Retrospective epidemiological study of canine epilepsy in Japan using the International Veterinary Epilepsy Task Force classification 2015 (2003–2013): etiological distribution, risk factors, survival time, and lifespan

Abstract

BackgroundEpilepsy is the most common neurological disease in veterinary practice. However, contrary to human medicine, epilepsy classification in veterinary medicine had not been clearly defined until recently. A number of reports on canine epilepsy have been published, reflecting in part updated proposals from the human epilepsy organization, the International League Against Epilepsy. In 2015, the International Veterinary Epilepsy Task Force (IVETF) published a consensus report on the classification and definition of canine epilepsy. The purpose of this retrospective study was to investigate the etiological distribution, survival time of dogs with idiopathic epilepsy (IdE) and structural epilepsy (StE), and risk factors for survival time, according to the recently published IVETF classification. We investigated canine cases with epilepsy that were referred to our teaching hospital in Japan during the past 10 years, and which encompassed a different breed population from Western countries.ResultsA total of 358 dogs with epilepsy satisfied our etiological study criteria. Of these, 172 dogs (48 %) were classified as IdE and 76 dogs (21 %) as StE. Of these dogs, 100 dogs (consisting of 65 with IdE and 35 with StE) were included in our survival study. Median survival time from the initial epileptic seizure in dogs with IdE and StE was 10.4 and 4.5 years, respectively. Median lifespan of dogs with IdE and StE was 13.5 and 10.9 years, respectively. Multivariable analysis demonstrated that risk factors for survival time in IdE were high seizure frequency (≥0.3 seizures/month) and focal epileptic seizures.ConclusionsFocal epileptic seizures were identified as a risk factor for survival time in IdE. Clinicians should carefully differentiate seizure type as it is difficult to identify focal epileptic seizures. With good seizure control, dogs with IdE can survive for nearly the same lifespan as the general dog population. Our results using the IVETF classification are similar to previous studies, although some features were noted in our Japanese canine population (which was composed of mainly small-breed dogs), including a longer lifespan in dogs with epilepsy and a larger percentage of meningoencephalomyelitis of unknown origin in dogs with StE.

Intranasal Midazolam versus Rectal Diazepam for the Management of Canine Status Epilepticus: A Multicenter Randomized Parallel‐Group Clinical Trial

“…Status epilepticus can be caused by toxic and metabolic causes or structural brain disease. It can also occur as a manifestation of idiopathic epilepsy, with an estimated 20–60% of affected dogs experiencing at least 1 episode of status epilepticus during their lifetime …”

“…It can also occur as a manifestation of idiopathic epilepsy, 3 with an estimated 20-60% of affected dogs experiencing at least 1 episode of status epilepticus during their lifetime. 2,4 Status epilepticus is a life-threatening condition in dogs with an estimated case fatality rate of 25.3-38.5% 5,6 and requires immediate management in order to avoid primary and secondary permanent damage to the brain [7][8][9][10][11] or other severe systemic complications such as hyperthermia, acidosis, disseminated intravascular coagulation, and renal and cardiopulmonary failure. 12 2 Therefore, effective first-line management of emergency seizures both at home and in the hospital environment is vital and potentially life-saving.…”

Associations between neutering and idiopathic epilepsy in Labrador retrievers and Border collies under primary veterinary care in the UK

“…The published literature also offers limited information on associations between neutering and the clinical course of epilepsy in dogs. Sex and neuter status were not significant risk factors for survival in 172 referral cases in Japan (Hamamoto et al, 2016).…”

Postencephalitic epilepsy in dogs with meningoencephalitis of unknown origin: Clinical features, risk factors, and long‐term outcome

“…11,15,16 Furthermore, certain MRI features such as T2-weighted fluid attenuation inversion recovery (T2-FLAIR) abnormality of mesial temporal structures, cortical and subcortical involvement, as well as gadolinium contrast enhancement are predictive of PEE in patients with infectious and autoimmune encephalitis. 15,16 Although the presence of seizures in dogs with MUO has been associated with shorter survival times, [21][22][23][24] little is known regarding predictors of seizures and PEE. Therefore, the aims of this study were to report the clinical features, prevalence, risk factors, and long-term outcome of PEE in dogs with MUO.…”