A survey of horse owners in Great Britain regarding horses in their care. Part 2: Risk factors for recurrent airway obstruction.

Authors: Hotchkiss J W, Reid S W J, Christley R M

Journal: Equine veterinary journal

DOI: 10.2746/042516407x180129 PubMed: 17722720Log in to save

Summary

# Recurrent Airway Obstruction in British Horses: Prevalence and Risk Factors Recurrent airway obstruction (RAO) remains a common but under-investigated respiratory condition in British horses despite its generally reversible and manageable nature. Hotchkiss and colleagues surveyed over 3,000 horse owners across Great Britain using a standardised risk-screening questionnaire, employing two-stage cluster sampling via veterinary practices and multilevel logistic regression analysis to identify disease associations. The study established RAO prevalence at 14.0% (95% CI 10.7–17.4%) in the general horse population, substantially higher than previously recognised, with advancing age and urbanised environments emerging as significant management-related risk factors. Early-life exposures—particularly to hay and respiratory infections—were independently associated with later RAO development, suggesting that respiratory system challenges during maturation may predispose horses to chronic obstructive airway disease. For equine professionals, these findings underscore the importance of optimising air quality and respiratory health during a horse's formative years, whilst recognising that urban-based management practices and air pollution warrant closer scrutiny as potential disease modifiers in mature animals.

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Practical Takeaways

•RAO affects approximately 1 in 7 horses in Great Britain; practitioners should screen middle-aged and older horses, particularly those in urban settings, for signs of airway obstruction
•Early-life respiratory health management and hay exposure during development may influence RAO risk, suggesting preventive strategies in young horses could reduce disease incidence
•Management practices in urbanised environments may need review as they appear associated with higher RAO prevalence, whether through air quality, housing, or other factors

Key Findings

•Estimated prevalence of RAO in Great Britain horse population was 14.0% (95% CI 10.7-17.4%)
•Increasing age and exposure to urbanised environment were identified as significant risk factors for RAO
•Exposure to hay and respiratory infection in early life were associated with development of RAO later in life
•RAO represents a significant health problem in the British horse population requiring epidemiological investigation

Conditions Studied

recurrent airway obstruction (rao)

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