Risk factors for psychosis in an ultra high-risk group: psychopathology and clinical features.
The identification of individuals at high risk of developing a psychotic disorder has long been a goal of clinicians because it is thought that early treatment of this group may prevent onset of the disorder. However, little is known of predictive factors of psychosis, even within a high-risk group. This study followed up 104 young people thought to be at 'ultra high risk' for schizophrenia and other psychotic disorders by virtue of having a family history of psychotic disorder combined with some functional decline or the presence of subthreshold or self-limiting psychotic symptoms. All subjects were therefore symptomatic, but not psychotic, at intake. Thirty-six subjects (34.6%) developed frank psychotic symptoms within 12 months. Measures of symptom duration, functioning, disability and psychopathology were made at intake, 6 and 12 months. Poor functioning, long duration of symptoms, high levels of depression and reduced attention were all predictors of psychosis. A combination of family history of psychosis, a recent significant decrease in functioning and recent experience of subthreshold psychotic symptoms was also predictive of psychosis. Combining highly predictive variables yielded a method of psychosis prediction at 12 months with good positive predictive value (80.8%), negative predictive value (81.8%) and specificity (92.6%) and moderate sensitivity (60.0%). Within our symptomatic high-risk group, therefore, it appears possible to identify those individuals who are at particularly high risk of developing a psychotic disorder such as schizophrenia. Given the very high PPV and low false positive rate with this two-step process, it may be justifiable to target these individuals for intensive monitoring of mental state and even low-dose neuroleptic medication or other biological and psychosocial treatments depending on clinical condition. This indicated prevention approach could be further developed and preventive strategies in the psychoses refined.
Yung
Alison R
AR
Department of Psychiatry, University of Melbourne and ORYGEN Research Centre, Australia. aryung@unimelb.edu.au
Phillips
Lisa J
LJ
Yuen
Hok Pan
HP
McGorry
Patrick D
PD
D000293:Adolescent; D000328:Adult; D000341:Affective Disorders, Psychotic / Q000453:epidemiology; D001526:Behavioral Symptoms / Q000503:physiopathology; D016009:Chi-Square Distribution; D003863:Depression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009341:Negativism; D009483:Neuropsychological Tests; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011569:Psychiatric Status Rating Scales; D011599:Psychopathology; D011618:Psychotic Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D011788:Quality of Life; D012043:Regression, Psychology; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D012559:Schizophrenia / Q000453:epidemiology; D012565:Schizophrenic Psychology; D013997:Time Factors