Do Cats Have Seizures?
You might be thinking "Has she lost her mind? Of course cats have seizures!" Naturally, we know this to be true (or half of my research is for nothing...eek!) A recent article published in the Journal of Veterinary Internal Medicine looked at a population of cats in the UK in the year 2013 to answer some questions about feline epilepsy. I have bulleted them below for ease of reading however this is an open access article so feel free to pull the entire article if you would like to know more!
The study aims: "To estimate the prevalence of recurrent seizure disorders (RSD) and epilepsy in the wider cat population under primary veterinary care int he UK and to evaluate demographic risk factors for their occurrence. A secondary aim was to explore risk factors associated with the diagnosis of epilepsy among the subset of cats."
1-year prevalence (2013) for recurrent seizure disorders (not called epilepsy): 0.16%
1-year prevalence for epilepsy: 0.04%
* Note these are lower than the listed prevalence for referral institutions (and mobile veterinary neurologists) for the obvious reason that referral hospitals have a different caseload!
Diagnosing epilepsy in cats is not defined, as it is in dogs, by the International Veterinary Epilepsy Task Force (IVETF). Many neurologists, myself included, extrapolate from the IVETF recommendations but also realize the limitations in data for cats.
The IVETF recommendations for dogs to diagnose epilepsy (Tier 1 - aka without diagnostic testing) are:
two or more seizures, at least 24 hours apart
Age 6 months - 6 years old
Normal (unremarkable) neurologic examination inter-ictal
No clinical abnormalities on CBC, serum biochemisry, urinalysis
A diagnosis of epilepsy was made in this study in 24.89% of the cats with recurrent seizure disorders. There was a disturbing sentence that I quote "It is conceivable that general veterinary practitioners may feel reluctant to formally diagnose epilepsy or idiopathic epilepsy in cats because of a combination of factors, including their limited confidence in performing a complete neurological examination in cats, the longstanding traditional belief that cats do not commonly have idiopathic epilepsy, and a believe that access to advanced imaging is essential to exclude other causes." This sentence is the reason I chose this article for our TidBit Tuesday this week. First, if you're not diagnosing a cat with epilepsy (and presumable starting appropriate care or recommending appropriate testing) because of a lack of confidence in the exam, know that you are not alone! Please call me for a neurologic examination with your feline patient - I too understand the limitations of cats in assisting with their own health care. (To put it mildly.) Let's not let a lack of confidence in the examination block us from doing what is right by the pet. Secondly, idiopathic epilepsy does occur and in this study it was almost 1/4 of the cases of recurrent seizures (if they diagnosed it correctly, of course). It has been reported that up to 12% of cats can have a normal neurologic examination and have structural disease, but that shouldn't stop us from attempting appropriate treatment. Please, let's remove this thought from our practices. Finally, you do NOT need access to advanced imaging to make a presumptive diagnosis of idiopathic epilepsy. The Tier I recommendations were designed expressly to meet the needs of making this diagnosis (in dogs) without MRI or spinal tap. Whew...okay, back on track.
Following multivariate analysis, the only variable that stood out as a risk factor for a diagnosis of epilepsy was age. Cats 3-6 years of age had a 3.32 times higher odds of developing epilepsy then cats less than 3 years of age.
Insurance was also a risk factor but that doesn't apply to the majority of the pets that I interact with so I have left that portion of the study out. Breed and sex were not associated risk factors.
*O'Neill, DG, Phillipps, SA, Egan, JR, Brodbelt, D, Church, DB, Volk, HA. Epidemiology of recurrent seizure disorders and epilepsy in cats under primary veterinary care in the United Kingdom. J Vet Intern Med. 2020; 1– 13. https://doi.org/10.1111/jvim.15881
I hope you are doing well and staying safe. I appreciate what you do to help clients and their pets. Let me know how I can help you manage your patients with neurologic disease.
On site consultation is available Monday through Saturday at variable times throughout the week. Email consults are completed in evenings.
Have a good week!