Psychotic Symptoms in a Population-Based Sample of 85-Year-Old Individuals With Dementia

Abstract

Psychotic symptoms are common in elderly persons with dementia. These symptoms affect a person's ability to function in daily life and put strain on the caregiver. Most studies focus on psychotic symptoms in clinical samples with Alzheimer disease (AD). Thus, their prevalence and relation with dementia subtype and severity in very old populations is unclear. We assessed a representative sample of 85-year-old individuals living in Gothenburg, Sweden (n = 494) using neuropsychiatric examinations, key informant interviews, and medical record reviews; 147 had dementia. Dementia and its severity were diagnosed in accordance with Diagnostic and Statistical Manual of Mental Disorders (Third Edition, Revision [DSM-III-R]) criteria. Alzheimer disease according to the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) criteria was diagnosed in 64 persons and vascular dementia (VaD) according to Erkinjuntti criteria was observed in 69. Fourteen had dementia due to other causes. Psychotic symptoms were classified according to DSM-III-R. The prevalence of psychotic symptoms in this very old population was 36% among AD cases compared to 54% in VaD cases (P = .04). Proportions with psychotic symptoms increased with increasing dementia severity in individuals with AD. No such association could be shown in those with VaD. This finding of a high proportion of psychotic symptoms also in individuals with mild severity of VaD should alert health professionals to evaluate dementia in very old patients who present with hallucinations or delusions.

Neurobiology of Delusions in Alzheimer’s Disease

“…Unfortunately, despite a useful longitudinal approach, psychosis was not described in terms of its components, limiting the utility of this study in contributing to the understanding of the neurobiology of delusions. Very recently, in a cross-sectional sample of much older adults with AD (>85 years of age), Ostling and colleagues [15] reported that 22% had delusions and 30% had hallucinations. Although psychosis in general and hallucinations increased with dementia severity, no statistically significant association was found between delusions and dementia severity.…”

Preclinical Polymodal Hallucinations for 13 Years before Dementia with Lewy Bodies

“…On the contrary, BG's dementia was characterized by severe and multiple cognitive impairments, suggesting diffuse cortical damage (i.e., retrograde and autobiographical amnesia, aphasia, constructional and dressing apraxia, a complex misidentification syndrome, etc.). Second, hallucinations in the early stages of subcortical vascular dementia do not usually involve symptoms that occur during sleep induction or awakening, such as the preferential hypnagogic and hypnopompic hallucinations experienced by BG [65]. Third, the clinical picture of subcortical vascular dementia involves widespread manifestations, including cognitive impairments, personality and mood disorders (i.e., apathy, irritability, and vascular depression), psychotic symptoms, gait disturbances, motor dysfunction, and urinary symptoms [67, 69].…”

Psychosis in Later Life

“…32 It is also worth noting that psychotic symptoms appear to be more common among inpatient populations than outpatient populations, 10 and that dementia severity appears to be positively associated with the presence and severity of psychosis. 33,34 Psychosis in Alzheimer's disease typically has a unique clinical appearance in comparison to psychosis in other late-life, non-dementia illnesses. For instance, unlike in schizophrenia, the hallucinations seen in Alzheimer's disease tend to be visual, not auditory, in nature, 10 and the delusions tend not to be bizarre or complex, but are simple/non-complex.…”

“…34 In vascular dementia, as in Parkinson's dementia, but not Alzheimer's or Lewy body dementia, the severity of dementia does not appear to be associated with the presence or severity of psychosis. 33,34 Secondary Psychoses In addition to the aforementioned neuropsychiatric disorders, a variety of medical and neurological problems in older individuals can result in psychosis. It is important to identify such cases since the management of symptoms depends on the underlying cause and will tend to focus on addressing the primary problem.…”