Cause of Death by Breed

In this retrospective study, the Veterinary Medical Database (VMDB) was searched for breed-, age-, and size-specific causes of death between 1984 and 2004. A total of 80,306 dogs met inclusion criteria. After eliminating deaths classified as “unknown,” “dead on arrival,” “healthy,” or “euthanized,” a total of 74,566 records were available for analysis. The breed, age, and size were recorded, along with cause of death due to organ system (OS) or pathophysiologic process (PP). Breed-based analyses were conductedonly when there were ≥ 100 representatives in the group in order to reduce sampling error. The highest relative proportion of death by breed for the various OSs were gastrointestinal (GI) (Great Dane, Gordon setter, Akita, Chinese shar-pei, Weimaraner), cardiovascular (Newfoundland, Maltese, Chihuahua, Doberman pinscher, fox terrier), neurologic (dachshund, miniature dachshund, pug, miniature pinscher, Boston terrier), musculoskeletal (Saint Bernard, Great Pyrenees, Irish wolfhound, Great Dane, Greyhound), and respiratory (bulldog, borzoi, Yorkshire terrier, Afghan hound, treeing walker coonhound). Urogenital disease was not a major cause of death overall but was most common in the following breeds: Scottish terrier, Airedale terrier, dalmatian, Norwegian elkhound, standard schnauzer. The relative highest proportion of death by breed for PP were neoplasia (Bernese mountain dog, golden retriever, Scottish terrier, Bouvier des Flandres, boxer), infectious diseases (treeing walker coonhound, American Staffordshire terrier, greyhound, English pointer, Cardigan Welsh corgi), congenital (Newfoundland, bulldog, Akita, Yorkshire terrier, Maltese), and trauma (Australian heeler, American Staffordshire terrier, Jack Russell terrier, miniature pinscher, Australian shepherd). The most common causes of death in young dogs as categorized by OS were GI and infectious with a marked shift toward neurologic and neoplastic disease as dogs aged. With age, risk for death from cardiovascular, endocrine, neurologic, or urogenital disease increased but risk for death from musculoskeletal or hematopoietic causes did not. When categorized by PP, trauma was the most common cause of death in young dogs, with risk for death due to neoplasia increasing with age. Larger dogs died more frequently of musculoskeletal or GI diseases and small-breed dogs died more commonly of endocrine causes. Smaller breeds were more likely to die of degenerative and metabolic causes whereas larger dogs succumbed more frequently to neoplastic disease.

Commentary: This was an impressive study because of the large population and number of breeds involved. It is important to note several biases in the study. First, the dogs presented to veterinary medical hospitals; results might differ if data had been collected from primary care practices. Second, the study spanned 20 years and over that period there has been great progress in veterinary medicine. Disease incidence might differ if the study had been conducted in a more recent period. Third, this is a retrospective study and, while the authors took great pains to collect data, they ultimately had to rely on what was reported in the records. The major take-home points are that GI and infectious diseases were significant risk factors for death in young dogs. Large dogs were at greater risk for death due to musculoskeletal and GI diseases and smaller breeds had an increased risk for endocrine diseases. Trauma was a huge risk for young dogs and neoplasia for older dogs. Finally, some diseases may be the result of selective breeding for certain characteristics. The information in this study and similar ones to follow may provide valuable food for thought for breeders.— Karen Moriello, DVM, Diplomate ACVD

Mortality in North American dogs from 1984 to 2004: An investigation into age-, size-, and breed-related causes of death. Fleming JM, Creevy KE, Promislow DEL. J VET INTERN MED 25:187-198, 2011.