title: Differences in heart rate variability between Asian and Caucasian children living in the same Canadian community.
abstract: Heart rate variability (HRV) is an umbrella term for a variety of measures that assess autonomic influence on the heart. Reduced beat-to-beat variability is found in individuals with a variety of cardiac abnormalities. A reduced HRV positively correlates with obesity, poor aerobic fitness, and increasing age. Racial (black-white) differences are apparent in adults and adolescents. We aimed to evaluate (i) Asian-Caucasian differences in HRV and (ii) differences in HRV between girls and boys. Sixty-two children (30 male (15 Caucasian, 15 Asian) and 32 female (15 Caucasian, 17 Asians)) with a mean age of 10.3 +/- 0.6 y underwent 5 min resting HRV recording, fitness testing (Leger's 20 m shuttle), and self-assessed maturity. Outcome HRV measures were a ratio of low to high frequency power (LF:HF), standard deviation of R-R intervals (SDRR) and root mean square of successive R-R intervals (RMSSD). Data were compared between groups using analysis of covariance (ANCOVA). There were no race or sex differences for time domain variables, mean R-R, body mass index, or blood pressure. Compared with Caucasian children, Asian children displayed a higher adjusted (fitness, R-R interval) LF:HF ratio (72.9 +/- 59.4 vs. 120.6 +/- 85.3, p < 0.05). Girls demonstrated a higher adjusted LF:HF power than boys (117.2 +/- 85.1 vs. 76.6 +/- 62.4, p = < 0.05). In conclusion, Asian and Caucasian children display different frequency domain components of heart rate variability.
authors.affiliation: School of Human Kinetics, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Katharine E
authors.initials: KE
authors.lastname: Reed
authors.forename: Darren E R
authors.initials: DE
authors.lastname: Warburton
authors.forename: Crystal L
authors.initials: CL
authors.lastname: Whitney
authors.forename: Heather A
authors.initials: HA
authors.lastname: McKay
mesh_terms: D044466:Asian People; D002170:Canada; D002648:Child; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D012727:Sex Characteristics; D044465:White People