alzheimer's disease (AD). Patients were examined with the Present State Exam and the Dementia–Psychosis Scale. Twenty-one patients (20%) met DSM-III-R criteria for a delusional disorder. The most frequent delusion type was paranoid (71%), followed by hypochondriacal (67%), the Capgras syndrome (29%), house misidentification (29%), and grandiose delusions (29%). Out of the 21 AD patients with delusions, 76% had three or more different types of delusions simultaneously. The frequency of delusions was not significantly associated with age, education, or age at dementia onset, and the type and severity of cognitive impairments was similar for AD patients with and without delusions. However, AD patients with delusions had significantly higher mania and anosognosia scores.

This study examined the prevalence and correlates of pathological affect in Alzheimer's disease. A consecutive series of 103 patients with Alzheimer's disease were examined with a comprehensive psychiatric assessment that included the pathological laughing and crying scale (PLACS). Forty patients (39%) showed pathological affect: 25% showed crying episodes, and 14% showed laughing or mixed (laughing and crying) episodes. Patients with pathological affect crying showed significantly higher depression scores and a significantly higher frequency of major depression and dysthymia than patients with no pathological affect. Patients with mixed pathological affect showed significantly more subcortical atrophy on CT than patients with pathological affect crying. Forty seven per cent of the patients with pathological affect had no congruent mood disorder, and they showed a significantly longer duration of illness and more severe anosognosia than patients with pathological affect that was congruent with an underlying mood disorder. The study validates the PLACS, and shows the high prevalence of pathological affect in Alzheimer's disease. (i Neurol Neurosurg Psychiatry 1995;59:55-60)

Objectives-To examine the clinical correlates of catatonia in depression, to validate a scale for catatonia, and to assess the validity of the DSM-IV criteria of the catatonic features specifier for mood disorders.

Although delusions are a frequent finding in patients with Alzheimer's disease (AD), their mechanism is not well known. We carried out Tc 99m HMPAO single-photon emission computed tomography studies in 16 AD patients with delusions and 29 AD patients without delusions comparable in age, years of education, duration of illness, and severity of dementia. Although we found no significant between-group differences in performance on neuropsychological tasks, AD patients with delusions had significantly lower mean cerebral blood flow in both the left and right temporal lobes.