The Biology of Psychosis in Older People

Abstract

The nosology, classification, and biological basis of psychosis in the elderly have been much debated. Psychotic features are seen in schizophrenia, affective illness, and dementia in the elderly. This article reviews evidence for the biological basis of psychosis in older people. In schizophrenia, there is evidence of gender differences in brain volume loss and dopamine receptor numbers, possibly linked to estrogen loss in women. Neuroimaging evidence of ventricular brain changes and more dopamine receptors have also been documented. In Alzheimer's disease, genetic factors such as PS1 and ApoE4 have been associated with psychotic symptoms, and histopathological studies have revealed differences in neuronal pathology. Radiological studies have shown right and left hemisphere differences in size, blood flow, and glucose metabolism between psychotic and nonpsychotic patients. In affective illnesses, there is evidence of structural brain changes in psychotic depression. Ample evidence suggests that biological substrates underlie many psychotic symptoms. More research will identify causal links between brain changes, symptom appearance, and the effects of psychosocial factors in their genesis.

Volumetric neuroimaging investigations in mood disorders: bipolar disorder versus major depressive disorder

“…This article provides an updated summary of quantitative magnetic resonance imaging (MRI) volumetric results in mood disorders, with a particular emphasis on differentiating BD from MDD. Our review complements the extant literature (33–43) with investigations in pediatric and adolescent mood disorders, studies employing voxel‐based morphometry and evaluating white matter changes, and provide a direct comparison between bipolar disorder and major depressive disorder.…”

Terminology and assessment tools of psychosis: A systematic narrative review

“…Instead of an explicit definition, authors often defined the term using examples. Psychotic symptoms are most frequently hallucinations and delusions or more specifically, auditory hallucinations and delusions . Others only directly referred to delusions or hallucinations .…”

“…Others only directly referred to delusions or hallucinations . Thought disorder, paranoia, illusions, ideas of reference, misidentification, disorganization, bizarre or disorganized behavior, psychomotor disorder, behavioral changes, and depersonalization and derealization were also included.…”

“…[195][196][197][198] Others only directly referred to delusions 199,200 or hallucinations. 201 Thought disorder, 97,131,145,156,161,165,167,169,184,189,[192][193][194]196,197,202 paranoia, 100,109,144,167,203 illusions, 100,144,168 ideas of reference, 118 misidentification, 122,134,157 disorganization, 123 bizarre or disorganized behavior, 156,161,165,184,185,189,191,193 psychomotor disorder, 165,184,193 behavioral changes, 159 and depersonalization and derealization 160 were also included.…”

Treatment of psychosis in elderly people

“…• The Capgras type The false belief that previously known people (e.g. wife or caregiver) have been replaced by impostors • The phantom boarder symptom A false belief that guests are living in the person's house • The mirror sign The individual misidentifies his or her own mirror image as someone else • The TV sign Misidentification of television images as real (a variant of this is the magazine sign, in which magazine images on a table are perceived as being real and existing in three-dimentional space (Karim & Burns, 2003)) However, most of these were designed to look at the usefulness of these drugs in controlling the behavioural and psychological symptoms of dementia, not its psychotic symptoms. Schneider (1996), in a meta-analysis of seven placebo-controlled trials of the use of typical antipsychotics, reported significant but modest efficacy.…”