scholarly journals Sleep Efficiency is Inversely Associated with Brachial Artery Diameter and Morning Blood Pressure in Midlife Adults, with a Potential Sex-Effect: A Short Comment [Letter]

2021 ◽  
Vol Volume 13 ◽  
pp. 1875-1876
Author(s):  
Reza Rastmanesh
2021 ◽  
Vol Volume 13 ◽  
pp. 1641-1651 ◽  
Author(s):  
Saurabh S Thosar ◽  
Daniel Chess ◽  
Nicole P Bowles ◽  
Andrew W McHill ◽  
Matthew P Butler ◽  
...  

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 984-984
Author(s):  
Sharon E. Cox ◽  
Julie Makani ◽  
Elizabeth Ellins ◽  
Gurishaeli Walter ◽  
Selemani Mtunguja ◽  
...  

Abstract Introduction Endothelial function is impaired in adults with sickle cell anaemia (SCA), but limited data exists in children. Endothelial damage occurs from chronic inflammation, oxidant damage, immune cell activation and ischemia-reperfusion injury. In addition, availability of nitric oxide (NO) as the major vasodilator may be reduced as a result of scavenging by plasma haemoglobin and reduced arginine substrate for endothelial nitric oxide synthase. Methods Tanzanian children (N=119) with SCA (HbSS) aged 8-11.9 years enrolled in the Vascular Function Intervention Trial (ISRCTN74331412/NCT01718054) underwent baseline assessment of endothelium-dependent and -independent vasodilatation. All children were determined clinically well at assessment, hydroxyurea naive, on no long-term medication and not receiving chronic blood transfusions. Blood pressure and vasomotion were assessed after 10 minutes recumbent rest in a temperature controlled room between 08-13:00 hrs. An identical protocol as published in children (Donald & Charakida et al. Eur Heart J; 2010: 31; 1502-10) was used. In brief, brachial arterial endothelium dependent dilatation was assessed by 1 of 3 trained technicians using ultrasound imaging (Ultrasonix SonixTouch with a 12Mz probe & stereotactic holder) to assess flow-mediated dilatation (FMD) in response to reactive hyperaemia induced after release of transient blood pressure cuff occlusion (5 min, 200 mmHg, Hokanson, USA) using an automated air regulator (Logan Research, UK). Automated B-mode image edge detection was used to measure maximum change in arterial diameter (Brachial Tools) expressed as a percentage of resting baseline diameter (FMDmax). Endothelium-independent responses to 2.5µg sub-lingual glyceryl-trinitrate (GTN) were also assessed. All recordings were over-read by an experienced researcher in the UK. Venepuncture for full blood count, clinical chemistry and amino acids was conducted after FMD assessment. Results Patient characteristics are described in Table 1. Mean brachial artery diameter at baseline was 2.61mm (95% CI 2.55 – 2.67mm). Mean FMDmax was 7.70% (95% CI 7.09 – 8.32%). Endothelium-independent vasodilation (GTNmax) was 4.15% (95% CI 3.83 – 4.47%). The FMDmax response was on greater than the GTNmax response (Figure 1). No effect of room or skin temperature on FMDmax or GTNmax was observed. There was a strong inverse association between baseline artery diameter and FMDmax (-3.46, P<0.001) (Figure 2). The time to peak brachial artery diameter in response to hyperaemia was positively skewed (median 55s (IQR: 43-79s)) and was not associated with FMDmax. The only patient characteristic associated with FMDmax was age with a non-significant inverse correlation (-0.52, P=0.06) but was reduced when adjusting for baseline diameter. Baseline heart rate was positively associated with FMDmax and GTNmax (P=0.01 & 0.025). Discussion We have characterised peripheral vascular function in a large cohort of children with SCA. Mean FMDmax was slightly lower than that observed in predominantly Caucasian non-SCA British children of similar age (8.1% [SD3.4]) (Donald & Charakida et al. Eur Heart J 2010: 31; 1502-10), but higher than reported in 21 older French children with SCA (5.6 +/- 0.2) (Montalembert et al. Haematol 2007: 92; 1709-10) which might reflect deterioration of endothelial function with age. There was no apparent association between FMDmax and hemolytic markers or with nutritional status at baseline. Recruitment and assessment of appropriate local non-SCA controls for comparison is planned. Amino acid analyses are ongoing. Disclosures: No relevant conflicts of interest to declare.


2015 ◽  
Vol 119 (8) ◽  
pp. 858-864 ◽  
Author(s):  
Ceri L. Atkinson ◽  
Howard H. Carter ◽  
Louise H. Naylor ◽  
Ellen A. Dawson ◽  
Petra Marusic ◽  
...  

