Healthy individuals with auditory verbal hallucinations; who are they? Psychiatric assessments of a selected sample of 103 subjects

Epidemiological studies suggest that auditory verbal hallu-cinations (AVH) occur in approximately 10%–15 % of the general population, of whom only a small proportion has a clinically relevant psychotic disorder. It is unclear whether these hallucinations occur as an isolated phenom-enon or if AVH in nonclinical individuals are part of a more general susceptibility to schizophrenia. For this study, 103 healthy individuals with frequent AVH were compared with 60 controls matched for sex, age, and education. All participants were examined by a psychiatrist using stan-dardized diagnostic interviews and questionnaires. The individuals with AVH did not have clinically defined delu-sions, disorganization, or negative or catatonic symptoms, nor did they meet criteria for cluster A personality disorder. However, their global level of functioning was lower than in the controls and there was a pronounced increase on all sub-clusters of the Schizotypal Personality Questionnaire (SPQ) and the Peters Delusion Inventory, indicating a gen-eral increased schizotypal and delusional tendency in the hallucinating subjects. History of childhood trauma and family history of axis I disorders were also more prevalent in these individuals. We showed that higher SPQ scores, lower education, and higher family loading for psychiatric disorders, but not presence of AVH, were associated with lower global functioning. Our data suggest that AVH in otherwise healthy individuals are not an isolated phenom-enon but part of a general vulnerability for schizophrenia. Key words: hallucinations/healthy/spectrum/schizotypy/ functionin