Incidence of Diabetes Mellitus in Insured Swedish Cats in Relation to Age, Breed and Sex

Abstract

BackgroundDiabetes mellitus (DM) is a common endocrinopathy in cats. Most affected cats suffer from a type of diabetes similar to type 2 diabetes in humans. An increasing prevalence has been described in cats, as in humans, related to obesity and other lifestyle factors.ObjectivesTo describe the incidence of DM in insured Swedish cats and the association of DM with demographic risk factors, such as age, breed and sex.AnimalsA cohort of 504,688 individual cats accounting for 1,229,699 cat‐years at risk (CYAR) insured by a Swedish insurance company from 2009 to 2013.MethodsWe used reimbursed insurance claims for the diagnosis of DM. Overall incidence rates and incidence rates stratified on year, age, breed, and sex were estimated.ResultsThe overall incidence rate of DM in the cohort was 11.6 cases (95% confidence interval [CI], 11.0–12.2) per 10,000 CYAR. Male cats had twice as high incidence rate (15.4; 95% CI, 14.4–16.4) as females (7.6; 95% CI, 6.9–8.3). Domestic cats were at higher risk compared to purebred cats. A significant association with breed was seen, with the Burmese, Russian Blue, Norwegian Forest cat, and Abyssinian breeds at a higher risk compared to other cats. No sex predisposition was found among Burmese cats. Several breeds with a lower risk of DM were identified.Conclusions and clinical importanceOur results verify that the Burmese breed is at increased risk of developing DM. We also identified several previously unreported breeds with increased or decreased risk of DM.

Environmental Risk Factors for Diabetes Mellitus in Cats

“…Similarities between type 2 diabetes in cats and people include common risk factors, such as obesity, age, and physical inactivity, as well as similar pathophysiological findings, including deposition of amyloid in islets . Other risk factors associated with increased risk of DM in cats include male sex, neutering, indoor confinement, and treatment with certain drugs …”

“…Diabetes mellitus (DM) in cats has an incidence of 11.6 cases per 10,000 cat‐years at risk . Most cats suffer from a type of DM similar to type 2 diabetes (T2DM) in people, characterized by a relative deficiency of insulin secretion combined with insulin resistance, in contrast to the primary beta‐cell deficiency of type 1 diabetes.…”

“…The main aim of this study was to investigate the associations between DM in cats and environmental risk factors. We have previously reported on demographic risk factors for DM in Swedish cats, using data from the same insurance register …”

Epidemiology of Diabetes Mellitus among 193,435 Cats Attending Primary‐Care Veterinary Practices in England

“…A genetic component for DM in cats is also indicated by specific feline breeds appearing to be at increased or decreased risk of DM. Several studies have identified an increased risk of DM in Burmese cats in the United Kingdom, Europe, and Australia, and a recent Swedish investigation demonstrated an increased risk in Norwegian Forest cats, Russian Blues and Abyssinians, and a decreased risk in Persians . An increased risk for DM has not been documented in American Burmese cats, which has been attributed to American Burmese being genetically distinct from Burmese in other parts of the world …”

“…Several studies have identified an increased risk of DM in Burmese cats in the United Kingdom, Europe, and Australia, and a recent Swedish investigation demonstrated an increased risk in Norwegian Forest cats, Russian Blues and Abyssinians, and a decreased risk in Persians. 2,17,18 An increased risk for DM has not been documented in American Burmese cats, which has been attributed to American Burmese being genetically distinct from Burmese in other parts of the world. 19 The only previous study to investigate risk factors for DM in cats in England analysed a modest-sized insured population of 14,030 cats.…”