Study traces natural history of first-episode psychosis
medwireNews: Around one in five adults who experience a first psychotic episode will subsequently be diagnosed with schizophrenia, and one in 20 will be diagnosed with bipolar disorder, a 5-year follow-up study has found.
The strongest predictors for future schizophrenia were a family history of mental illness and previous criminality, report Robert Bodén (Uppsala University, Sweden) and colleagues in Schizophrenia Research.
The researchers used hospital registry data to identify 1840 Swedish individuals (1112 men) born between 1973 and 1978 who were admitted to hospital with a first diagnosis of non-schizophrenic and non-affective psychosis. The patients’ mean age was 22.6 years.
Baseline diagnoses were acute and transient psychotic disorder in 47% of patients, psychotic disorder due to substance abuse in 24%, other psychoses in 25%, and persistent delusional disorder in 4%. One-third of the cohort reported a prior psychiatric inpatient stay.
Patients were followed up for 5 years from their first psychotic episode. During this time, 18% were diagnosed with schizophrenia or schizoaffective disorder, 5% were diagnosed with bipolar disorder, 38% were diagnosed with other psychiatric disorders, and 33% received no further psychiatric diagnosis or treatment.
After adjusting for age and gender, the strongest predictors for a subsequent schizophrenia diagnosis were having a first-degree relative who was hospitalized for schizophrenia and/or bipolar disorder, which nearly doubled the risk (odds ratio [OR]=1.9), and severe criminality, which halved the risk (OR=0.5).
Bodén et al conclude that there is a “wide range” of diagnostic outcomes after a first hospitalization for psychosis and that the predictors for subsequent schizophrenia diagnosis may be used clinically to identify patients at greatest risk.
“Early identification of patients who are at higher risk of developing a chronic psychotic disorder might inform a rational allocation of health care resources to patients with most needs,” they add.
medwireNews (www.medwirenews.com) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2013
By Joanna Lyford, Senior medwireNews Reporter