While the impact of changes in blood flow and shear stress on artery function are well documented, the acute effects of increases in arterial pressure are less well described in humans. The aim of this study was to assess the effect of 30 min of elevated blood pressure, in the absence of changes in shear stress or sympathetic nervous system (SNS) activation, on conduit artery diameter. Ten healthy male subjects undertook three sessions of 30 min unilateral handgrip exercise at 5, 10, and 15% of maximal voluntary contractile (MVC) strength. Brachial artery shear rate and blood flow profiles were measured simultaneously during exercise in the active and contralateral resting arms. Bilateral brachial artery diameter was simultaneously assessed before and immediately postexercise. In a second experiment, six subjects repeated the 15% MVC condition while continuous vascular measurements were collected during muscle sympathetic nerve activity (MSNA) assessment using peroneal microneurography. We found that unilateral handgrip exercise at 5, 10, and 15% MVC strength induced stepwise elevations in blood pressure ( P < 0.01, Δmean arterial pressure: 7.06 ± 2.44, 8.50 ± 2.80, and 18.35 ± 3.52 mmHg, P < 0.01). Whereas stepwise increases were evident in shear rate in the exercising arm ( P < 0.001), no changes were apparent in the nonexercising limb ( P = 0.42). Brachial artery diameter increased in the exercising arm ( P = 0.02), but significantly decreased in the nonexercising arm ( P = 0.03). At 15% MVC, changes in diameter were significantly different between arms (interaction effect: P = 0.01), whereas this level of exertion produced no significant changes in MSNA. We conclude that acute increases in transmural pressure, independent of shear rate and changes in SNS activation, reduce arterial caliber in normotensive humans in vivo. These changes in diameter were mitigated by exercise-induced elevations in shear rate in the active limb.


Physiology ◽  
1990 ◽  
Vol 5 (3) ◽  
pp. 125-127
Author(s):  
GM London ◽  
S Laurent ◽  
ME Safar

Studies using pulsed-Doppler velocimetry reveal that in the absence of changes in blood pressure and heart rate, the human brachial artery dilates on raising the legs from the supine position. The dilatation cannot be explained exclusively by the increase in blood flow and probably involves a reflex from stimulation of cardiopulmonary receptors.


Author(s):  
Natércia Neves Marques de Queiroz ◽  
Franciane Trindade Cunha de Melo ◽  
Fabrício de Souza Resende ◽  
Luísa Corrêa Janaú ◽  
Norberto Jorge Kzan de Souza Neto ◽  
...  

Background: Vitamin D (VD) deficiency has been related to several endocrine metabolic and cardiovascular diseases. Effect of VD supplementation on blood pressure (BP) in patients with diabetes is controversial. Objective: The aim of this study was to evaluate high-dose vitamin D supplementation effects on blood pressure of normotensive type 1 diabetes mellitus (T1DM) patients by 24-hour ambulatory blood pressure monitoring (ABPM). Methods: We performed a clinical trial including 35 T1DM normotensive patients, who received doses of 4,000 or 10,000 IU/day of cholecalciferol for 12 weeks according to previous VD levels. They underwent 24-hour ABPM, along with glycated hemoglobin, creatine, lipids profile and PCRus dosage before and after VD supplementation. Results and discussion: We found an expressive reduction of systolic and diastolic morning blood pressures (117±14 vs 112±14, p<0,05; 74±9 vs 70±10 mmHg, p<0,05, respectively) with no changes in other pressoric markers. Besides, we noticed a relation between levels of VD after supplementation and diastolic morning blood pressure (r= -0,4; p<0.05). Conclusion: Our study suggests an association between supplementation of high doses of vitamin D and the reduction of morning blood pressure in normotensive T1DM patients.


2021 ◽  
Vol 28 (Supplement_1) ◽  
Author(s):  
L Rotheudt ◽  
E Moritz ◽  
M Markus ◽  
H Voelzke ◽  
N Friedrich ◽  
...  

