Mortality of Swedish horses with complete life insurance between 1997 and 2000: variations with sex, age, breed and diagnosis.

The research studied the effectiveness of data from Swedish insurance company, Agria, for providing statistics on horse mortality by considering factors such as sex, age, breed, and diagnosis. The study looked at horses with complete life insurance between 1997 and 2000.

Mortality Rate Calculation

• This study aimed to provide mortality statistics on Swedish horses. The mortality incident and survival rates were computed crudely and then stratified based on factors including sex, age, breed, breed group, and diagnosis.
• The focus was on horses fully insured by Agria, a Swedish insurance company. This comprehensive insurance covers most health problems horses might encounter.
• The total mortality rate identified 415 deaths per 10,000 horse-years at risk, considering a 95% confidence interval of 399 to 432 deaths. This number is a scale used by researchers to measure mortality in a way that accounts for horses’ age differences and the period under study.

Variation in Mortality Rates

• The mortality rate that considered only diagnosed cases was 370 deaths per 10,000 horse-years at risk, with a 95% confidence interval of 355 to 386 deaths.
• The study found variations in mortality rates based on the horse’s sex – the diagnostic mortality of geldings was 459, mares 345, and stallions 214 per 10,000 horse-years at risk, again considering 95% confidence intervals.
• Mortality rates increased with age and differed significantly between breeds, indicating age and breed as essential factors in determining horse mortality.

The Cause of Death and Survival Analysis

• Survival analysis showed that the median age at death for horses insured before they were one year old was 18.8 years.
• Joint problems were identified as the most common cause of death or euthanasia, accounting for 140 out of 10,000 horse-years at risk.
• The results of multivariable models constructed using Poisson regression were generally in good agreement with the crude results, validating the statistical analysis’ effectiveness.

In conclusion, the study appears to affirm the usefulness of Agria’s database for acquiring horse mortality statistics. The data can facilitate a better understanding of horse mortality and provide valuable insights for horse care.