Hallucinations Can Be Marker For Variety of Psychiatric Disorders in Youth

Auditory or other hallucinations are not uncommon in childhood and adolescence, are most often transitory, and do not necessarily indicate that later onset of psychosis is inevitable.

However, hallucinations experienced at multiple points in adolescence are an indicator of persistence of symptoms and appear to be associated with a significantly higher risk of a variety of mental illnesses later in life—not only psychosis—as well as with suicidality.

Those were among the take-away messages from several speakers at the International Congress of Schizophrenia Research in San Diego in March.

A World Health Organization (WHO) survey of more than 31,000 adults found that the lifetime prevalence of any hallucination was 5.2 percent. Of those reporting hallucination, 32 percent said they experienced hallucination just once, and another 32 percent said they experienced hallucinations between two and five times.

Persistence of such experiences is a risk factor for later onset of disorders. James Scott, M.D., Ph.D., an affiliate associate professor at the University of Queensland Centre for Clinical Research, Australia, reported results from the Mater-University of Queensland Study of Pregnancy (MUSP). This study analyzed data on the mental health outcomes of individuals aged 30 to 33 who had filled out the Youth Self-Report Questionnaire at ages 14 and 21 and individuals who reported never having experienced hallucinations.

A total of 455 participants (12.9 percent of the sample) self-reported having hallucinations at age 14 but not at age 21, and 140 (4 percent) self-reported hallucinations at both 14 and 21. These individuals were compared with 490 controls who reported no history of hallucinations at either time point.

Lifetime diagnoses of mental disorders were ascertained by the Structured Clinical Interview for DSM Disorders (DSM IV-TR), and suicidal behavior was measured by self-report. Scott and colleagues also identified participants not engaged in education or employment (NEET) using the Activity and Participation Questionnaire (APQ6). Quality of life was measured using the Assessment of Quality of Life (AQoL) scale.

Those with hallucinations at both 14 and 21 years had close to nine times the chance of having a psychotic disorder by 30 years of age, 2.3 times the chance of having a substance use disorder, and 3.6 times the chance of having an eating disorder. Moreover, those who reported hallucinations at both time points had more than seven times the risk of any lifetime suicide attempt. They were also more likely to be unemployed or not engaged in training and four times as likely to have poor quality of life, Scott reported.

Scott said adolescent experience of hallucinations calls for a thorough mental health assessment, including for present or past trauma, suicidal ideation, and substance use. But equally important is the message that most adolescent experience of hallucination is transitory.

“When there is no evidence of current psychosis, advice and reassurance are called for along with follow-up to determine whether hallucinations continue,” he said. “Most adolescents who experience hallucination are not going to progress to psychosis, and most don’t develop schizophrenia. But it’s really important to avoid cannabis use.”

Scott was joined at the symposium by Ian Kelleher, M.D., Ph.D., who discussed the relationship between hallucinations and suicide—especially whether the relationship is mediated by the strong relationship between borderline personality disorder (BPD) and suicide. Kelleher is a research lecturer at the Royal College of Surgeons in Ireland.

Kelleher reported data that was published in the March 2017 editions of the British Journal of Psychiatry and Acta Psychiatrica Scandinavica on a nationally representative sample of individuals from the 2007 Adult Psychiatric Morbidity Study of British households. Participants were assessed for common mental disorders, BPD (clinical and subclinical), suicidal behavior, and auditory and visual hallucinations.

He and colleagues found that approximately 4 percent of the total sample (n=323) reported hallucinations. These experiences were associated with increased odds of suicide attempts across the board—whether it be in individuals with BPD, individuals with a common mental disorder, individuals without a common mental disorder, or individuals with neither a common mental disorder nor BPD.

Kelleher said the results suggest that the relationship between hallucinations and suicide is not driven by association with BPD and that experience of hallucinations is associated not only with psychosis, but also with several common mental disorders. “Hallucinations should be regarded as trans-diagnostic markers for a variety of mental illnesses,” he said.

He said that the high prevalence of hallucination among children and adolescents and the association with multiple disorders and suicide call for greater clinical attention to the subject.

“A huge number of people have these experiences, and hallucinations in adolescence are most commonly transient,” he said. “Very few people talk about them, and parents are often unaware of their children’s experience of hallucinations. When people look online for information, the only thing they are pointed to is psychosis and schizophrenia, and people are frightened by that. But it’s important to realize that hallucinations can occur across a wide range of mental illnesses, not just psychosis.” ■

More information about discussions at ICOSR can be accessed here. “Psychotic Experiences and Suicide Attempt Risk in Common Mental Disorders and Borderline Personality Disorder” is available here.