Fear, Gastrointestinal Distress, and Interoception: Physiological and Psychological Mechanisms in Eating Disorders

The proposed study tests fear, gut peptide response, and perceptions of fullness as causes of gastrointestinal distress and eating disorder maintenance.

Study Overview

• Status: Completed
• Conditions: Feeding and Eating Disorders
• Intervention / Treatment: Other: Test meal description changed

• Study Type: Interventional
• Enrollment (Actual): 133
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Ohio
    • Athens, Ohio, United States, 45701
      • Ohio University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 40 years (Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• female
• DSM-5 eating disorder
• score 16 or higher on the Clinical Impairment Assessment
• experience nausea or stomachache after eating at least "sometimes"
• 18 to 40 years old
• body mass index between 18.5 and 26.5 kg/m2

Exclusion Criteria:

• medical conditions affect appetite or weight
• Recent pregnancy or current breastfeeding
• Dairy, strawberry or honey food allergy
• Specific phobia, blood-injection-injury type

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: High Fat Yogurt - Low Fat Yogurt; Participants will eat yogurt described as 'high fat' at Study Visit 2 and yogurt described as 'low fat' at Study Visit 3.	Other: Test meal description changed; Using a within-subjects crossover design, on two separate mornings participants will eat yogurt described as 'high fat' and 'low fat.' In actuality, the meals will not differ.
Other: Low Fat Yogurt - High Fat Yogurt; Participants will eat yogurt described as 'low fat' at Study Visit 2 and yogurt described as 'high fat' at Study Visit 3.	Other: Test meal description changed; Using a within-subjects crossover design, on two separate mornings participants will eat yogurt described as 'high fat' and 'low fat.' In actuality, the meals will not differ.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Subjective Rating of Fear	Area under the curve with respect to increase (AUCi) from the 10 minutes period prior to the meal until immediately after the meal will be used to characterize changes in Visual Analogue Scale ratings of momentary fear ranging from "Not at All (0)" to "Extreme (100)." AUCi was calculated as: (((Fear at -10 minutes)+ (Fear at 0 minutes))*10/2) + (((Fear at 0 Minutes)+(Fear at +10 minutes))*10/2) - (Fear at -10 minutes)*20. A more positive score indicates greater increases in fear over the pre to post meal period.	-10 minutes, 0 minutes (immediately after the intervention), and 10 minutes post-intervention
Difference in Average Skin Conductance	Skin conductance data will be collected in microsiemens using a Biopac Bionomadix EDA System during the period before and after the test meal. The difference in average microsiemens will be computed for each test meal using the following equation: (Average activity for the 10 minute meal period) - (average activity for the 10 minutes prior to the meal). A higher difference indicates increased physiological activation during the meal period relative to the pre-meal period.	-10 minutes, 0 minutes (immediately after the intervention), and 10 minutes post-intervention
Gastrointestinal Distress	Gastrointestinal distress will be the averaged visual analogue scale ratings of "Nausea" and "Stomach Ache" ranging from "Not At All (0)" to "Extreme (100)." Area under the curve with respect to increase (AUCi) from the 10 minutes period prior to the meal until immediately after the meal will be used to characterize changes gastrointestinal distress. AUCi was calculated as: (((Gastrointestinal distress at -10 minutes)+ (Gastrointestinal distress at 0 minutes))*10/2) + (((Gastrointestinal distress at 0 Minutes)+(Gastrointestinal distress at +10 minutes))*10/2) - (Gastrointestinal distress at -10 minutes)*20. A more positive score indicates greater increases in gastrointestinal distress over the pre to post meal period.	-10 minutes, 0 minutes (immediately after the intervention), and 10 minutes post-intervention
