Background:We examined whether sympathetic nervous system activity influences hypertension status and systolic blood pressure (SBP) independent of adiposity in youth ranging from normal-weight to severe obesity.Methods:We examined the association of heart rate variability (HRV) with hypertension status and SBP among youth (6-18 y old; n = 188; 103 female). Seated SBP was measured using an automated cuff. Prehypertension (SBP percentile ≥ 90th to <95th) and hypertension (SBP percentile ≥ 95th) were defined by age-, sex-, and height-norms. Autonomic nervous system activity was measured using HRV via SphygmoCor MM3 system and analyzed for time-and frequency-domains. Total body fat was measured via dual-energy X-ray absorptiometry.Results:Logistic regression models demonstrated lower values in each time-domain HRV measure and larger low-frequency (LF):high-frequency (HF) ratio to be significantly associated with higher odds of being prehypertensive/hypertensive (11-47% higher odds) independent of total body fat (P < 0.05). In linear regression analysis, lower time-domain, but not frequency-domain, HRV measures were significantly associated with higher SBP independent of total body fat (P < 0.05).Conclusion:These data suggest that impaired cardiac autonomic nervous system function, at rest, is associated with higher odds of being prehypertensive/hypertensive and higher SBP which may be independent of adiposity in youth.
Bibliographical noteFunding Information:
The authors thank all of the children and adolescents who participated in this study. The authors also thank Annie Sheldon for her excellent coordination of this study, Cameron Naughton for program management, and Nicholas Evanoff for his technical expertise in measuring heart rate variability. No payment was received to produce this manuscript. All authors have seen, approved, and take full responsibility for the manuscript. J.R.R., D.R.D., K.D.R., and A.S.K. developed the aims and hypothesis. A.S.K. provided the funding. K.D.R. and M.O. performed the statistical analysis. J.R.R. wrote the first draft. M.O., T.A.B., L.C., K.D.R., D.R.D., C.K.F., J.S., and A.S.K. provided subject matter expertise and a critical review of the manuscript. Funding for this project was provided by funding from the National Institutes of Health (NIH; Bethesda, MD) the National Heart, Lung, and Blood Institute/NIH (R01HL110957, awarded to A.S.K.), the National Center for Advancing Translational Sciences/NIH (UL1TR000114), National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)/NIH NORC Grant Number P30 DK050456, and a training grant from the NIDDK/NIH (T32-DK083250 to J.R.R).
© 2016 International Pediatric Research Foundation, Inc.