AGE-RELATED CHANGES IN BLOOD PRESSURE, HEART RATE AND BAROREFLEX SENSITIVITY IN SHR

A progressive decline in baroreflex sensitivity (BRS) is a characteristic feature of human aging, the basis of which is poorly understood. The purpose of the present study was to determine whether alterations in efferent baroreflex function might contribute to the age-related decrease in BRS. We studied 10 healthy young (mean age 30.5 years; age range 22–40 years; six male) and 10 healthy elderly (mean age 70.7 years; age range 67–75 years; five male) volunteers. We tested efferent cardiac vagal function using the bradycardiac response to the cold face test, and efferent sympathetic function using heart rate and blood pressure responses to four stress tests: (i) low-level cognitive stress, (ii) high-level cognitive stress, (iii) hand immersion in ice water (cold pressor test) and (iv) isometric sustained hand-grip. Haemodynamic responses to these stresses are mediated via efferent baroreflex pathways, whereas the afferent components of each reflex response are independent of afferent baroreflex pathways. BRS was measured from simultaneous Finapres-derived continuous blood pressure and digital ECG R–R interval data using the sequence analysis paradigm. As expected, BRS was significantly reduced in the elderly group (7.29±0.74 ms/mmHg; mean±S.E.M.) compared with the young group (13.84±1.13 ms/mmHg; P < 0.001). However, neither the bradycardiac responses to the cold face test nor the efferent sympathetically mediated heart rate/blood pressure responses to the stress test battery were significantly different between the young and elderly groups. We conclude that the age-related decrease in BRS is not attributable to impairments in the efferent sympathetic or parasympathetic system components of the baroreceptor reflex pathway.

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Age-Related Changes in Control of Blood Pressure and Heart Rate During Sleep in the Rat

SLEEP ◽

10.1093/sleep/25.3.279 ◽

2002 ◽

Vol 25 (3) ◽

pp. 279-285 ◽

Cited By ~ 19

Author(s):

Hiroyoshi Sei ◽

Atsuko Sano ◽

Hiromi Ohno ◽

Kazue Yamabe ◽

Yasuhiko Nishioka ◽

...

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Age Related ◽

Age Related Changes

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Hemodynamic Patterns of Age-Related Changes in Blood Pressure

Circulation ◽

10.1161/01.cir.96.1.308 ◽

1997 ◽

Vol 96 (1) ◽

pp. 308-315 ◽

Cited By ~ 1210

Author(s):

Stanley S. Franklin ◽

William Gustin ◽

Nathan D. Wong ◽

Martin G. Larson ◽

Michael A. Weber ◽

...

Keyword(s):

Blood Pressure ◽

Age Related ◽

Age Related Changes

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Heart rate and blood pressure variability and baroreflex sensitivity in patients with acute brain injury

Journal of Critical Care ◽

10.1016/j.jcrc.2005.09.048 ◽

2005 ◽

Vol 20 (4) ◽

pp. 394 ◽

Cited By ~ 1

Author(s):

V. Papaioannou ◽

M. Giannakou ◽

N. Maglaveras ◽

E. Sofianos ◽

M. Giala

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Brain Injury ◽

Blood Pressure Variability ◽

Baroreflex Sensitivity ◽

Acute Brain Injury

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Age-Related Changes in Vestibular Evoked Myogenic Potentials Using a Modified Blood Pressure Manometer Feedback Method

American Journal of Audiology ◽

10.1044/1059-0889(2010/10-0021) ◽

2010 ◽

Vol 19 (2) ◽

pp. 100-108 ◽

Cited By ~ 4

Author(s):

Brandon M. Tourtillott ◽

John A. Ferraro ◽

Ali Bani-Ahmed ◽

Elaine Almquist ◽

Nandini Deshpande

Keyword(s):

Blood Pressure ◽

Vestibular Evoked Myogenic Potentials ◽

Age Related ◽

Pressure Manometer ◽

Feedback Method ◽

Age Related Changes

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Effect of heavy exercise on spectral baroreflex sensitivity, heart rate, and blood pressure variability in well-trained humans

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00003.2008 ◽

2008 ◽

Vol 295 (3) ◽

pp. H1150-H1155 ◽

Cited By ~ 24

Author(s):

