| This study of canine hypoadrenocorticism determined incidence and prevalence, and identified factors associated with disease. Techniques used were historical; statistical, including meta-analysis and logistic regression; and epidemiologic. Existing data as well as data gathered by mail surveys of veterinarians were used. They proved useful. Point estimates of incidence and prevalence were 0.36/1000 dogs/yr and 1.8/1000 dogs, respectively. A point of estimate of average age at diagnosis was 4.9 yr, age was associated with the occurrence of disease, and the probability of disease increased with age. Female dogs were more likely to be hypoadrenal than males, and neutered dogs of either sex were more likely than intact ones. Breed was a significant factor in whether or not a dog developed hypoadrenocorticism. Airedale Terriers, Basset Hounds, Bearded Collies, German Shepherds, German Shorthaired Pointers, Great Danes, Poodles, Saint Bernards, Springer Spaniels, and West Highland White Terriers were at increased risk of disease. Boston Terriers, Boxers, Cocker Spaniels, Dalmatians, Lhasa Apsos, Pit Bull Terriers, Pomeranians, Shetland Sheepdogs, Shih Tzus, and Yorkshire Terriers were at decreased risk. A point estimate of average body weight of hypoadrenal dogs was 22.5 kg, body weight was associated with disease, and the probability of disease increased with body weight. Point estimates for serum sodium concentration, serum potassium concentration, and serum sodium to potassium concentration ratio of hypoadrenal dogs were 132.1 meq/L, 6.6 meq/L, and 21.1, respectively. Hypoadrenal dogs were seldom normal for all three diagnostic indicators. The study concluded that epidemiologic studies of canine hypoadrenocorticism may use the practicing veterinarian's diagnosis as a case definition rather than require a strict case definition based on the adrenocorticotropic hormone stimulation test. Logistic regression of data indicated that age, breed, sex, and body weight were associated with canine hypoadrenocorticism. |
