Behavioral signs of feline pain

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Cats are exceptionally adept at hiding signs of pain, but there are some behaviors pet owners and veterinarians should be aware of. Pet owners want many things for their pets, but a pain-free life is one of the key things they look for. Veterinarians are often asked if a cat is in pain, but it can be difficult to determine in the brief interaction in the exam room, especially for stoic or highly stressed cats. In many cases, veterinarians must rely on the owner’s observations of their pet’s behavior to detect those experiencing pain.

While pet owners may observe changes in their cat’s behavior that are indicative of pain, many believe these changes to be part of the aging process. This misconception may keep pet owners from mentioning their observations during routine preventative care visits. By educating owners on behavioral signs of pain and asking specific behavior-related questions during the examination, veterinarians can help to identify cats who may be subtly suffering from pain.

Degenerative joint disease: An underdiagnosed source of pain

A common under-recognized cause of pain in cats is degenerative joint disease (DJD). Radiographic studies of cats have found evidence of DJD in 61-92% of cats, with the incidence increasing with age.^1,3 While not all cats experience pain on examination of affected joints, approximately 40% of cats with radiographic signs of DJD do exhibit clinical signs of pain.⁴ Thus, the contribution of this disease to chronic pain should not be overlooked.

Pet owner observations are a crucial part of the work-up and can prompt veterinarians to assess patients more thoroughly for sources of pain. Numerous studies have investigated behavioral signs of pain in cats in an effort to develop clinical instruments and questionnaires that can be given to cat owners as screening tools, especially in cases of suspected DJD.^4-8

Mobility

Mobility changes are a reliable sign of pain in cats, but the observed changes are often more subtle than those that owners associate with pain in dogs. Since feline osteoarthritis is often a bilateral disease, lameness is less commonly noted.^4,9 General mobility changes that can be indicative of pain, include a stiff gait, changes in jumping distance or height, reluctance to go up or downstairs, limited stretching, and changes to scratching.

Asking specific questions about changes in a cat’s behavior and mobility at home can raise the index of suspicion for pain. Cats often like to sleep or spend time in elevated locations, such as cat trees, windowsills, and furniture. If jumping vertically becomes painful, they may elect to spend more time in locations that are easier to access. Asking clients where their cat likes to spend time and if they have noticed a change in preferred location can be a helpful way to assess this behavior.

In some cases, cats may not stop jumping altogether, but they may change the way they jump or access vertical surfaces. Cats who previously jumped several feet in the air or between objects may now make several smaller jumps to cover the same distance or less reliably hit their target. Consider asking owners how many jumps it takes for their cat to reach their favorite perch or how often their cat hits their intended target on the first try to assess these changes.

Changes in litterbox usage

One behavior change that is easily noticed by cat owners is inappropriate elimination. There are many medical and behavioral causes for this, including pain and bladder inflammation. Orthopedic pain should also be a consideration, especially in older cats. Often, the changes in elimination behavior that are indicative of orthopedic pain are because of difficulty accessing the litterbox or due to the location or size and shape of the box. Cats may also change their posture during urination and defecation from joint pain, but pet owners who do not see the act of elimination may not observe this.

In many homes, litter boxes are tucked away in laundry rooms, basements, or bathrooms. Cats may be required to use stairs to access the litterbox, but pain from undiagnosed joint disease could impact their willingness and ability to go up and down the stairs. In cases where a cat is unable to access their litter box, they may resort to urinating and defecating in areas of the house away from the box. Additionally, litter boxes that have high sides may become painful for a cat to access, resulting in inappropriate elimination near the box.

Asking pet owners who have observed inappropriate elimination specific questions about location of and access to litterboxes as well as the shape of the litterbox can help to determine if mobility changes may be contributing to the unwanted behavior. Suggesting relocating litter boxes or purchasing boxes with shorter sides to allow easier access may help to resolve this behavior in addition to treating pain.

Grooming

Cats are known to be fastidious groomers, but pain can interfere with normal grooming habits, causing both decreased or increased grooming. Cats who are uncomfortable turning themselves to reach their stomach, limbs, back or tail may exhibit decreased grooming behavior. This is often observed when the coat becomes matted or dirty. Other reasons for decreased grooming, such as obesity preventing the cat from reaching some areas of their body, should be considered as well. Alternatively, some cats will excessively groom painful areas leading to barbered hair, hair loss, and skin irritation. A thorough pain assessment should be included in the examination of any cat displaying excessive grooming behavior in the absence of obvious dermatologic disease or ectoparasites.

Socialization

Cats in pain may alter the amount of time they spend with their owners and other pets. Previously sociable, playful cats may become withdrawn and spend more time isolated or hiding from their family. Cats may resent being touched or pet in painful areas, resulting in hissing, growling, swatting, and biting. These particular behavioral changes can be especially distressing for owners as they negatively impact the human-animal bond between cat and owner.

Generalized behavior changes

Additional behavior changes that can indicate pain are more non-specific and should prompt a full work-up to assess for other medical causes of the changes. In the absence of metabolic disease or neoplasia, pain should be considered as causes of decreased appetite, decreased activity, increased vocalization, and increased restlessness or interrupted sleeping.

The take-home and useful resources

Educating pet owners on behavioral changes that may indicate pain is an important part of the veterinary team’s job in advocating for their feline patients. Educational tools are available from organizations such as the International Veterinary Academy of Pain Management (IVAPM). Veterinarians should also discuss ways to help cats with their mobility before they are showing overt signs of pain. Recommending joint supplements to senior and geriatric cats is a great way to do this.

Ultimately, even if owners are unaware of the importance of certain behavioral changes in their cats, veterinarians who ask the right questions can identify cats in pain. Screening tools for pain from DJD in dogs are readily available, but have been lacking for cats. A six-question screening checklist for cats was published in the Journal of Feline Medicine and Surgery in 2020.⁴ Longer, validated questionnaires, such as the Feline Musculoskeletal Pain Index (FMPI) can also be given to pet owners prior to the appointment or upon their arrival at the clinic. By helping pet owners to recognize the behaviors that indicate pain, veterinary teams can better recognize and treat cats suffering from chronic pain conditions.

Kate Boatright, VMD, is a 2013 graduate of the University of Pennsylvania, is a practicing veterinarian and freelance speaker and author in western Pennsylvania. She is passionate about mentorship, education, and addressing common sources of stress for veterinary teams and recent graduates. Outside of clinical practice, Dr Boatright is actively involved in organized veterinary medicine at the local, state, and national levels.

References

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