Cholecystokinin Response	Blood was drawn repeatedly. Cholecystokinin (CCK) values in plasma were quantified in ng/mL using a commercially available enzyme immunoassay (Phoenix Pharmaceuticals EK-069-02). Area under the curve with respect to increase (AUCi) was calculated from the time period immediately before the test meal to 90 minutes after the test meal. AUCi was calculated as: (((CCK at 0 Minutes)+( CCK at +10 minutes))*10/2) + (((CCK at 10 Minutes)+( CCK at +20 minutes))*10/2) + (((CCK at 20 Minutes)+( CCK at +30 minutes))*10/2) + (((CCK at 30 Minutes)+( CCK at +60 minutes))*30/2) + (((CCK at+ 60 Minutes)+( CCK at +90 minutes))*30/2) - (CCK at -10 minutes)*90. A more positive score indicates greater increases in CCK over the pre to post meal period.	0 minutes (immediately after the intervention), 10 minutes, 20 minutes, 30 minutes, 60 minutes and 90 minutes post-intervention
Peptide YY Response	Blood was drawn repeatedly. Peptide YY (PYY) values in plasma were quantified in ng/mL using a commercially available enzyme immunoassay (Phoenix Pharmaceuticals EK-059-02). Area under the curve with respect to increase (AUCi) was calculated from the time period immediately before the test meal to 90 minutes after the test meal. AUCi was calculated as: (((PYY at 0 Minutes)+( PYY at +10 minutes))*10/2) + (((PYY at 10 Minutes)+(PYY at +20 minutes))*10/2) + (((PYY at 20 Minutes)+( PYY at +30 minutes))*10/2) + (((PYY at 30 Minutes)+( PYY at +60 minutes))*30/2) + (((PYY at+ 60 Minutes)+( PYY at +90 minutes))*30/2) - (PYY at -10 minutes)*90. A more positive score indicates greater increases in PYY over the pre to post meal period.	0 minutes (immediately after the intervention), 10 minutes, 20 minutes, 30 minutes, 60 minutes and 90 minutes post-intervention
Subjective Rating of Fullness	Fullness will be the averaged visual analogue scale ratings of "full" and "satiated(satisfied)" ranging from "Not At All (0)" to "Extreme (100)." Area under the curve with respect to increase (AUCi) will be used to characterize changes in fullness from immediately before the test meal to 90 minutes after. AUCi was calculated as: (((Fullness at -10 minutes)+ (Fullness at 0 minutes))*10/2) + (((Fullness at 0 Minutes)+( Fullness at +10 minutes))*10/2) + (((Fullness at 10 Minutes)+( Fullness at +20 minutes))*10/2) + (((Fullness at 20 Minutes)+( Fullness at +30 minutes))*10/2) + (((Fullness at 30 Minutes)+( Fullness at +60 minutes))*30/2) + (((Fullness at 60 Minutes)+( Fullness at +90 minutes))*30/2) - (Fullness at -10 minutes)*100. A more positive score indicates greater increases in fullness over the pre to post meal period.	0 minutes (immediately after the intervention), 10 minutes, 20 minutes, 30 minutes, 60 minutes and 90 minutes post-intervention
Urges to Restrict Food Intake	Visual analogue scales will assess momentary "urge to restrict" from "Not At All" (0) to "Extreme" (100). The 60 minute assessment will be used for the exploratory serial mediation model.	60 minutes post-intervention

Collaborators and Investigators

• Sponsor: Ohio University
• Collaborators: National Institute of Mental Health (NIMH)
• Investigators: Principal Investigator: Katherine J Forney, PhD, Ohio University

Study record dates

Study Major Dates

• Study Start (Actual): April 22, 2022
• Primary Completion (Actual): March 20, 2025
• Study Completion (Actual): March 20, 2025

Study Registration Dates

• First Submitted: May 11, 2022
• First Submitted That Met QC Criteria: May 16, 2022
• First Posted (Actual): May 19, 2022

Study Record Updates

• Last Update Posted (Actual): April 15, 2026
• Last Update Submitted That Met QC Criteria: March 26, 2026
• Last Verified: January 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Mental Disorders; Signs and Symptoms, Digestive; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Feeding and Eating Disorders
• Other Study ID Numbers: 21-F-14; R15MH128703 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Data will be shared according to the NIMH Data Sharing Policy (NOT-MH-19-033), including being shared with the NIMH Data Archive.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No