Published online by Cambridge University Press: 31 October 2018
A low resting heart rate across development from infancy to young adulthood relates to greater aggression/hostility. Adult aggression and a high heart rate relate to health risk. Do some aggressive individuals retain low heart rate and less health risk across development while others show high heart rate and more risk? A longitudinal sample of 203 men assessed as teens (age 16.1) and adults (mean age 32.0) permitted us to assess (a) stability of heart rate levels and reactivity, (b) stability of aggression/hostility, and (c) whether change or stability related to health risk. Adults were assessed with Buss–Perry measures of aggression/hostility; teens with the Zuckerman aggression/hostility measure. Mean resting heart rate, heart rate reactivity to speech preparation, and aggression/hostility were moderately stable across development. Within age periods, mean heart rate level, but not reactivity, was negatively related to hostility/aggression. Maintaining low heart rate into adulthood was related to better health among aggressive individuals relative to those with increasing heart rate into adulthood. Analyses controlled for weight gain, socioeconomic status, race, health habits, and medication. Low heart rate as a characteristic of hostile/aggressive individuals may continue to relate to better health indices in adulthood, despite possible reversal of this relationship with aging.