François Cottin ◽

Claire Médigue ◽

Yves Papelier

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Systolic Blood Pressure ◽

Exercise Test ◽

Blood Pressure Variability ◽

Baroreflex Sensitivity ◽

Low Frequency ◽

Mechanical Effect ◽

Heavy Exercise ◽

Gas Exchange Parameters

The aim of the study was to assess the instantaneous spectral components of heart rate variability (HRV) and systolic blood pressure variability (SBPV) and determine the low-frequency (LF) and high-frequency baroreflex sensitivity (HF-BRS) during a graded maximal exercise test. The first hypothesis was that the hyperpnea elicited by heavy exercise could entail a significant increase in HF-SBPV by mechanical effect once the first and second ventilatory thresholds (VTs) were exceeded. It was secondly hypothesized that vagal tone progressively withdrawing with increasing load, HF-BRS could decrease during the exercise test. Fifteen well-trained subjects participated in this study. Electrocardiogram (ECG), blood pressure, and gas exchanges were recorded during a cycloergometer test. Ventilatory equivalents were computed from gas exchange parameters to assess VTs. Spectral analysis was applied on cardiovascular series to compute RR and systolic blood pressure power spectral densities, cross-spectral coherence, gain, and α index of BRS. Three exercise intensity stages were compared: below (A1), between (A2), and above (A3) VTs. From A1 to A3, both HF-SBPV (A1: 45 ± 6, A2: 65 ± 10, and A3: 120 ± 23 mm2Hg, P < 0.001) and HF-HRV increased (A1: 20 ± 5, A2: 23 ± 8, and A3:40 ± 11 ms2, P < 0.02), maintaining HF-BRS (gain, A1: 0.68 ± 0.12, A2: 0.63 ± 0.08, and A3: 0.57 ± 0.09; α index, A1: 0.58 ± 0.08, A2: 0.48 ± 0.06, and A3: 0.50 ± 0.09 ms/mmHg, not significant). However, LF-BRS decreased (gain, A1: 0.39 ± 0.06, A2: 0.17 ± 0.02, and A3: 0.11 ± 0.01, P < 0.001; α index, A1: 0.46 ± 0.07, A2: 0.20 ± 0.02, and A3: 0.14 ± 0.01 ms/mmHg, P < 0.001). As expected, once VTs were exceeded, hyperpnea induced a marked increase in both HF-HRV and HF-SBPV. However, this concomitant increase allowed the maintenance of HF-BRS, presumably by a mechanoelectric feedback mechanism.

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Somatotypical features of the age dynamics of secondary sexual characteristics and functional parameters in city schoolchildren

Health and Ecology Issues ◽

10.51523/2708-6011.2021-18-2-16 ◽

2021 ◽

pp. 113-118

Author(s):

V. A. Melnik

Keyword(s):

Blood Pressure ◽

Body Type ◽

Age Dynamics ◽

Functional Parameters ◽

Secondary Sexual Characteristics ◽

Age Related ◽

Sexual Characteristics ◽

Age Range ◽

Age Related Changes ◽

Secondary Sexual

Objective: to assess the constitutional features of the age dynamics of secondary sexual characteristics and functional parameters of city schoolchildren in the age range of 7–17 years.Materials and methods. The objects of the study were schoolchildren aged 7–17. The stages of the expression of secondary sexual characteristics were determined visually according to the scheme by J.M. Tanner. The functional parameters of the examined schoolchildren were assessed using the methods of dynamometry, spirometry; blood pressure and heart rates, as well as the time of simple sensorimotor reactions were measured.Results. As a result of the performed studies, it has been found that representatives of the hypersomnic types are ahead of other types to reveal the ﬁrst stages of secondary sexual characteristics. Schoolchildren with the leptosomic morphotypes due to higher rates of their development have reached the deﬁnitive stages by the same age as those with the hypersomnic variants. The intensity of age-related changes in functional parameters (strength qualities, circulatory and respiratory systems, nervous system) in the studied objects depends on their body type.Conclusion. The stage and rate of puberty, as well as the development of functional parameters in city schoolchildren depends on their somatotype.

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Age dependency of cardiovascular autonomic responses to head-up tilt in healthy subjects

Journal of Applied Physiology ◽

10.1152/japplphysiol.00444.2003 ◽

2004 ◽

Vol 96 (6) ◽

pp. 2333-2340 ◽

Cited By ~ 105

Author(s):

Tomi Laitinen ◽

Leo Niskanen ◽

Ghislaine Geelen ◽

Esko Länsimies ◽

Juha Hartikainen

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

High Frequency ◽

Healthy Subjects ◽

Baroreflex Sensitivity ◽

Low Frequency ◽

Upright Position ◽

Vascular Responses ◽

Autonomic Responses ◽

Head Up Tilt

In elderly subjects, heart rate responses to postural change are attenuated, whereas their vascular responses are augmented. Altered strategy in maintaining blood pressure homeostasis during upright position may result from various cardiovascular changes, including age-related cardiovascular autonomic dysfunction. This exploratory study was conducted to evaluate impact of age on cardiovascular autonomic responses to head-up tilt (HUT) in healthy subjects covering a wide age range. The study population consisted of 63 healthy, normal-weight, nonsmoking subjects aged 23–77 yr. Five-minute electrocardiogram and finger blood pressure recordings were performed in the supine position and in the upright position 5 min after 70° HUT. Stroke volume was assessed from noninvasive blood pressure signals by the arterial pulse contour method. Heart rate variability (HRV) and systolic blood pressure variability (SBPV) were analyzed by using spectral analysis, and baroreflex sensitivity (BRS) was assessed by using sequence and cross-spectral methods. Cardiovascular autonomic activation during HUT consisted of decreases in HRV and BRS and an increase in SBPV. These changes became attenuated with aging. Age correlated significantly with amplitude of HUT-stimulated response of the high-frequency component ( r = -0.61, P < 0.001) and the ratio of low-frequency to high-frequency power of HRV ( r = -0.31, P < 0.05) and indexes of BRS (local BRS: r = -0.62, P < 0.001; cross-spectral baroreflex sensitivity in the low-frequency range: r = -0.38, P < 0.01). Blood pressure in the upright position was maintained well irrespective of age. However, the HUT-induced increase in heart rate was more pronounced in the younger subjects, whereas the increase in peripheral resistance was predominantly observed in the older subjects. Thus it is likely that whereas the dynamic capacity of cardiac autonomic regulation decreases, vascular responses related to vasoactive mechanisms and vascular sympathetic regulation become augmented with increasing age.

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