title: Average heart rates of hispanic and caucasian adolescents during sleep: longitudinal analysis from the TuCASA cohort.
abstract: OBJECTIVE
  The current study describes sleeping heart rate patterns in an adolescent cohort of Hispanic and Caucasian children over approximately a 5-year period to determine how sex, ethnicity, and body mass index (BMI) contribute to sleeping heart rate patterns over time.
  
  
  METHODS
  Participants were recruited from a large urban school district in the southwest United States as part of the Tucson Children's Assessment of Sleep Apnea Study (TuCASA). Heart rate data was obtained through electrocardiogram (ECG) recordings during in-home polysomnography, approximately 5 years apart. Second-wave cohort data were analyzed to determine how age, sex, ethnicity, physical activity, and BMI contribute to average sleeping heart rates. The same variables were used to investigate how sleeping heart rate patterns change longitudinally from school-age (6-11 years) to adolescence (10-17 years) during sleep.
  
  
  RESULTS
  Female adolescents had significantly faster average heart rates during sleep. Sleeping heart rate decreased significantly with increasing age in the adolescent cohort. Although the Hispanic group had a statistically significant higher body mass index than Caucasians, there were no significant differences in heart rate observed between ethnicities or in those who were classified as obese (BMI ≥ 95(th) percentile for age). Longitudinal analysis between the school-aged and adolescent cohort revealed a significant overall decrease in heart rate across a 5-year period.
  
  
  CONCLUSIONS
  Hispanic and Caucasian adolescents experience a similar decrease in sleeping heart rate with age. Female adolescents had significantly faster heart rates than males, and no significant differences were observed between Caucasians and Hispanics, or obese vs. nonobese adolescents.
authors.forename: Kristen
authors.initials: K
authors.lastname: Hedger-Archbold
authors.forename: Seth T
authors.initials: ST
authors.lastname: Sorensen
authors.forename: James L
authors.initials: JL
authors.lastname: Goodwin
authors.forename: Stuart F
authors.initials: SF
authors.lastname: Quan
mesh_terms: D000293:Adolescent; D001130:Arizona; D015992:Body Mass Index; D002648:Child; D015331:Cohort Studies; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006630:Hispanic or Latino / Q000706:statistics & numerical data*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D017286:Polysomnography; D012737:Sex Factors; D012890:Sleep / Q000502:physiology*; D011795:Surveys and Questionnaires; D044465:White People / Q000706:statistics & numerical data*
keywords: adolescents; heart rate; polysomnography