Taking a Deeper Dive Into OSFED Subtypes: A Meta-Analysis and Systematic Review.

Area of Science:

• Psychiatry
• Clinical Psychology
• Eating Disorders Research

Background:

• Eating disorders (EDs) encompass a range of conditions, including full-threshold diagnoses and Other Specified Feeding or Eating Disorders (OSFED).
• OSFED includes diverse presentations like atypical anorexia nervosa (AN), purging disorder (PD), night eating syndrome (NES), and subthreshold presentations of bulimia nervosa (sub-BN) and binge-eating disorder (sub-BED).
• Understanding the psychopathological severity of OSFED compared to full-threshold EDs and control groups (CGs) is crucial for accurate diagnosis and treatment.

Purpose of the Study:

• To systematically compare OSFED groups, including specific subtypes, with full-threshold EDs and CGs.
• To evaluate eating and general psychopathology across different ED classifications.
• To determine the clinical significance and severity of OSFED presentations.

Main Methods:

• A comprehensive literature search was conducted across major databases (PsycINFO, Medline, Embase, CINAHL) for studies published between January 2013 and February 2024.
• Studies meeting DSM-5 diagnostic criteria, assessed via clinical interviews or validated tools, were included.
• Quality appraisal using an adapted Downs and Black checklist and PROSPERO registration (ID: CRD42022314495) were performed.

Main Results:

• Meta-analyses of 33 studies revealed that combined OSFED and specific subtypes (atypical AN, NES) exhibited comparable eating psychopathology to full-threshold EDs.
• Individuals with OSFED demonstrated similar levels of eating and general psychopathology to full-threshold EDs, but significantly higher levels than CGs.
• Atypical AN and NES were specifically identified as having comparable severity to full EDs, while evidence for sub-BN and sub-BED was limited.

Conclusions:

• Findings support the conceptualization of atypical AN and NES as clinically significant eating disorders.
• These OSFED subtypes present with a severity comparable to full-threshold eating disorders.
• Further research is needed to clarify the psychopathology of subthreshold presentations like sub-BN and sub-BED.