Occurrence of cardiorespiratory diseases and impact on lifespan in Swedish Irish Wolfhounds: a retrospective questionnaire-based study

Lovisa Orleifson, Ingrid Ljungvall, Katja Höglund, Jens Häggström

According to Swedish animal insurance data, Irish Wolfhounds (IW) are 29 times more likely to die from cardiac causes than the baseline breed. Dilated cardiomyopathy (DCM) has a high prevalence in the breed and the disease has been shown to be hereditary in IW. Few studies address respiratory diseases in IW, but reports suggest that the incidence of pneumonia is high. Respiratory diseases are reported as a common cause of death in the breed along with cardiac, neoplastic, musculoskeletal and gastrointestinal diseases. The aim of this study was to investigate mortality, morbidity and lifespan in Swedish IW through a questionnaire-based study. Focus was on DCM and pneumonia and potential association between these diseases. Questionnaires were sent to owners of purebred IW registered in the Swedish Kennel Club, born during 2006-2008. Owners were asked for information concerning occurrence of disease, results of clinical examinations, treatments, cause and date of death. Overall response rate was 38% (105 completed questionnaires). Median lifespan was 2720 days (7.5 years). Males had shorter lifespan than females (median 2523 and 2836 days, respectively), P = 0.02. The most common causes of death were neoplastic disease (24%), cardiac disease (18%) and respiratory disease (16%). The percentage of dogs with pneumonia on at least one occasion during their lifetime was 37%, with a majority experiencing recurrent episodes (53%). The median lifespan was shorter for dogs affected by pneumonia on at least one occasion (2629 days), compared to dogs without history of pneumonia (2804 days) (P = 0.04), whereas the lifespan did not differ between dogs with or without a diagnosis of DCM. No sex predisposition was found regarding DCM or pneumonia. This study showed that DCM and pneumonia are common conditions in IW in Sweden, and that dogs affected by pneumonia have a shorter lifespan than those without history of pneumonia. Considering the results from this study and previous studies regarding these diagnoses in IW; cardiac and respiratory disease should be given further attention in the course of improving the general health of the breed.