Source: UNIVERSITY OF ILLINOIS submitted to NRP
EFFICACY OF GASTRIC ULCER PROPHYLAXIS IN HORSES EXPOSED TO MULTIPLE RISK FACTORS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
Reporting Frequency
Annual
Accession No.
1021612
Grant No.
(N/A)
Cumulative Award Amt.
(N/A)
Proposal No.
(N/A)
Multistate No.
(N/A)
Project Start Date
Dec 1, 2019
Project End Date
Sep 30, 2021
Grant Year
(N/A)
Program Code
[(N/A)]- (N/A)
Recipient Organization
UNIVERSITY OF ILLINOIS
2001 S. Lincoln Ave.
URBANA,IL 61801
Performing Department
Veterinary Research & Extension
Non Technical Summary
Equine gastric ulcer syndrome (EGUS) is a common and significant cause of morbidity in horses, with a range of clinical signs including inappetence, colic, and poor performance. EGUS has several known risk factors, including fasting and non-steroidal anti-inflammatory drug (NSAID) administration. Horses hospitalized for colic are commonly exposed to both of these risk factors, making these patients at particularly high risk for the formation of both squamous (associated with fasting) and glandular (associated with NSAIDs) gastric ulcers. Prophylactic treatment with anti-ulcer medication is often prescribed for these at-risk patients, but appropriate drug selection is complicated by the fact that squamous and glandular ulcers vary both in etiology and response to treatment. Additionally, treatment is costly (omeprazole) and/or time consuming (sucralfate, given three times daily) to administer, making selection of the most effective protocol for a horse's individual situation highly desirable. To our knowledge, evidence-based recommendations are not available for effective prevention of gastric ulceration in patients exposed to multiple risk factors. The aim of this study is to establish the efficacy of omeprazole or sucralfate monotherapy in the prevention of gastric ulceration resulting from the combined stressors of NSAID use and fasting, using an experimental model that mimics conditions commonly experienced by hospitalized equine colic patients. We hypothesize that prophylactic treatment with either omeprazole or sucralfate will be equally effective at the prevention of gastric ulceration in horses under these conditions. Twenty healthy adult horses will undergo a feed-fast protocol and be treated with flunixin meglumine during two seven-day treatment periods. Following a two-way randomized crossover block design, horses will receive either omeprazole (1mg/kg by mouth q24 hours), or sucralfate (20mg/kg by mouth q8 hours), with a minimum eight-week washout between treatments. Gastroscopy will be performed after each of three 24-hour fast periods to document presence and severity of both squamous and glandular gastric ulceration. Upon completion of this study, we expect to have established the utility (or not) of omeprazole and sucralfate for ulcer prophylaxis in fasted horses prescribed flunixin meglumine. This work is an important step towards the development of evidence-based recommendations for the prevention of gastric ulcers in clinical patients exposed to multiple risk factors.
Animal Health Component
50%
Research Effort Categories
Basic
50%
Applied
50%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
31138101060100%
Knowledge Area
311 - Animal Diseases;

Subject Of Investigation
3810 - Horses, ponies, and mules;

Field Of Science
1060 - Biology (whole systems);
Goals / Objectives
Establish the efficacy of omeprazole or sucralfate monotherapy in the preventionof gastric ulceration resulting from the combined stressors of NSAID use and fasting. We havefound that the combination of a feed-fast protocol and flunixin meglumine administration rapidly induces clinically significant (≄ grade 2) glandular and squamous gastric ulcers. In this objective, horses will serve as their own controls following a two-way crossoverdesign, with a minimum eight-week washout period between treatments. Horses will receive either omeprazole (1mg/kg by mouth [PO] q24 hours; Treatment A), or sucralfate (20mg/kg PO q8 hours;Treatment B). Based upon the reliable and severe gastric ulceration induced in our preliminarywork and previously published studiesinclusion of an untreated control group is unnecessary,as the focus of the proposed work is to directly compare efficacy of the two prophylactictreatments. Gastroscopy will be performed following a 24-hour fast on days 2, 4, and 7 of eachtreatment period to document presence and severity (graded 0-4) of both squamous and glandulargastric ulceration.
Project Methods
Twenty healthy horses from the teaching herd maintained at the University of Illinois Veterinary Teaching Hospital (VTH) will be used in a randomized crossover design. Each horse will be kept in a stall with timothy grass/alfalfa mixed hay fed twice daily and water available at all times. Prior to the study and between treatment phases, horses will be maintained on pasture with intermittent stabling as needed. For the study protocol, horses will be placed on a feed-fast protocol to induce gastric ulcers: 24h fast - 24h feed - 24h fast - 48h feed - 24h fast. Starting at the time of the first gastroscopy exam, immediately following the first fasting period, horses will treated with 1.1 mg/kg flunixin meglumine IV via jugular catheter. This treatment will be continued every 12 hours throughout the study protocol period. To evaluate the efficacy of each ulcer prophylaxis protocol, horses will serve as their own controls following a two-way crossover design. Under Treatment A, horses will be administered the labeled preventative dose of omeprazole (GastroGardĀ®, 1mg/kg PO q24 hours) for fivedays, beginning after the initial 24-hour period of fasting and first gastroscopy exam. Omeprazole will be administered 30 minutes prior to a hay meal. Under Treatment B, horses will be administered sucralfate (20mg/kg PO q8 hours) for fivedays, beginning after the initial period of fasting and first gastroscopy exam. The order of the treatment protocols will be randomized according to a Latin Square design. At the completion of each protocol period, horses will be turned out on pasture or otherwise returned to their typical housing environment for at least eightweeks before starting the next protocolGastroscopy will be performed threetimes during each trial: 1) after the initial 24 hours of fasting, establishing a baseline; 2) after 48 cumulative hours of fasting/48 cumulative hours of medication; and 3) after 72 cumulative hours of fasting/120 cumulative hours of medication. Gastroscopy with a 3.5m video endoscope will be performed using routine restraint and standing sedation. Endoscopy images will be reviewed and scored by an investigator blinded to treatment at the conclusion of the study. Complete physical examinations will be performed prior to initiation and twice daily during each protocol. During each study protocol period, horses will be monitored every sixhours by study personnel; attitude, appetite, water consumption, and manure production will be recorded. Every 48 hours PCV, TS, lactate, glucose, and a renal profile will be measured to monitor hydration, NSAID-induced renal injury and colon inflammation. Scanning ultrasounds of the abdomen will be performed at the time of each gastroscopy, with particular emphasis on the kidneys and large colon. Subjective assessments will be made of kidney structure and colonic edema, and objective measurements will be taken of the right dorsal colon wall thickness.

Progress 12/01/19 to 09/30/21

Outputs
Target Audience:Equine gastric ulcer syndrome is a common and significant cause of morbidity in horses, with a range of potential clinical signs including inappetence, colic, and poor performance. Gastric ulceration is of particular concern in critically ill patients, which are considered to be predisposed to this complication. Prevention of gastric ulceration when known risk factors are present can mitigate the physical, emotional, and financial impacts of this disease. The results of this project will directly impact both horse owners and veterinarians. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?This project comprised a major portion of the MS thesis for the primary author, Dr. Bishop. How have the results been disseminated to communities of interest?The results of this study will be presented in abstract form at the American College of Veterinary Surgeons annual meeting in October of 2021. Further, a manuscript submitted to the Equine Veterinary Journal is in final revisions with the journal editor. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Horses (n=14) received either omeprazole (1 mg/kg PO q24h) or sucralfate (20 mg/kg PO q8h) while undergoing the feed-fast/NSAID protocol, allowed an eight-week washout period, and then administered the alternate treatment. Serial gastroscopy, ultrasound, and hematology documented treatment effects. ESGD and EGGD worsened over time under both treatments. There was a significant effect of treatment on EGGD scores (p<0.001), with post-treatment EGGD scores higher for horses receiving sucralfate (median 3; IQR 2.25,3) than omeprazole (1; 1,1). The effect of treatment on ESGD scores just achieved significance (p=0.05), with post-treatment ESGD scores higher for sucralfate (4; 3,4) than omeprazole (2; 2,3). The main limitation of this study was that it was performed in healthy horses, and response to treatment may differ in horses with clinical illness. Additional investigation in a larger population may be required to detect significant differences in other clinical parameters. The primary aim of this study was to evaluate the efficacy of omeprazole and sucralfate as a single therapy for the prevention of EGUS in fasted horses treated with NSAIDs. ESGD and EGGD developed or worsened over time under both treatments. Omeprazole was more effective than sucralfate for mitigating the development of ESGD and EGGD formation. Additionally, horses developed intestinal thickening while receiving sucralfate, but not omeprazole. Of the two gastroprotectant medications studied, omeprazole should be considered for mitigation of EGUS in horses exposed to the dual risk factors of fasting and flunixin meglumine administration. Further study of naturally occurring EGUS progression in clinical patients and efficacy of omeprazole and sucralfate in a clinical setting is warranted.

Publications

  • Type: Journal Articles Status: Under Review Year Published: 2022 Citation: Bishop, R.C., Kemper, A.M., Wilkins, P.A. and McCoy, A.M. 2022. Effect of omeprazole and sucralfate on gastrointestinal injury in a fasting/NSAID model. Equine Vet J. In Final Revisions.
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2021 Citation: Bishop, R.C., Kemper, A.M., Wilkins, P.A. and McCoy, A.M. 2021. Omeprazole reduced severity of gastric and colonic morbidity induced by combined fasting/NSAID model in healthy horses compared to sucralfate. American College of Veterinary Surgeons Surgical Summit, Chicago, IL, October 2021.


Progress 12/01/19 to 09/30/20

Outputs
Target Audience: Nothing Reported Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?This project comprises the major portion of graduate research training for an equine surgery resident. How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals?After completion of data analysis, results will be disseminated to the veterinary community and equine industry through appropriate channels.

Impacts
What was accomplished under these goals? The experimental portion of this project has ended, with 14 horses successfully completing both treatment armsof this crossover design. Preliminary data analysis suggest that there was a significant difference between treatments, but final analysis is ongoing.

Publications