Bodyweight change aids prediction of survival in chronic equine grass sickness.
Authors: Jago R C, Handel I, Hahn C N, Pirie R S, Keen J A, Waggett B E, McGorum B C
Journal: Equine veterinary journal
Summary
# Editorial Summary: Bodyweight Change as a Prognostic Indicator in Chronic Equine Grass Sickness Chronic grass sickness remains a devastating condition with limited objective prognostic tools; this retrospective analysis of 213 cases hospitalised between 1998 and 2013 investigated whether bodyweight dynamics during treatment could predict survival outcomes. Researchers tracked percentage bodyweight loss across multiple time intervals (7-day intervals up to 28 days and cumulative periods) in survivors versus non-survivors, generating survival probability curves based on weight change parameters. Survivors exhibited significantly lower median maximum bodyweight loss (5.9% of admission weight) compared with non-survivors (12.7%), a difference maintained consistently across all measured timepoints, though neither the rate of loss nor the total magnitude was independently more predictive than the other. The findings suggest that serial bodyweight monitoring offers clinicians quantifiable data to improve prognostic discussions with owners, yet acknowledge that predictive accuracy remains insufficient for definitive individual case decision-making. For practitioners managing chronic grass sickness cases, regular bodyweight assessment provides an objective, practical monitoring tool that, whilst not deterministic, may usefully inform realistic prognostic expectations and help distinguish between cases with genuinely improving trajectories and those trending towards poorer outcomes.
Read the full abstract on PubMed
Practical Takeaways
- •Monitor bodyweight changes during hospitalization for chronic grass sickness cases—slower weight loss and lower total weight loss correlate with better survival outcomes
- •Use survival prediction curves as a prognostic aid for owner discussions, but recognize that weight loss data alone cannot definitively determine individual case outcomes
- •Track weight loss rates over 7-day intervals; the rate of loss is as predictive as total loss, so early intervention may influence trajectory
Key Findings
- •Survivors had significantly lower median maximum bodyweight loss (5.9%) compared to nonsurvivors (12.7%) during hospitalization
- •Both rapidity and magnitude of bodyweight loss were equally predictive of survival outcome
- •Survivors and nonsurvivors showed comparable maximum individual weight losses (36% vs 37%), suggesting magnitude alone is insufficient for prediction
- •Survival prediction curves based on percentage weight change provide objective data to aid prognosis discussion but lack specificity for individual case decision-making