Cognition, hallucination severity and hallucination-specific insight in neurodegenerative disorders and eye disease. Issue 2 (4th May 2022)

• Record Type: Journal Article
• Authors: Montagnese, Marcella; Vignando, Miriam; Collerton, Daniel; ffytche, Dominic; Mosimann, Urs Peter; Taylor, John-Paul; daSilva Morgan, Katrina; Urwyler, Prabitha
• Is Part Of: Cognitive neuropsychiatry. Volume 27:Issue 2/3(2022)
• Page Start: 105
• Page End: 121
• Publication Date: 2022-05-04
• Subjects: Hallucinations -- neurodegeneration‌ -- distress -- psychosis -- eye disease; Neuropsychology -- Periodicals; 616.8
• DOI: 10.1080/13546805.2021.1960812
• Languages: English
• ISSNs: 1354-6805

Abstract

ABSTRACT: Introduction: Hallucinations occur across neurodegenerative disorders, with increasing severity, poorer cognition and impaired hallucination-specific insight associated with worse outcomes and faster disease progression. It remains unclear how changes in cognition, temporal aspects of hallucinations, hallucination-specific insight and distress relate to each other. Methods: Extant samples of patients experiencing visual hallucinations were included in the analyses: Parkinson's Disease ( n = 103), Parkinson's Disease Dementia ( n = 41), Dementia with Lewy Bodies ( n = 27) and Eye Disease ( n = 113). We explored the relationship between factors of interest with Spearman's correlations and random-effect linear models. Results: Spearman's correlation analyses at the whole-group level showed that higher hallucination-specific insight was related to higher MMSE score ( r s = 0.39, p < 0.001) and less severe hallucinations ( r s = −0.28, p < .01). Linear mixed-models controlling for diagnostic group showed that insight was related to higher MMSE ( p < .001), to hallucination severity ( p = 0.003), and to VH duration ( p = 0.04). Interestingly, insight was linked to the distress component but not the frequency component of severity. No significant relationship was found between MMSE and hallucination severity in these analyses. Conclusion: Our findings highlight the importance of hallucination-specific insight, distress and duration across groups. A better understanding of the role these factors play in VH may help with the development of future therapeutic interventions trans-diagnostically.