Study questions current hypotheses surrounding duration of untreated psychosis

Researchers have found evidence countering the hypothesis that a long duration of untreated psychosis is associated with “insidious, severe psychotic disorder,” as well as against the toxicity of untreated psychosis, according to study findings published in American Journal of Psychiatry.

“[Duration of untreated psychosis] is one of the more potent predictors of course in schizophrenia, with an effect larger than that of premorbid adjustment and age at onset,” Katherine G. Jonas, PhD, of the department of psychiatry and behavioral health at Stony Brook University in New York, and colleagues wrote. “Gender may play a larger role, but unlike most other predictors, [duration of untreated psychosis] is modifiable. One aim of early intervention programs has been to identify psychosis in its early stages and minimize [duration of untreated psychosis].”

The researchers noted that although a long duration of untreated psychosis predicts worse treatment outcomes and illness severity, it remains unclear why this association exists. Beyond the toxicity hypothesis or the possibility that longer duration reflects a more severe schizophrenia form, the association may be an artifact of lead-time bias.

To test these hypotheses, the researchers analyzed data from the Suffolk County Mental Health Project — a longitudinal study of first-admission psychosis. They included data of 287 individuals with schizophrenia or schizoaffective disorder, with 2,137 observations from childhood to 20 years after first admission. They defined duration of untreated psychosis as days from first psychotic symptom to first psychiatric hospitalization and assessed psychosocial function using the Premorbid Adjustment Scale and the Global Assessment of Functioning Scale. The researchers used multilevel spline regression models adjusted for antipsychotic medication, occupational status, gender and race to estimate psychosocial function trajectories.

Results showed patients with both long- and short-duration of untreated psychosis experienced similar psychosocial function declines, which occurred at different times relative to first admission. Patients with long duration experienced most of these declines before first admission, whereas patients with short duration experienced declines after first admission, the researchers noted. Upon analysis of psychosocial function relative to psychosis onset, they found that duration of untreated psychosis did not predict illness course.

“To avoid confounding by lead-time bias, studies of first-episode schizophrenia should estimate the course of illness and treatment response relative to time since psychosis onset,” Jonas and colleagues wrote. “Treatments more potent than those available to this cohort may be able to alter illness trajectory and make early intervention beneficial.” – by Joe Gramigna

Disclosures: Jonas reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.