Researchers have found that a low resting heart rate may be linked to criminal convictions, as well as medical treatments and death from assaults and unintentional injuries.
For the study, researchers led by Antti Latvala from the University of Helsinki examined data from 710, 264 men from Swedish national registers born between 1958 and 1991. With a follow up of up to 35.7 years, the researchers used data on each participant's resting heart rate and blood pressure taken from medical assessment prior mandatory military conscription. They then compared these results to their criminal records and health data indicative of involvement in violent activity.
In the end, the researchers found that low resting heart rates among men during late adolescence were linked to an increased risk of criminality, assault and accidental injury later on in life. These findings echo those from earlier studies with smaller sample sizes.
"The finding is not a chance finding," says Dr. Adrian Raine, professor of criminology, psychiatry and psychology at the University of Pennsylvania. "I found this in my PhD thesis back in 1981...School kids who were antisocial and aggressive had lower resting heart rates. There are many other studies showing the same thing, and the finding by Latvala et al replicates in more than 12 different countries.”
“Their study, however, is by far and away the biggest study ever conducted, and as you see, it is showing that all types of criminal offending, violent offending, drug offending, property offending, even traffic offending are linked to low heart rate.”
How exactly this happens is not yet completely understood. Dr. Raine said however that how one responds to fear may be responsible. Those who are less fearful are likely less stressed by life in general and thus have a lower heart rate. This lack of fear may then encourage individuals to do certain things normally considered taboo- such as criminality.
According to Kevin Dutton, author of ‘The Wisdom of Psychopaths’, criminality may not be the only thing those with this characteristic are more likely to undertake. He claims that lower, and better regulated heart rates are also a common characteristic of successful businessmen, monks and military bomb-disposal experts.