Extremely high or low resting heart rates in young men may predict psychiatric illness later in life, a large new study has found.

Researchers used heart rate and blood pressure data gathered at Swedish military inductions from 1969 to 2010, and linked them with information from the country’s detailed health records through the end of 2013. The study, in JAMA Psychiatry, included 1,794,361 men whose average age was 18 at induction.

The highest heart rates — above 82 beats a minute — were associated with increased risks of obsessive-compulsive disorder, anxiety disorder and schizophrenia. The lowest, below 62 beats, were associated with an increased risk of substance abuse and violent criminality. Extremes in blood pressure followed similar patterns, but the associations were not as strong.

The lead author, Antti Latvala, a researcher at the University of Helsinki, said that the reasons for the association remain unknown. But, he added, “These measures are indicators of slightly different reactivity to stimuli. These people might have elevated heart rates because of an elevated stress level that is then predictive of these disorders.”