Altered Gastrointestinal Interoception in Anorexia Nervosa Predicts Relapse.

Area of Science:

• Neuroscience
• Gastroenterology
• Psychiatry

Background:

• Anorexia nervosa (AN) is a severe psychiatric disorder with high relapse rates.
• Current recovery tracking lacks objective biomarkers.
• Gastrointestinal interoception is disrupted in AN, but not clinically assessed.

Purpose of the Study:

• To investigate gastrointestinal interoception deficits in AN.
• To identify objective biomarkers for AN relapse and symptom severity.
• To explore computational mechanisms underlying interoceptive dysfunction in AN.

Main Methods:

• Single-blind, randomized-crossover study with 62 AN patients and 57 controls.
• Ingestible vibrating capsule task to assess gastrointestinal detection.
• Simultaneous recording of behavioral, EEG, and physiological signals.
• Computational modeling of interoceptive processing.

Main Results:

• AN participants exhibited reduced perceptual accuracy and higher miss-rates in gut sensation detection.
• Computational models showed stronger prior beliefs against gut sensations and diminished interoceptive precision in AN.
• Capsule stimulation induced greater hunger increases in AN patients.
• Predictors of relapse included initial priors, response bias, and stomach unpleasantness.
• Miss-rate and precision shifts predicted symptom severity.

Conclusions:

• Mechanistic disruptions in gastrointestinal interoception are identified in AN.
• These disruptions serve as predictive biomarkers for relapse and symptom severity.
• Scalable biomarkers can personalize AN treatment and prevent recurrence.