A recent study analyzes the correlation between behavioral problem and pain in order to increase awareness by veterinarians, behaviorists, and owners.
Published on 9 September 2022, by Simona Purrello
A recent study analyzed the relationship between pain and behavior in order to increase veterinarians’ and pet owners’ awareness of this important correlation.
The potential role of pain in behavioral problems (e.g., aggressive behavior, sensitivity to noise, etc.) is widely recognized, but available evidence is still scarce.
The prevalence of cases in which pain is the cause of a behavioral problem would seem to vary widely, from 28 to 82 percent of cases, and many of these conditions can be suspected through careful observation of the animal.
The presence of clinical abnormalities, such as an unusual gait or unexplained behavioral signs, should therefore not be ignored, even in cases where such abnormalities are common in a given breed.
Increased awareness of veterinarians
A recent study published in Animals attempted to illustrate the scope and nature of the problem in order to raise awareness on the part of veterinarians, behaviorists and owners.
The authors suggest that the relationship between behavioral problem and pain can be categorized into four patterns:
- The behavior presented by the animal is a direct manifestation of pain;
- unidentified pain underlies secondary manifestations within the initial behavioral problem;
- there is an exacerbation of one or more signs of behavioral problems caused by pain;
- additional behavioral problems are associated with pain.
Let us briefly go through each of the categories, but refer to the original article for the descriptive cases that the authors propose for each model.
Behavior, direct manifestation of pain
Within this category is a range of behavioral problems, but perhaps the most widely recognized are forms of aggressive behavior, as agonistic behavior serves to avoid contact with humans or other animals. Typically, these animals are often described as having a mild but changeable temperament, a “Jekyll and Hyde” type of personality. This category also includes animals whose pain affects their learning and performance. For example, not learning to sit properly may be due to pain associated with the placement of the dysplastic hips in that position, and this can occur even in puppies.
Pain-related performance problems may also occur only during specific movements (e.g., unilateral difficulty where a localized source of pain is present) or may have a more general effect on performance (e.g., slowness or reluctance).
Finally, chronic arthritic pain, especially in older or overweight animals, has been hypothesized to be the cause of reluctance in cats to access the litter box. These cases can respond with appropriate analgesia. Similar movement aversion has also been reported in older dogs with chronic musculoskeletal pain.
Unidentified pain underlying secondary manifestations
In some cases, a primary disorder may be behavioral, but one or more signs of the same disorder may be related to pain.
This is perhaps a less recognized but no less important situation, as failure to recognize the problem can lead to a failure to recognize the aspects associated with the pain.
These cases not are well documented in the literature, but the authors present a couple of illustrative case studies, including one showing how a painful hip injury can cause a relapse into a past behavioral problem of the animal-in this case aggression toward other known animals-that is instead due precisely to the new pain.
Exacerbation of behavioral problems
Sometimes pain is not the cause of the behavioral problem, but it can exacerbate negative affective states, such as anxieties, fears, and frustrations.
However, this relationship is probably bidirectional, in fact it would seem that animals suffering from relationship problems are also potentially more sensitive to pain.
As mentioned above, if we operate according to the precautionary principle, whenever there is suspicion of pain involvement in a behavioral case, treatment should consider from the outset the management of both pain and negative affective states. This is true even if there are no overtly painful injuries.
Additional behavioral problems are associated with pain
Most veterinarians are familiar with various signs of pain:
- An abnormal gait or posture;
- the sudden “freezing.”
- Unusual/exciting defecation and urination behavior;
- The act of biting or scratching a specific area, especially if sudden and accompanied by wincing.
In the clinic, restlessness, including excessive sniffing, as well as signs of anxiety and seeking the owner’s attention may also be indicative of chronic pain.
Recently, some Authors reported that more than three-quarters of pugs with an abnormal sitting posture (a leg tucked under the body, sometimes referred to as “lazy sitting”) also had an abnormal gait.
These dogs were not only more likely to be irritable, reluctant to take a walk and unable to jump, but they also had a much higher prevalence of additional behavioral disorders that might be less widely associated with pain. These included abnormal scratching of the head and neck, air licking, as well as fly popping syndrome.
Conclusions
So, where the presence or involvement of pain in animal reported for a behavioral problem is suspected, it is important to keep an open mind about the potential influence that pain itself might have on that individual even if the link should appear unlikely or undocumented in the published literature.
Reference
Mills DS, Demontigny-Bédard I, Gruen M, et al. Pain and Problem Behavior in Cats and Dogs. Animals (Basel). 2020;10(2):318. Published 2020 Feb 18. doi:10.3390/ani10020318
