Incidence and risk factors associated with exertional rhabdomyolysis syndrome in National Hunt racehorses in Great Britain.

The research investigates the occurrence and related risk factors of exertional rhabdomyolysis syndrome, a condition characterized by muscle breakdown due to excessive physical effort, in National Hunt racehorses in Great Britain. It was conducted via a telephone survey and found that the syndrome’s incidence was 6.1 cases per 100 horses annually, with 55% of the racing yards reporting at least one case. Risk factors included the horse’s sex, length of training gallop, and type.

Research Methodology

• The researchers conducted a telephone survey of 51 National Hunt racing yards, encompassing 1140 horses under training, executed in April and May 2003. The aim of this survey was to determine the incidence of exertional rhabdomyolysis syndrome during the preceding year.
• A case-control study design was utilized in the research. Eight yards were selected for this study based on the criterion that they had confirmed cases of the syndrome, as verified through analyzing serum muscle enzymes.

Findings

• The combined incidence of the syndrome was noted to be 6.1 cases per 100 horses annually. Furthermore, 55% of surveyed racing yards reported dealing with at least one case.
• The researchers identified specific risk factors associated with the development of this syndrome. These included the horse’s sex, the average distance run during training (the training gallop), and the type of the horse, whether it was a steeplechaser, a bumper/unraced horse, or a hurdler.
• Interestingly, the study didn’t find any significant associations between the development of exertional rhabdomyolysis syndrome and the horse’s temperament, age, or Timeform rating (a system used to rate the performance of racehorses).

Conclusions

• The study provides valuable insights into the incidence and risk factors of exertional rhabdomyolysis syndrome in National Hunt racehorses.
• The results could aid in better understanding the syndrome’s prevalence amongst this group of horses and develop strategies to minimize its occurrence by paying attention to the identified risk factors.