Anomalous self-experience in substance-induced and primary psychotic disorders: a cross-sectional comparative study...

Area of Science:

• Psychiatry
• Phenomenology
• Clinical Psychology

Background:

• Anomalous self-experiences (ASEs) are considered a core feature of primary psychotic disorders (PPDs).
• It is unclear if similar self-disorders occur in substance-induced psychosis (SIP), which can mimic PPDs early on.

Purpose of the Study:

• To compare ASEs between PPD and SIP using the Examination of Anomalous Self-Experience (EASE) interview.
• To assess the diagnostic specificity of ASEs and determine their presence in SIP versus PPDs.

Main Methods:

• 54 clinically stable patients (27 with schizophrenia spectrum disorders, 27 with SIP) were assessed using the EASE interview.
• DSM-5 criteria were used for diagnosis. Non-parametric statistics and logistic regression analyzed domain-specific differences.

Main Results:

• Total EASE scores did not differ between groups.
• Domain 4 (Demarcation/Transitivism) was significantly higher in the SIP group, indicating more self-world boundary disturbances.
• Domains 2 (Self-awareness/Presence) and 5 (Existential Reorientation) trended higher in the PPD group.

Conclusions:

• ASEs, particularly self-world boundary disturbances, are not exclusive to PPDs and can manifest in SIP.
• Findings challenge the exclusivity of self-disorders to endogenous psychosis, necessitating refined phenomenological assessment in early diagnosis.
• Longitudinal studies are required to determine if ASEs in SIP are transient or prodromal markers.