Overweight, Obesity, and Pain in Cats: Overview
Is being overweight and obese really a problem for cats? More than 50% of cats and dogs in North America are overweight or obese. These epidemic levels are reflected in the human population as well. Obesity in pets is now the most important disease process pet owners must face. And the effects of obesity are far reaching because it contributes to many other diseases and shortens cats’ lives.
What other medical conditions are associated with obesity?
For overweight and obese cats, one major concern is the dramatically increased risk of diabetes mellitus. In addition, obesity increases the risk for and consequences of heart disease and many types of cancer. Although we do not yet have a scientific study in cats, excess weight and obesity in dogs have been shown to shorten life expectancy by as much as two years. It is quite likely that we will find this frightening statistic to be true for cats as well.
"Obesity contributes to many other diseases and shortens cats’ lives."
Even more common than diabetes, excess weight and obesity set the stage for joint damage and osteoarthritis (OA), leading to chronic pain. One study showed that 90% of cats 10 years of age and older had X-rays that showed significant deterioration of multiple joints - in both the legs and spine. It takes years of joint damage for such changes to show up on an X-ray. That means cats that are overweight or obese are traumatizing their joints over a very long period before we can see clinical evidence of that damage.
Is there more to this linkage between obesity/being overweight and pain?
Until recently, veterinarians thought that the increased pain and inflammation associated with OA in overweight and obese cats was primarily due to the increased wear and tear on the joints. What we now know is that fat tissue is very biologically active and secretes hormones and other chemicals that both cause and enhance inflammation.
A hormone called leptin, is produced by fat cells and causes inflammation when it infiltrates joints. In addition, leptin may influence the bone changes associated with OA. Finally, inflammation can affect the body’s responses to other hormones such as cortisol and insulin, further unbalancing the body’s attempts at self-regulation and influencing the amount and extent of pain cats experience. The important underlying message is that fat itself contributes to inflammation, inflammation is a part of the pain associated with OA and degenerative joint disease, and being overweight or obese contributes to this vicious cycle. How can I tell if my cat is overweight or obese? The most reliable way to evaluate a cat’s body condition is with a hands-on examination. There are three key areas of the body to evaluate:
Just behind the shoulder blades, you should be able to feel individual ribs easily with the flats of your fingers.
At the end of the ribcage where the lower back begins, you should feel a clear indentation - similar to the shape of an hourglass - on your cat’s sides.
Although some cats have a fold of skin that 'droops' between the rear legs, the actual abdomen should feel 'tucked up'. If you were to draw a line along the abdomen from the end of the breastbone to the pelvis, the angle should be between 30 and 45 degrees.
If all of these criteria are met, odds are that your cat is in good body condition, which will contribute to a pain-free lifestyle. I’m not sure if my cat is overweight or obese. How can I be sure?
The best first step in the battle of the bulge is an evaluation by your cat’s veterinarian. Your cat’s weight and body condition score will be recorded in your cat’s medical record as a baseline (starting point). Be sure to ask that a pain assessment be included in the exam. If pain is present, the earlier it is detected, the quicker your cat can be treated and have her pain resolved. I know my cat is overweight. What can I do?
Your veterinarian is your best resource for feline weight loss. A specific food and portion per day will be recommended and you will be provided with guidance about how to deliver that portion based on lifestyle, convenience, and your cat’s individual needs. If there is already evidence of OA, reducing inflammation and pain will help encourage your cat to become more active, which will speed up appropriate weight loss. See handout “Overweight, Obesity, and Pain in Cats – Action Steps” for more ideas to help reduce your cat’s weight. What is my take-home message?
Fat cells contribute to inflammation. Inflammation causes pain. Therefore, having extra fat cells sets cats up to become and remain painful. The path to successful weight loss and weight maintenance includes partnership with your veterinarian to track results, as well as to manage any pain. Regular weigh-ins at your cat’s veterinary practice are important steps along the way.
"Having extra fat cells contributes to inflammation, which causes pain."
Once appropriate weight and body condition score are achieved, your veterinarian will recommend a maintenance food and daily portion. Ongoing regular assessments will help track the success of pain management strategies, and weigh-ins will provide accountability and ensure a great long-term outcome.
Contributors: Krista Williams, BSc, DVM; Robin Downing, DVM, CVPP, CCRP, DAAPM
Credit to: VCA Animal Hospital