Great Pyrenees most commonly die from musculoskeletal diseases, cancer, and bloat. Their typical lifespan is 10 to 12 years, which is average for a giant breed. Because of their large frames and deep chests, they face a set of health risks that differ from smaller dogs, and understanding those risks can help you recognize problems early.
Musculoskeletal Disease Is the Leading Killer
A 20-year mortality study published in dvm360 found that musculoskeletal diseases were the top cause of death for Great Pyrenees, alongside other giant breeds like Saint Bernards, Great Danes, and Irish Wolfhounds. This category includes severe hip dysplasia, elbow dysplasia, degenerative joint disease, and the crippling pain and immobility that come with them.
The connection between joint disease and death isn’t always obvious. These conditions don’t kill directly the way cancer does. Instead, they progressively destroy a dog’s ability to walk, stand, and live without pain. In veterinary practice, mobility problems are the single biggest reason owners pursue euthanasia, with cancer as a close second. For a 100-plus-pound dog like a Great Pyrenees, the math is harsh: when the hind legs give out, there’s no easy way to carry or support them. A problem that might be manageable in a 30-pound dog becomes a quality-of-life crisis in a giant breed.
Hip dysplasia and elbow dysplasia are both recognized as significant enough in the breed that the Orthopedic Foundation for Animals includes screening for both in its recommended health testing program for Great Pyrenees. Patellar luxation, where the kneecap slips out of place, is also on the list. Responsible breeders screen parent dogs with radiographic evaluations before breeding, which reduces but doesn’t eliminate the risk in offspring.
Bloat: A Fast-Moving Emergency
Bloat, formally called gastric dilatation-volvulus (GDV), is one of the most dangerous conditions for any deep-chested breed, and the Great Pyrenees fits the profile perfectly. About 75% of bloat cases involve the stomach physically twisting inside the abdomen, which cuts off blood flow and traps gas. The remaining 25% involve the stomach filling with gas and expanding until it compresses surrounding organs. Either version can kill a dog within hours if not treated surgically.
The key risk factor is chest shape. Dogs whose chests are deep and narrow relative to their width have more room in the abdomen for the stomach to shift and rotate. Leaner dogs are also at higher risk than overweight dogs, likely because abdominal fat takes up space that would otherwise allow the stomach to move freely. Dogs that have bloated once tend to have a stretched ligament connecting the liver to the stomach, which may make recurrence more likely.
Signs of bloat include a visibly distended abdomen, unproductive retching (trying to vomit but nothing comes up), restlessness, drooling, and rapid breathing. This is a true emergency. Dogs that reach surgery quickly have a much better survival rate than those who wait even a few hours. Some owners of high-risk breeds opt for a preventive procedure called gastropexy, where the stomach is surgically tacked to the abdominal wall, often done at the same time as spaying or neutering.
Cancer
Cancer is a major cause of death across nearly all dog breeds, and giant breeds are no exception. While breed-specific cancer prevalence data for Great Pyrenees is limited compared to breeds like Golden Retrievers or Rottweilers, the cancers most associated with large and giant dogs include osteosarcoma (bone cancer) and hemangiosarcoma (a cancer of blood vessel walls that often affects the spleen or heart).
Osteosarcoma tends to strike the long bones of the legs, causing sudden lameness and pain. It’s aggressive, and by the time it’s diagnosed, it has often already spread. Hemangiosarcoma is equally devastating because it can grow undetected in internal organs until a tumor ruptures, causing sudden internal bleeding. Both cancers most commonly appear in dogs over age 7 or 8, which for a Great Pyrenees falls in the latter third of their expected lifespan.
Heart Disease and Other Genetic Risks
The OFA’s health testing recommendations for Great Pyrenees include a congenital cardiac exam, with an advanced cardiac evaluation recommended. Heart conditions in this breed can range from structural defects present at birth to conditions that develop over time. Cardiac disease doesn’t always show obvious symptoms early on, which is why screening matters for breeding dogs.
Degenerative myelopathy, a progressive spinal cord disease that causes gradual hind-leg paralysis, is another concern. A study of 85 Great Pyrenees found that about 8% carried two copies of the gene mutation associated with the disease, and another 12% carried one copy. While carrying the mutation doesn’t guarantee a dog will develop the condition, it means the genetic risk exists in the breed population. The disease typically appears in older dogs and progresses over months, eventually leaving the dog unable to walk.
Eye disease is also on the OFA screening list. While vision loss alone rarely causes death, it contributes to declining quality of life in senior dogs and can factor into end-of-life decisions when combined with other health problems.
What Aging Looks Like in Great Pyrenees
Great Pyrenees typically enter their senior years around age 7 or 8, and the signs of decline can be subtle at first. You might notice your dog struggling with stairs, being slower to stand after resting, or showing weakness in the back legs. These are common early signs of the joint and mobility problems that are so significant in the breed.
Weight changes in either direction deserve attention. Older dogs that become less active may gain weight, which puts additional strain on already-vulnerable joints. On the other hand, unexplained weight loss of more than 10% over a few months can signal cancer, kidney disease, or poor nutrient absorption. New lumps under the skin are common in aging dogs and are often harmless fatty growths, but any new lump should be evaluated to rule out something more serious.
Cognitive decline affects 14% to 35% of dogs over age 8. In Great Pyrenees, this can look like confusion, nighttime restlessness, forgetting familiar routines, increased anxiety, or house-training accidents. These changes can be distressing but are a normal part of canine aging, similar to dementia in humans. They become part of the larger picture when families are evaluating their dog’s overall quality of life alongside physical problems like pain, immobility, or organ disease.
Reducing Risk Through Screening
If you’re choosing a Great Pyrenees puppy, the single most impactful thing you can do is select a breeder who completes the full OFA-recommended health testing panel: hip and elbow radiographs, patellar luxation evaluation, eye exam by a veterinary ophthalmologist, cardiac exam, and ideally a DNA test for degenerative myelopathy. These tests don’t guarantee a healthy dog, but they significantly reduce the odds of inherited conditions that shorten lifespan.
For dogs already in your family, maintaining a healthy weight is one of the most effective ways to protect joints and reduce bloat risk simultaneously. Regular veterinary checkups become especially important after age 7, when the conditions most likely to affect this breed start showing up.