Study links heart rate variability to anxiety-related behavior problems in dogs

Research has found a physiological difference between dogs affected and unaffected with anxiety problems.

The study found that heart rate variability — meaning the variation in the time interval between heartbeats — was related to a range of anxiety-related behavior problems in dogs. The study was published in the journal Physiology & Behavior.

PsyPost interviewed Dennis Wormald of the University of Melbourne about his study. Read his responses below:

PsyPost: Why were you interested in this topic?

Wormald: While there are a large number of behaviour problems in dogs that are all believed to be “anxiety-related”, there are few objective measures that can be used to indicate risk of having these problems. In human psychiatry there are a range of validated questionnaires or scales that can be used to diagnose behaviour disorders. However, in dogs this diagnosis depends greatly on the history that the owner can supply. Therefore I was interested in trying to identify possible physiological biomarkers for the whole range of anxiety-related behaviour problems in dogs (assuming they are related somehow). Heart rate variability (HRV) was known to be related to some mental disorders in humans, and so we explored the link in dogs.

What should the average person take away from your study?

This study has found the first evidence of differences heart rate variability between dogs that are either affected or unaffected by anxiety-related behaviour problems (such as aggression, noise phobia, separation anxiety). This could have future applications in understanding or identifying these behavioural disorders. HRV is linked to the way in which humans respond to emotional stimuli, we believe that this also occurs in dogs and is the explanation in of our findings. Dogs that have anxiety-related behaviour problems tend to have reduced HRV indicating a possible deficiency in dealing with stress or anxiety.

Are there any major caveats? What questions still need to be addressed?

This study looked only at dogs that had 2 or more anxiety-related behaviour problems, compared to dogs that had none. It is possible that some dogs with an individual anxiety-related behaviour problem would not have this link. The exploration of this link with individual diagnoses (such as fear-aggression) still needs to be performed. We also do not know if this is a cause or effect, it would be great to measure HRV in a cohort of puppies and see if it predicts which ones go on to develop problems.

Is there anything else you would like to add?

For those who don’t know, HRV is a measure of how much the heart beat varies in its rhythm, with a very steady beat indicating low HRV. The difference in HRV between individuals is partly due to the way in which the brain controls the heart beat through the parasympathetic and sympathetic nervous system. Studies in humans have correlated low HRV with a range of problems including some psychological disorders and risk of death due to heart disease. The precise reason for this link is not known despite many studies attempting to address the subject.

The study, “Reduced heart rate variability in pet dogs affected by anxiety-related behaviour problems“, was also co-authored by Andrew J. Lawrence, Gabrielle Carter and Andrew D Fisher.