Can we detect the development of baroreflex sensitivity in humans between 11 and 20 years of age?

• Published in: Canadian journal of physiology and pharmacology 2006-12, Vol.84 (12), p.1275-1283
• Main Authors: Zavodna, Eva, Honzikova, Natasa, Hrstkova, Hana, Novakova, Zuzana, Moudr, Jiri, Jira, Miroslav, Fiser, Bohumil
• Format: Article
• Language: English
• Subjects: Adolescent; adolescents; Adult; Age; Age Distribution; Age Factors; analyse spectrale; Anatomy & physiology; Baroreflex - physiology; baroreflex sensitivity; Biological and medical sciences; Blood Pressure; Case studies; Child; children; Children & youth; Czech Republic; Demographic aspects; enfants; Female; Fingers - blood supply; Fundamental and applied biological sciences. Psychology; Heart beat; Heart Rate; Human subjects; Humans; Hypertension; Male; Measurement; Models, Cardiovascular; Regression Analysis; sensibilité du baroréflexe; spectral analysis; Spectrum analysis; Vertebrates: anatomy and physiology, studies on body, several organs or systems; âge
• ISSN: 0008-4212; 1205-7541
• DOI: 10.1139/y06-060

The aim of the study was to determine changes of baroreflex sensitivity in humans between 11 and 20 years of age. Continuous 5 min blood pressure recordings using a Finapres were taken in 415 healthy subjects while in a sitting, resting position (breathing at a frequency of 0.33 Hz). Beat-by-beat values of interbeat intervals (IBI) or heart rate, and systolic and diastolic blood pressures were measured. Baroreflex sensitivity in ms/mmHg (BRS) and in mHz/mmHg (BRSf) was determined at an average frequency of 0.1 Hz by spectral analysis. BRS did not correlate with age, but BRSf significantly decreased with age (p < 0.001). BRS correlated with mean IBI (p < 0.001) in all subjects and also in the particular subgroups, but BRSf was IBI-independent. Results of multiregression equations were BRS = 1.37 - 0.56 × age (years) + 0.02 × IBI (ms) (p < 0.001 for BRS vs. age and for BRS vs. IBI);; BRSf = 34.74 - 0.97 × age (years) - 0.001 × IBI (ms) (p < 0.001 only for BRS vs. age), where age was measured in years and IBI was measured in ms. The limits of BRS were estimated for the total group: 5th percentile, 3.9;; 50th percentile, 9.1;; and 95th percentile, 18.7 ms/mmHg; and limits for BRSf were 5th percentile, 8.5;; 50th percentile, 16.4;; and 95th percentile, 33.6 mHz/mmHg. We conclude that IBI-dependent BRS was unchanged in the particular age groups, but the standardization of BRS on IBI decreased with age. BRSf was IBI-independent and better reflected the development of the BRS.