Abstract
Abstract
Background: The Equine Injury Database (EID) is a census-level record of Thorough-bred racing in North America, currently recording 95.6% of all race starts in 2023,along with partial training and veterinary histories of each horse.
Objectives: To identify horse-, race- and track-level risk factors associated with race-related fatal musculoskeletal injury (MSI) of Thoroughbred racehorses in NorthAmerica.
Study Design: Retrospective cohort study.
Methods: The study cohort included all race starts made by horses born after31 December 2006, at tracks that fully report to the EID and consisted of 3,851,659race starts made by 250,840 Thoroughbred racehorses (median [IQR] starts per horse11 [5–22]) at 115 racetracks in the USA and Canada between 2009 and 2023, inclu-sive. Ninety-seven potential risk factors were investigated using univariable and mul-tivariable logistic regression modelling.
Results: Exactly 5733 fatal MSIs were recorded, an incidence of 1.49 fatal MSIs per1000 starts. Twenty risk factors had statistically significant associations withincreased or decreased odds of fatal MSI. Previously unidentified risk factorsincluded claiming race-related variables and void claim rules (VCR). Horses racing asclaimers were at increased odds compared with those who were not (odds ratio 1.31,95% confidence interval 1.19–1.45, p < 0.001 for the lowest claim prices). Starts inraces with the strictest VCR were at reduced odds compared with starts in races withno VCR (OR 0.76 [0.67–0.85], p < 0.001).
Main Limitations: Availability of new data sources increased substantially during the15-year time period of the study, meaning some new risk factors are limited in scopecompared with others.
Conclusions: Thoughtful integration of new data sources with race-level data canlead to new insights into risk factors for deleterious outcomes affecting racehorses.Results can inform ongoing efforts to mitigate the risk of fatal MSI, through directregulatory intervention and through building a risk profile based on individual historyand track-level factors.
Background: The Equine Injury Database (EID) is a census-level record of Thorough-bred racing in North America, currently recording 95.6% of all race starts in 2023,along with partial training and veterinary histories of each horse.
Objectives: To identify horse-, race- and track-level risk factors associated with race-related fatal musculoskeletal injury (MSI) of Thoroughbred racehorses in NorthAmerica.
Study Design: Retrospective cohort study.
Methods: The study cohort included all race starts made by horses born after31 December 2006, at tracks that fully report to the EID and consisted of 3,851,659race starts made by 250,840 Thoroughbred racehorses (median [IQR] starts per horse11 [5–22]) at 115 racetracks in the USA and Canada between 2009 and 2023, inclu-sive. Ninety-seven potential risk factors were investigated using univariable and mul-tivariable logistic regression modelling.
Results: Exactly 5733 fatal MSIs were recorded, an incidence of 1.49 fatal MSIs per1000 starts. Twenty risk factors had statistically significant associations withincreased or decreased odds of fatal MSI. Previously unidentified risk factorsincluded claiming race-related variables and void claim rules (VCR). Horses racing asclaimers were at increased odds compared with those who were not (odds ratio 1.31,95% confidence interval 1.19–1.45, p < 0.001 for the lowest claim prices). Starts inraces with the strictest VCR were at reduced odds compared with starts in races withno VCR (OR 0.76 [0.67–0.85], p < 0.001).
Main Limitations: Availability of new data sources increased substantially during the15-year time period of the study, meaning some new risk factors are limited in scopecompared with others.
Conclusions: Thoughtful integration of new data sources with race-level data canlead to new insights into risk factors for deleterious outcomes affecting racehorses.Results can inform ongoing efforts to mitigate the risk of fatal MSI, through directregulatory intervention and through building a risk profile based on individual historyand track-level factors.
| Original language | English |
|---|---|
| Pages (from-to) | 1-11 |
| Number of pages | 11 |
| Journal | Equine Veterinary Journal |
| Early online date | 25 Mar 2025 |
| DOIs | |
| Publication status | E-pub ahead of print - 25 Mar 2025 |
Bibliographical note
Publisher Copyright:© 2025 The Author(s). Equine Veterinary Journal published by John Wiley & Sons Ltd on behalf of EVJ Ltd.