Abstract Funding Acknowledgements Type of funding sources: None. Introduction  Sphingosine-1-phosphate (S1P) is a lipid mediator of the immune system and vascular bed. However, cross-sectional analyses of S1P and parameters of vascular health in the population are sparse. Purpose  We explored the relation between S1P concentrations and several parameters of vascular health, i.e. ankle-brachial index (ABI), carotid intima-media thickness (cIMT), presence of carotid atherosclerotic plaques/stenosis, brachial artery flow-mediated dilation (FMD) as well as aortic wall thickness (AWT). Methods S1P was measured by liquid chromatography-tandem mass spectrometry in the population-based Study of Health in Pomerania (SHIP-TREND-0). ABI was calculated as the ratio of systolic blood pressure in arms and ankles. For cIMT, the distance between the lumen-intima and media-adventitia interfaces in longitudinal scans were measured. Carotid plaques were defined as a focal protrusion of the carotid vessel wall. Carotid stenosis was assessed with Doppler ultrasonography. FMD was evaluated by measuring the increase in brachial artery diameter after transient forearm ischemia. AWT was assessed by Magnetic Resonance Imaging.  Subjects with cancer, severe renal insufficiency, previous myocardial infarction and extreme values for S1P (&lt; 1st and &gt; 99th percentile) were excluded. Sex stratified linear regression models adjusted for age, smoking, waist-to-hip ratio and platelets were used to assess the relation between S1P and vascular disease parameters. Results A total of n = 3,643 participants (48% male, median age 51, 25th and 75th percentile 39 and 63 years) could be included in the analyses. The median S1P concentration was 0.788 µM (25th and 75th percentile 0.679 and 0.906, respectively). In men a 1 standard deviation higher S1P was associated with a significantly greater cIMT (β: 0.0057 95% confidence interval [CI]: 0.00027 to 0.0112 mm; p = 0.0396) and a lower ABI (β: -0.0090 (95% confidence interval [CI]: -0.0153 to -0.0029; p = 0.0038. In women S1P was significantly associated with cIMT (β: 0.0044 95% confidence interval [CI]: 0.0001 to 0.0086 mm; p = 0.0445) while no significant association was found for the relation of S1P with ABI. For both men and women S1P was not associated with FMD, the presence of carotid plaques/stenosis and AWT. Conclusions We found that S1P concentrations were positively related to a thicker cIMT in both sexes and lower ABI values in men. There was no association of S1P with any of the other vascular markers of interest. Future studies need to validate our results in other populations.


2006 ◽  
Vol 110 (4) ◽  
pp. 475-482 ◽  
Author(s):  
Mikko J. Järvisalo ◽  
Laura Jartti ◽  
Jukka Marniemi ◽  
Tapani Rönnemaa ◽  
Jorma S. A. Viikari ◽  
...  

Brachial artery FMD (flow-mediated dilatation) is widely used as a marker of systemic arterial endothelial function. FMD, however, shows considerable 25% day-to-day variation that hinders its clinical use. The reasons for this variability are poorly characterized. Therefore the present study was designed to clarify factors responsible for the hourly variation in endothelial function, including consuming a low-fat meal and circadian rhythms in endogenous hormonal levels. Brachial artery FMD, along with serum glucose, triacylglycerols (triglycerides) and levels of several hormones were measured six times per day on two separate days 1 week apart. On one day, the subjects (healthy males: n=12, mean age, 24 years) ate a light breakfast and a standardized lunch (23.5% fat, 48.7% carbohydrate and 27.8% protein). On the other day, they had a similar breakfast after which they fasted. Postprandial FMD values (both after breakfast and after lunch) were similar to baseline FMD. FMD showed a 28% hourly variation and 27% weekly variation. Variation in plasma levels of insulin (P=0.02) associated negatively and DHPG (3,4-dihydroxyphenylglycol) (P=0.001), a marker of sympathetic nervous activation, associated positively with variation in FMD. The effects of DHPG and insulin on FMD were independent of changes in baseline brachial artery diameter, although DHPG was also inversely associated with baseline diameter. Eating a regular low-fat meal does not have any measurable effects on brachial artery endothelial function. These data suggest that strict requirements for fasting conditions may be unnecessary when measuring peripheral endothelial function using the ultrasound technique. Circadian variation in serum insulin and sympathetic tone are physiological determinants of endothelial function.


2006 ◽  
Vol 290 (4) ◽  
pp. H1446-H1453 ◽  
Author(s):  
Kenneth S. Dyson ◽  
J. Kevin Shoemaker ◽  
Richard L. Hughson

We tested the hypothesis that flow-mediated dilation (FMD) of the brachial artery would be impaired by acute increases in sympathetic nervous system activity (SNA) in models where similar peak shear stress stimulus was achieved by varying the duration of forearm muscle ischemia. Eleven healthy young men were studied under four different conditions, each with its own control: lower body suction (LBS), cold pressor test (CPT), mental arithmetic task (MAT), and activation of muscle chemoreflex (MCR). The duration of ischemia before observation of FMD by ultrasound imaging was 5 min each for control, LBS, and CPT; 3 min for MAT; and 2-min for MCR. Peak shear rate was not different between control and any of the SNA conditions, although total shear in the first minute was reduced in MAT. MCR was the only condition in which brachial artery vasoconstriction was observed before forearm occlusion [4.38 (SD 0.53) vs. control 4.60 (SD 0.53) mm, P < 0.05]; however, diameter increased to the same absolute value as that of the control, so the percent FMD was greater for MCR [9.85 (SD 2.33) vs. control 5.29 (SD 1.50)%]. Blunting of the FMD response occurred only in the CPT model [1.51 (SD 1.20)%]. During SNA, the increase in plasma cortisol from baseline was significant only for MCR; the increase in plasma norepinephrine was significant for MCR, LBS, and CPT; and the increase in epinephrine was significant only for MCR. These results showed that the four models employed to achieve increases in SNA had different effects on baseline brachial artery diameter and that blunted FMD is not a general response to increased SNA.


Sign in / Sign up

Export Citation Format

Share Document