Changes in autonomic regulation with age: Implications for psychopharmacologic treatments in children and adolescents

Developmental changes in the cardiovascular system could have an impact on risks associated with psychopharmacological interventions. Children may be more vulnerable to adverse cardiac events due to immaturity in autonomic co ntrol of the heart. These changes are incompletely understood and are chara cterized in this study. A consecutive series of 70 boys, aged 6-14 years, w as recruited. Developmental variation in the autonomic nervous system was e valuated by assessing heart period variability (HPV), pulse, and blood pres sure in response to orthostasis. Increased age correlated significantly wit h greater heart rate and diastolic blood pressure response to orthostasis. HPV at rest and in response to tilt did not significantly correlate with ag e. Boys with family histories of hypertension had a significantly greater b lood pressure response to orthostasis. These findings suggest that developm ental age-related changes in the sympathetic nervous system, as reflected b y changes of pulse and blood pressure response to tilt, occur across this a ge range. Parasympathetic changes, as reflected by HPV, do not. In light of these findings, more research is needed on children's and adolescents' rel ative cardiac risk with psychotropic medications as opposed to adults'.