Pressure vests are a controversial, under-studied but widely available form of complementary treatment said to ease the signs of anxiety and fear in dogs. Exactly why they are thought to have a calming effect on canines with issues ranging from separation anxiety to a fear of thunderstorms is unclear. Although a number of possible explanations have been mooted – acupressure points, or a sensation akin to swaddling a baby – the evidence supplied by manufacturers is largely anecdotal.
What does the veterinary evidence say?
Unfortunately, the bottom line to whether or not pressure vests actually work is as inconclusive as the attempts to explain why they might. In essence, according to current evidence, a pressure vest may calm down an anxiety-prone dog, or it may not.
However, despite that ambiguity, a number of insights useful to veterinary professionals and pet owners can be gleaned from the relevant research identified in the Knowledge Summary “Are pressure vests beneficial at reducing stress in anxious and fearful dogs?” published in Veterinary Evidence.
the bottom line to whether or not pressure vests actually work is as inconclusive as the attempts to explain why they might
Associative learning
In a similar fashion to Ivan Pavlov’s discovery that dogs begin to salivate upon hearing a sound they associate with the upcoming delivery of food, a trend in one of the studies suggests classical conditioning may also be involved in a dog’s positive response to wearing a pressure vest.
Applying a pressure vest to thunderstorm-wary dogs in between storms was intended to disassociate wearing one from the anxiety trigger. The dogs’ “anxiety scores” continually decreased the more times they wore the vest during a storm, indicating a process of associative learning may increase the likelihood of treatment with a pressure vest being successful.
The need for a dog to adapt to wearing a vest was exemplified by another study, which demonstrated an increase in heart rate upon application of the vest. Conversely, however, this also shows that use of a pressure vest – in the initial stages at least – may induce anxiety in individual dogs. Vets and owners should bear this in mind if they are considering recommending or using a vest.
Mixed messages
One of the major issues with most reports of a positive response is that they are subjective (often provided by owners). This makes the data difficult to rely upon – a problem enhanced by the lack of a standardised measure of anxiety in dogs.
Furthermore, possible collateral effects of wearing a pressure vest are not understood and may affect interpretation of the data. For example, dogs in the studies spent less time lying down or orientating towards a door when wearing a vest, but this doesn’t take into account that, for instance, it may be more uncomfortable for a dog to lie down when wearing a vest.
The objective measures of anxiety among the available evidence are equally confusing. On the one hand, dogs treated with a pressure vest showed a decrease in heart rate over time compared to their counterparts in either a loosely fitted vest (so as not to apply pressure) or not in one at all.
On the flipside, measures of urinary oxytocin and cortisol in saliva failed to demonstrate a significant effect of treatment with a pressure vest, despite the same research proving that cortisol levels increase in response to a noise stressor.
The take-home message, therefore, is that “pressure vests may have small but beneficial effects on canine anxiety… and using repeatedly may improve the likelihood of any benefit” but you should ensure the owner does not expect “their dog’s anxiety to be fully alleviated or prevented, and it may have no beneficial effect at all”.
