Development of depressed mood predicts onset of psychotic disorder in individuals who report hallucinatory experiences.
OBJECTIVE
Current psychological theories state that the clinical outcome of hallucinatory experiences is dependent on the degree of associated distress, anxiety, and depression. This study examined the hypothesis that the risk for onset of psychotic disorder in individuals with self-reported hallucinatory experiences would be higher in those who subsequently developed depressed mood than in those who did not.


METHODS
A prospective cohort study of a general population sample.


METHODS
A sample of 4,670 individuals with no lifetime evidence of any psychotic disorder were interviewed with the Composite International Diagnostic Interview Schedule (CIDI) at baseline and 1 and 3 years later. At Year 3, individuals with CIDI evidence of psychotic symptoms were interviewed by clinicians to identify potential onset of psychotic disorder. Psychotic disorder was specified at three levels; two involving severity of positive symptoms of psychosis, and one using additional clinical judgment of need for care.


RESULTS
Given the presence of hallucinatory experiences at baseline, the increase in risk of having the psychosis outcome at Year 3 was higher in the group with depressed mood at Year 1 than in the group without depressed mood at Year 1 (any level of psychotic symptoms: risk difference 17.0%, 95% CI - 1.7, 35.7; severe level of psychotic symptoms: risk difference 21.7%, 95% CI 3.2, 40.2; needs-based diagnosis of psychotic disorder: risk difference 16.8%, 95% CI 0.4, 33.3).


CONCLUSIONS
The results are in line with current psychological models of psychosis that emphasize the role of secondary appraisals of psychotic experiences in the onset of clinical disorder.
Krabbendam
Lydia
L
Department of Psychiatry and Neuropsychology, Maastricht University, The Netherlands. l.krabbendam@sp.unimaas.nl
Myin-Germeys
Inez
I
Hanssen
Manon
M
de Graaf
Ron
R
Vollebergh
Wilma
W
Bak
Maarten
M
van Os
Jim
J
D000328:Adult; D010054:Brief Psychiatric Rating Scale; D015331:Cohort Studies; D003863:Depression / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology*; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D005500:Follow-Up Studies; D006212:Hallucinations / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology*; D006801:Humans; D008297:Male; D015995:Prevalence; D011446:Prospective Studies; D011618:Psychotic Disorders / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology*; D012307:Risk Factors; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires