A multi-centered case-control study of equine acute abdominal disease (colic)

Acute abdominal disease (colic) in horses is a disease syndrome characterized by the presence of abdominal pain. Colic is a leading cause of mortality and morbidity in horses. No large scale epidemiologic investigations have ever been performed to identify risk factors for equine colic. This dissertation identified risk factors for equine colic by means of a multi-centered, hospital-based case-control study. The first phase of the study involved a one-year pilot project of 300 horses admitted to the veterinary teaching hospital at the University of Pennsylvania. An extensive telephone questionnaire was used to collect information from owners, trainers and other care personnel. In the second phase of the project, a multi-centered study was undertaken at the university veterinary teaching hospitals of Cornell, Guelph, Ohio State, Pennsylvania, and Tufts. Four hundred and twelve colic cases were identified during the 10 month study period. An equal number of control subjects were randomly selected from the population of horses that were admitted to the hospitals for reasons other than colic. Risk factors were identified using multivariable logistic regression analysis. The following factors were found to be associated with an increased colic risk: Arabian horses, the amount of corn fed, and a history of previous colic episodes. The following factors were found to be associated with a decreased colic risk: access to two or three different pastures during the 4 week period prior to admission, the total intake of non-roughage (concentrate) feed, and the daily use of a pyrantel pamoate anthelmintic. The presence of significant interactions made it difficult to summarize the effects of institution, age, the type of person responsible for the day-to-day care of the horse, access to water on outside enclosures, and the presence of any recent health problem on the risk of colic. Overall these results point to a combination of intrinsic, management, dietary and parasitological factors being involved in the etiology of equine colic