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Evidence for an interrelated cluster of Hallucinatory experiences in the general population: an incidence study

Published online by Cambridge University Press:  22 April 2020

Tais S. Moriyama ,
Marjan Drukker ,
Sinan Guloksuz ,
Magreet ten Have ,
Ron de Graaf ,
Saskia van Dorsselaer ,
Nicole Gunther ,
Maarten Bak  and
Jim van Os
Tais S. Moriyama
Affiliation:
Instituto Bairral, Itapira, Brazil Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University Medical Centre, Maastricht, The Netherlands
Marjan Drukker
Affiliation:
Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University Medical Centre, Maastricht, The Netherlands
Sinan Guloksuz
Affiliation:
Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University Medical Centre, Maastricht, The Netherlands Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
Magreet ten Have
Affiliation:
Department of Epidemiology, Netherlands Institute of Mental Health and Addiction, Utrecht, The Netherlands
Ron de Graaf
Affiliation:
Department of Epidemiology, Netherlands Institute of Mental Health and Addiction, Utrecht, The Netherlands
Saskia van Dorsselaer
Affiliation:
Department of Epidemiology, Netherlands Institute of Mental Health and Addiction, Utrecht, The Netherlands
Nicole Gunther
Affiliation:
Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University Medical Centre, Maastricht, The Netherlands School of Psychology, Open University, Heerlen, The Netherlands
Maarten Bak
Affiliation:
Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University Medical Centre, Maastricht, The Netherlands
Jim van Os*
Affiliation:
Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University Medical Centre, Maastricht, The Netherlands Department of Psychiatry, Brain Centre Rudolf Magnus, University Medical Centre Utrecht, Utrecht, The Netherlands Department of Psychosis Studies, King's College London, King's Health Partners, Institute of Psychiatry, London, UK
*
Author for correspondence: Jim van Os, E-mail: j.j.vanos-2@umcutrecht.nl
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Abstract

Background

Although hallucinations have been studied in terms of prevalence and its associations with psychopathology and functional impairment, very little is known about sensory modalities other than auditory (i.e. haptic, visual and olfactory), as well the incidence of hallucinations, factors predicting incidence and subsequent course.

Methods

We examined the incidence, course and risk factors of hallucinatory experiences across different modalities in two unique prospective general population cohorts in the same country using similar methodology and with three interview waves, one over the period 1996–1999 (NEMESIS) and one over the period 2007–2015 (NEMESIS-2).

Results

In NEMESIS-2, the yearly incidence of self-reported visual hallucinations was highest (0.33%), followed by haptic hallucinations (0.31%), auditory hallucinations (0.26%) and olfactory hallucinations (0.23%). Rates in NEMESIS-1 were similar (respectively: 0.35%, 0.26%, 0.23%, 0.22%). The incidence of clinician-confirmed hallucinations was approximately 60% of the self-reported rate. The persistence rate of incident hallucinations was around 20–30%, increasing to 40–50% for prevalent hallucinations. Incident hallucinations in one modality were very strongly associated with occurrence in another modality (median OR = 59) and all modalities were strongly associated with delusional ideation (median OR = 21). Modalities were approximately equally strongly associated with the presence of any mental disorder (median OR = 4), functioning, indicators of help-seeking and established environmental risk factors for psychotic disorder.

Conclusions

Hallucinations across different modalities are a clinically relevant feature of non-psychotic disorders and need to be studied in relation to each other and in relation to delusional ideation, as all appear to have a common underlying mechanism.

Keywords

At-risk mental statecohorthallucinationsincidencemental disordersmental healthpsychosispsychotic experiences
Type
Original Article
Information
Psychological Medicine , Volume 51 , Issue 12 , September 2021 , pp. 2034 - 2043
Copyright
Copyright © The Author(s), 2020. Published by Cambridge University Press

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