Low resting heart rate in men tied to increased violent criminality
Key Takeaways
Young men with a low resting heart rate have a significantly increased risk to be convicted of a violent crime in later adulthood, according to a study of more than 700,000 men.
This study found that men with the lowest heart rate (≤60 beats per minute) had a 39% higher risk of being convicted of violent crimes compared with men with the highest resting heart rate (≥83 beats per minute), according to a study published online September 9, 2015 in JAMA Psychiatry.
Men with the lowest resting heart rate also had a 25% higher risk of being convicted of nonviolent crimes, including drug-related crimes, property crimes, and traffic crimes.
In children and adolescents, low resting heart rate has long been associated with aggressive and antisocial behavior. But no large population studies have determined whether low resting heart rate increases the risk of violence and other antisocial and risk-taking behaviors in adults.
This study used data on 710,264 Swedish men, born between 1958 and 1991, whose resting heart rate and blood pressure were measured at mandatory military conscription testing when the men were an average age of 18 years old. With up to 35.7 years of follow-up, the researchers were able to trace the military data to criminal records, and determined that 40,093 of the men were convicted of a violent crime.
“When we further adjusted for cardiovascular fitness, the associations [of low resting heart rate and violent criminality] were even stronger,” said lead investigator Antti Latvala, PhD, of the University of Helsinki, Finland.
“Among men who were convicted of violent crimes, lower resting heart rate predicted earlier age of first conviction,” he added.
In addition to the crime outcomes, men with low resting heart rate are also more likely to be injured as a result of violence and more likely to be unintentionally injured, as in traffic accidents.
Similar to resting heart rate, low systolic blood pressure also showed associations with violent and nonviolent criminality and assault injuries.
The authors stop short of concluding that low resting heart rate causes violent and antisocial behavior. Rather, they speculate that low resting heart rate could be an indicator of a chronically low level of psychological arousal, which may lead some people to seek stimulating experiences. Or, low resting heart rate could be a marker of weakened responses to aversive and stressful stimuli, which can lead to fearless behavior and risk taking.
“Our results confirmed the association between low resting heart rate and subsequent antisocial behavior across adulthood,” Dr. Latvala said. “Now we know that this is a real association, it will be possible to design different experimental or quasi-experimental studies where we can try to test different hypotheses.”
Could this association have a practical applications for law enforcement or prophylactic treatment of these individuals? “Physiological markers such as heart rate might be useful, in combination with other well known risk factors, for identifying individuals who have an elevated risk for antisocial behavior and violence,” he said. “But it is uncertain whether the association with heart rate—although it’s a real phenomenon—is strong and specific enough for this task.”