Age-dependent relationship between the carotid intima-media thickness, baroreflex sensitivity, and the inter-beat interval in normotensive and hypertensive subjects.

Abstract

The interrelationship between baroreflex sensitivity expressed in ms/mm Hg (BRS) or in Hz/mm Hg (BRSf), carotid wall thickness (IMT), and age was investigated in hypertensive and normotensive subjects with respect to the mean inter-beat interval (IBI) and blood pressure (BP). BP monitoring was performed in 25 treated hypertensives (Hy; 47.4±9.2 years of age) and 23 normotensives (Norm; 44.5±8.1 years). IMT was measured by ultrasonography. BRS and BRSf were determined by the spectral method (five-minute non-invasive beat-to-beat recording of BP and IBI, Finapres, controlled breathing at a frequency of 0.33 Hz). Significant differences between Hy and Norm were detected in IMT (Hy: 0.624±0.183, Norm: 0.522±0.070 mm; p<0.01), BRS (Hy: 3.5±1.6, Norm: 5.7±2.3 ms/mm Hg; p<0.01), BRSf (Hy: 0.005±0.002, Norm: 0.009±0.004 Hz/mm Hg; p<0.01), systolic BP (Hy: 131±21, Norm: 116±17 mm Hg; p<0.01) and diastolic BP (Hy: 77±16, Norm: 64±12 mm Hg; p<0.01). A significant correlation was found between age and IMT (Norm: 0.523, p<0.05; Hy+Norm: 0.419, p<0.01), age and BRS (Norm: -0.596, p<0.01; Hy+Norm: -0.496, p<0.01), age and BRSf (Norm: -0.555, p<0.01; Hy: -0.540, p<0.01; Hy+Norm: -0.627, p<0.01), age and IBI (Hy: 0.478, p<0.05), age and diastolic BP (Hy: -0.454, p<0.05), BRS and IMT (Hy+Norm: -0.327, p<0.05) and BRSf and IMT (Hy+Norm: -0.358, p<0.05). Hypertensive patients have increased IMT and decreased BRS and BRSf. The positive correlation between age and IMT and the negative correlation between age and BRS and BRSf are in agreement with the hypothesis that the age-dependent decrease of baroreflex sensitivity corresponds to the age-related structural changes of the carotid wall. Using two indices of baroreflex sensitivity, BRS and BRSf, we could show that baroreflex sensitivity in hypertensives is lower not only due to thickening of the carotid wall, but also due to aging.

Heart Rate from Progressive Volitional Cycling Test Is Associated with Endothelial Dysfunction Outcomes in Hypertensive Chilean Adults

“…It seems that the link between cIMT and the attenuated chronotropic response to exercise is the imbalance of the sympathovagal activation, which reflects the baroreflex sensitivity dysfunction. This dysfunction has been described as a probable cause of early atherosclerosis risk factors such as inflammation [29,30]. Therefore, an impaired chronotropic response to exercise could be an indicator of the EDys presence in subjects without cardiovascular risk factors, including HTN, as we found [28].…”

Non-invasive parameters of autonomic function using beat-to-beat cardiovascular variations and arterial stiffness in hypertensive individuals: a systematic review

“…Table 2 summarizes the characteristics of selected studies. Two of the 19 studies are longitudinal studies [ 40 , 42 ], 11 are case–control studies [ 20 , 35 , 37 , 39 , 43 , 44 , 46 – 48 , 50 , 51 ], while the remaining are cohort studies which only involve the hypertension group [ 34 , 36 , 38 , 41 , 45 , 49 ]. 15 studies involved participants with a mean age ranging from 40 to 65 years [ 20 , 34 – 37 , 39 – 44 , 46 , 48 – 50 ], while three studies recruited older individuals aged above 65 years [ 45 , 47 , 51 ].…”

“…Two of the 19 studies are longitudinal studies [ 40 , 42 ], 11 are case–control studies [ 20 , 35 , 37 , 39 , 43 , 44 , 46 – 48 , 50 , 51 ], while the remaining are cohort studies which only involve the hypertension group [ 34 , 36 , 38 , 41 , 45 , 49 ]. 15 studies involved participants with a mean age ranging from 40 to 65 years [ 20 , 34 – 37 , 39 – 44 , 46 , 48 – 50 ], while three studies recruited older individuals aged above 65 years [ 45 , 47 , 51 ]. Of all included studies, 12 included both normotensive control and essential hypertensive subjects [ 43 ], with both mixed genders involved [ 20 , 35 , 37 , 39 , 40 , 44 , 46 – 48 , 50 , 51 ], whereas one study investigated the association between autonomic control and vascular condition in men with essential hypertension only [ 38 ].…”

“…15 studies involved participants with a mean age ranging from 40 to 65 years [ 20 , 34 – 37 , 39 – 44 , 46 , 48 – 50 ], while three studies recruited older individuals aged above 65 years [ 45 , 47 , 51 ]. Of all included studies, 12 included both normotensive control and essential hypertensive subjects [ 43 ], with both mixed genders involved [ 20 , 35 , 37 , 39 , 40 , 44 , 46 – 48 , 50 , 51 ], whereas one study investigated the association between autonomic control and vascular condition in men with essential hypertension only [ 38 ]. Some involved only hypertensive subjects in their study [ 34 , 36 , 49 ].…”

“…Finapres ® : SBP, DBP, RRI 2. B-mode ultrasonography: carotid IMT Labrova et al [ 39 ] 2005 n = 23 (7 men); age: 44.5 ± 8.1 years n = 25 (11 men); age: 47.4 ± 9.2 years; treated, essential hypertension SBP ≥ 140 mm Hg and/or DBP ≥ 90 mm Hg 1. Finapres ® : SBP, DBP, RRI 2.…”