Burmese and Birman cats have the longest life expectancy of purebred cat according to a recently published study conducted between 2019 and 2021 in the UK. The researchers don’t tell us specifically or in detail why they have the longest life expectancy of the purebred cats and even to the extent where their lifespan is longer than for random-bred cats (moggies).
However, my research tells me that hypertrophic cardiomyopathy (HCM) is less prevalent in Burmese and Birman cats than it typically is in other purebred cats. And where it is particularly prevalent such as in Sphynx cats (about 34%), Bengal cats and Maine Coons for example, it substantially shortens their lives with the Sphyx having the shortest lifespan of all the breeds.
So, I’m going to conclude that the reason why the Birman in Burmese lead the way in this study on domestic cat lifespans is because they don’t suffer as much as other cat breeds in respect of developing HCM which can start as youngest four or five months of age. Although both these breeds have their own genetic diseases: Birman Health Problems.
The crossbreed or moggy cat does not inherit HCM to the extent of the purebred cats but it must happen from time to time. The reason why crossbreed or random-bred cats have ostensibly shorter lifespans than the Burmese and Birman is probably because they are indoor/outdoor cats which makes them vulnerable them to injury and fatal accidents compared to the purebred cats which are far more often full-time indoor cats where they are much safer. There is this distinct background difference when comparing crossbreed and purebred cats.
RELATED: Cat breeds prone to HCM
Overall, hypertrophic cardiomyopathy is a common heart disease in all domestic cats but far more so in the purebreds because they are selectively bred i.e. inbred companion animals which means that if this genetically inherited disease enters the bloodlines it stays within them. The only way to minimise the disease in a bloodline is to crossbreed or outcross with probably random-bred domestic cats or a breed that is known to be almost free of HCM. Breeders don’t want to do that because it would seriously undermine the appearance of their cats which have been refined over many years to match up to the breed standard.
That’s why HCM sticks around in these breeds. It never goes away and it shortens the life spans of many thousands of cats. And, it has to be added this disease presents a very bad public image for the cat fancy. It worries the public. For example, if you’ve enjoyed the pleasure of a Sphynx cat in the past and have seen your beloved companion animal die very young at about seven years of age or less (the average lifespan of Sphynx cats is 6.7 years) you are unlikely to want to adopt another Sphynx cat.
Perhaps it might be reasonable to suggest that those people who adopt i.e. purchase a Sphynx cat from a breeder do so without knowledge of the potentially devastating effect of HCM on their chosen animal’s lifespan. Sphynx cat health concerns.
Excess weight
Although I believe that HCM is the primary factor in reducing lifespan of these cat breeds, a secondary factor would be obesity. The study also concluded that for every extra hundred grams of bodyweight that a cat carried, they reduced their lifespan by about 2.5 months. This then is about obesity which can lead to feline diabetes and feline diabetes can ultimately kill domestic cats. It’s a serious illness as it is for humans. And of course obesity in general affects health which can lead to a shortened lifespan.
You can read more about this in a recent article. And this may interest you: Infographic on 5 thoughts on excess weight in cats
Maintenance
Regular checkups are probably advisable for purebred cats like the Sphynx because early detection and diagnosis can positively impact a cat’s life expectancy. And cats with HCM might benefit from a specialised diet and medication to manage symptoms and improve overall health.
RELATED: Hypertrophic cardiomyopathy (HCM) affects 10% of British Shorthairs
So, these purebred cats predisposed HCM are going to need veterinary monitoring ideally and we know that in the UK veterinarians have put up their prices to a level which for some is unmanageable. This puts cat owners in an invidious position. They might have to take out pet health insurance which can be expensive and it is an added financial burden to cat caregiving which at the moment is unwelcome because the cost of living in the UK is considered high.
And in general, people don’t really want to take out pet health insurance unless they have to because it is an added overhead for the family.
Despite HCM’s impact on lifespans, sometimes cats with this disease may live as long as 12 years but others might only survive for a few months or years. The outcome is variable.
My research indicates that the prevalence of HCM in Birman cats is about 7% of screened cats. As you can see that’s much lower than 34% for sphynx cats. That’s why Birmans live the longest and sphynx cats live the shortest lives.
HCM can affect Burmese cats but my argument would be that it is less prevalent in that cat breed than in breeds with shorter life spans. This is not to say that Burmese cats don’t have inherited diseases; they do: Burmese Cat Health.
HCM
The completeness, HCM affects the anatomy of the cat’s heart by thickening up the ventricular wall. This affects heart function. Gene mutation troponin-T (TNNT2) implicated in HCM in Maine Coon cats
The classic symptoms will haps be those that one would expect such as lethargy i.e. low energy, breathlessness or sudden difficulty breathing, fainting or collapsing, a reduced appetite, a fast heart rate and a heart murmur. There might be paralysis of back legs due to the formation of blood clots that block blood flow to the hind legs causing paralysis and unfortunately some cats with HCM may die suddenly without warning.
RELATED: HCM in male and female Bengal cats and humans, a comparison
Note: Please forgive the occasional typo. I have to prepare these articles at breakneck speed. 😢💕🤔
The Times has picked up on the story
I am pleased to say that The Times my favourite newspaper has picked up on this story. It’s an important story because the longevity of purebred cats is probably the most important factor or should be in selecting a cat breed. The newspaper says that these results have been used to compile the first “life tables” for domestic cat companions in the UK. A database that will guide on life expectancy. It’s a database which will be used by veterinarians and cat caregivers to help decide whether treatments and/or surgical procedures are suitable and help identify those breeds with life-limiting genetic diseases.
The associate professor of companion animal epidemiology at the Royal Veterinary College and a co-author of the study, Dan O’Neill, said: “Since the early civilisation of man, predicting the future has been one of our greatest fascinations. These new life tables finally enable owners of cats to do just this, and to predict the future life expectancy for their cats based on novel scientific methods and the power of big data.”
