Identifying Multidimensional Signatures of Gastric Interoception in Functional Dyspepsia

Participant Inclusion Criteria--

Functional Dyspepsia Group:

• Males and females; ages 18-65 years
• Rome V functional dyspepsia post-prandial distress syndrome subtype
• Negative upper endoscopy or upper GI series to rule out structural/organic cause for FD
• greater than or equal to 5.5 gut interoceptive awareness score (by VSI awareness subscale)
• Fluent in English
• Willing and able to provide informed consent
• Stable dose for 30 days prior to Visit 1 if on a neuropsychiatric medication (e.g., TCA, SNRI, SSRI mirtazapine, atypical antipsychotic, gabapentin, buspirone, pregabalin)
• No current plans to initiate a new or change dosing on a neuropsychiatric medication within the study period

Anorexia Nervosa Group:

• Males and females; ages 18-65 years
• DSM-5 anorexia restricting-type by the Eating Disorder Module in the Diagnostic Interview for Mood, Anxiety, and OCD and related Neuropsychiatric Disorders (DIAMOND)
• greater than or equal to 5.5 gut interoceptive awareness score (by VSI awareness subscale)
• Fluent in English
• Willing and able to provide informed consent
• Stable dose for 30 days prior to Visit 1 if on an SSRI
• No current plans to initiate a new neuromodulator
• No current plans to initiate a new SSRI or change dosing on an SSRI

Healthy Controls:

• Males and females; ages 18-65 years
• BMI greater than or equal to 18.5 kg/m2
• Fluent in English
• Willing and able to provide informed consent

Participant Exclusion Criteria--

Functional Dyspepsia Group:

• Presence of other conditions that could explain the patient's symptoms by medical chart:

• Pyloric or intestinal obstruction (by EGD, UGI, or Abdominal CT)
• Active H.pylori (by CLO test or stool antigen test)
• Active inflammatory bowel disease
• Eosinophilic gastroenteritis or eosinophilic esophagitis
• Acute renal failure
• Chronic renal failure (serum creatinine >3 mg/dL) and/or on hemodialysis or peritoneal dialysis
• Acute liver failure
• Any acute gastrointestinal process
• Any plausible structural or metabolic causes
• Heartburn as predominant symptom
• History of peptic ulcer
• Symptom resolution with antisecretory therapy (PPI use for other reasons that did not resolve FD symptoms will be allowed)
• Endorses any contraindications to MRI
• Body weight of 450 lbs or greater or BMI of 50 kg/m2 or greater (limit of MRI table)
• Allergy to pineapple (used in the test meal during MRI)
• History of GI tract surgery or any serious medical condition (e.g., cancer)
• Pregnancy/breastfeeding within the last 8 weeks
• Uncontrolled diabetes (indicated by HbA1c greater than or equal to 7%) by chart
• Narcotic analgesics greater than three days per week
• Cannabinoid use greater than three days per week
• Intellectual disability by history
• Illiteracy
• History of weight/shape-based eating disorder including anorexia nervosa by DIAMOND
• Current binge eating by DIAMOND
• Current self-induced vomiting by DIAMOND
• Current laxative or diuretic misuse by DIAMOND
• Current substance/alcohol use disorder within past year by DIAMOND
• Current/history of psychosis by DIAMOND
• Current mania by DIAMOND
• Active suicidal ideation by modified DIAMOND abbreviated suicide module; passive suicidal ideation is allowed
• Inability or unwillingness to consume food by mouth
• Inability to provide informed consent

Anorexia Nervosa Group:

• Diagnosis of chronic gastrointestinal disorder
• Rome V functional dyspepsia
• Endorses any contraindications to MRI
• Body weight of 450 lbs or greater or BMI of 50 kg/m2 or greater (limit of MRI table)
• Allergy to pineapple (used in the test meal during MRI)
• History of GI tract surgery or any serious medical condition (e.g., cancer)
• Pregnancy/breastfeeding within the last 8 weeks
• Uncontrolled diabetes (indicated by HbA1c greater than or equal to 7%) by chart
• Narcotic analgesics greater than three days per week
• Cannabinoid use greater than three days per week
• Intellectual disability by history
• Illiteracy
• Current binge eating by DIAMOND
• Current self-induced vomiting by DIAMOND
• Current laxative or diuretic misuse by DIAMOND
• Current substance/alcohol use disorder within past year by DIAMOND
• Current/history of psychosis by DIAMOND
• Current mania by DIAMOND
• Active suicidal ideation by DIAMOND abbreviated suicide module; passive suicidal ideation is allowed
• Inability or unwillingness to consume food by mouth
• Inability to provide informed consent
• Current use of neuropsychiatric medication other than an SSRI (e.g., TCA, SNRI, mirtazapine, atypical antipsychotic, gabapentin, buspirone, pregabalin)

Healthy Controls:

• Diagnosis of chronic gastrointestinal or pain disorder
• Rome V functional dyspepsia
• greater than or equal to 5.5 gut interoceptive awareness score (by VSI awareness subscale)
• Current use of a medication known to influence gastric sensorimotor functions (including neuromodulators and SSRIs)
• Active psychiatric disorder including a feeding/eating disorder by DIAMOND
• Endorses any contraindications to MRI
• Body weight of 450 lbs or greater or BMI of 50 kg/m2 or greater (limit of MRI table)
• Allergy to pineapple (used in the test meal during MRI)
• History of GI tract surgery or any serious medical condition (e.g., cancer)
• Pregnancy/breastfeeding within the last 8 weeks
• Uncontrolled diabetes (indicated by HbA1c greater than or equal to 7%) by chart
• Narcotic analgesics greater than three days per week
• Cannabinoid use greater than three days per week
• Intellectual disability by history
• Illiteracy
• Current binge eating by DIAMOND
• Current self-induced vomiting by DIAMOND
• Current laxative or diuretic misuse by DIAMOND
• Current substance/alcohol use disorder within past year by DIAMOND
• Current/history of psychosis by DIAMOND
• Current mania by DIAMOND
• Active suicidal ideation by DIAMOND modified suicide module; passive suicidal ideation is allowed
• Inability or unwillingness to consume food by mouth
• Inability to provide informed consent