Symptom Profiles in Psychotic Disorder Not Otherwise Specified

Area of Science:

• Psychiatry and Mental Health
• Clinical Psychology
• Neuroscience

Background:

• Psychotic disorder not otherwise specified (PNOS) is diagnosed in approximately 10% of patients with psychotic disorders.
• Limited understanding exists regarding the clinical characteristics of patients diagnosed with PNOS within mental health services.
• This study aims to elucidate the symptom profiles of PNOS patients in comparison to Bipolar Disorder (BD) and Schizophrenia Spectrum Disorder (SZ).

Purpose of the Study:

• To compare the clinical presentations and symptom profiles of patients diagnosed with PNOS against those with BD and SZ.
• To investigate the characteristics of the PNOS diagnostic group, including reasons for diagnosis and demographic factors.
• To assess functional outcomes, symptom severity, and substance use patterns in PNOS patients relative to BD and SZ.

Main Methods:

• Inclusion of 1,221 participants from the Thematically Organized Psychosis study: 792 with SZ, 283 with BD, and 146 with PNOS.
• Diagnosis confirmation using the Structured Clinical Interview for DSM-IV (SCID-I).
• Assessment of functioning (GAF), clinical symptoms (PANSS), and substance use (AUDIT, DUDIT).

Main Results:

• A significant proportion of the PNOS group (44%) did not meet criteria for a specific psychotic disorder, with others having insufficient or contradictory information.
• Substance-induced psychotic disorder was the most frequent reason (28%) for a PNOS diagnosis.
• PNOS patients were younger, more frequently first-episode cases, and exhibited intermediate GAF and PANSS scores between BD and SZ. Substance misuse was more prevalent in the PNOS group.

Conclusions:

• The PNOS diagnosis is more prevalent in first-episode psychosis patients.
• PNOS represents a heterogeneous collection of psychotic syndromes.
• Patients diagnosed with PNOS show functional and symptomatic severity intermediate between Bipolar Disorder and Schizophrenia Spectrum Disorder.