Diurnal Blood Pressure Variation Research Articles

Effects of isometric leg training on ambulatory blood pressure and morning blood pressure surge in young normotensive men and women

Despite the reported association between diurnal variations in ambulatory blood pressure (BP) and elevated cardiovascular disease risk, little is known regarding the effects of isometric resistance training (IRT), a practical BP-lowering intervention, on ambulatory BP and morning BP surge (MBPS). Thus, we investigated whether (i) IRT causes reductions in ambulatory BP and MBPS, in young normotensives, and (ii) if there are any sex differences in these changes. Twenty normotensive individuals (mean 24-h SBP = 121 ± 7, DBP = 67 ± 6 mmHg) undertook 10-weeks of bilateral-leg IRT (4 × 2-min/2-min rest, at 20% maximum voluntary contraction (MVC) 3 days/week). Ambulatory BP and MBPS (mean systolic BP (SBP) 2 h after waking minus the lowest sleeping 1 h mean SBP) was measures pre- and post-training. There were significant reductions in 24-h ambulatory SBP in men (− 4 ± 2 mmHg, P = 0.0001) and women (− 4 ± 2 mmHg, P = 0.0001) following IRT. Significant reductions were also observed in MBPS (− 6 ± 8 mmHg, p = 0.044; − 6 ± 7 mmHg, P = 0.019), yet there were no significant differences between men and women in these changes, and 24-h ambulatory diastolic BP remained unchanged. Furthermore, a significant correlation was identified between the magnitude of the change in MBPS and the magnitude of changes in the mean 2-h SBP after waking for both men and women (men, r = 0.89, P = 0.001; women, r = 0.74, P = 0.014). These findings add further support to the idea that IRT, as practical lifestyle intervention, is effective in significantly lowering ambulatory SBP and MBPS and might reduce the incidence of adverse cardiovascular events that often occur in the morning.

Diurnal blood pressure variation in adults after abdominal surgery–An observational cohort study

ObjectiveTo describe the prevalence of various circadian blood pressure patterns in adults recovering from abdominal surgery, and to evaluate the association between loss of normal circadian variation in blood pressure and hypotension during the initial 2 postoperative days. DesignA post-hoc analysis of data obtained from two randomized trials. SettingOperating rooms of the Cleveland Clinic. PatientsAdults having abdominal surgery from 2015 to 2019 with at least one overnight stay. Participants were continuously monitored by wearable vital signs monitors starting in the post-anesthesia care unit and for the first 48 postoperative hours. InterventionsNone. The exposure of interest was the degree of nocturnal decrease in blood pressure - normal nocturnal decrease in blood pressure (“normal dipping”, more than 10% decrease compared to day-time), no nocturnal decrease (“non-dipping”, less than 10% nocturnal decrease), or nocturnal increase in blood pressure (“rising”). MeasurementsPostoperative hypotension, defined by the time weighted average (TWA) area under a mean arterial pressure (MAP) threshold of 70 mmHg. ResultsIn total, 590 patients were eligible for analysis (mean(SD) age 50(15) years, 56% females, median [IQR] surgery duration 4.0 [2.7, 5.8] hours). Median TWA area under a MAP threshold of 70 mmHg was 0.96 (95%CI 0.59, 1.33) mmHg*minute per monitoring hour lower in patients with either no nocturnal blood pressure decrease (N = 317, 54%), or an increase in nocturnal blood pressure (N = 211, 36%), than in the reference group of patients with normal nocturnal decrease (N = 62, 11%), P < 0.001 for both. ConclusionsAbnormal diurnal blood pressure patterns are common in adults during the initial 2 days after abdominal surgery. Lack of normal night-time decrease in blood pressure is associated with less postoperative hypotension. Future studies should evaluate whether abnormal postoperative diurnal blood pressure patterns are associated with worse outcomes.

Blood pressure variability, endothelial dysfunction, and C-reactive protein levels in arterial hypertension in combination with coronary artery disease

Background. Recently, the role of increased variability in blood pressure (BP) as a new risk factor for cardiovascular events in patients with arterial hypertension (AH) in combination with coronary heart disease (CHD) has been discussed. At the same time, the mechanisms of the participation of blood pressure variability in the development of atherosclerotic damage to the vascular wall are not well understood.&#x0D; Aim. To study the nature of the relationship between the indicators of daily BP variability, vasomotor function of the endothelium and highly sensetive C-reactive protein (hs-CRP) in patients with AH combined with CAD.&#x0D; Materials and methods. 80 patients with AH and CAD (55.50.7 years) were examined. The study assessed the BP variability according to 24-hour monitoring of BP, vasomotor function of the brachial artery endothelium, and the level hs-CRP in blood serum.&#x0D; Results. Increased indicators of diurnal BP variability were recorded in 48.8% of patients. There were revealed signs of endothelial dysfunction in patients in the form of a decrease in endothelium-dependent vasodilation (EDV) to 5.380.48% and an insufficient increase in endothelium-independent vasodilation (EIV) to 15.821.24%. Patients with increased variability of BP differed from patients with normal variability of BP by higher values of hs-CRP (2.980.71 and 1.560.33 mg/l; p0.05), a less pronounced response to administration nitroglycerin when evaluating EIV (13.231.79 and 17.700.77%; p0.05). Correlation relationships of variability of systolic BP (SBP) in the daytime with EVD were recorded (r=-0.44; p=0.012); variability of diastolic BP (DBP) in the daytime with EIV (r=-0.50; p=0.003); nighttime variability of DBP with EIV (r=-0.43; p=0.013). Relationships between the level of hs-CRP and the variability of SBP in the daytime (r=0.30; p=0.008) and with EVD (r=-0.47; p=0.007) were established. In patients with increased variability of SBP, the likelihood of registering an increased level of hs-CRP is 1.6 times higher OR 1.58 (95% CI 1.0142.451; p=0.043). In patients with depletion of the vasodilation reserve during the test with nitroglycerin (EIV), an increase in blood pressure variability is recorded 1.2 times more likely OR 1.22 (95% CI 1.0121.478; p=0.037).&#x0D; Conclusion. The revealed association of the daily variability of BP with indicators of vasomotor function of the endothelium and a marker of the inflammatory reaction of the vascular wall may indicate the presence of a pathogenetic relationship between the parameters that determine the development of adverse events in patients with AH and CAD.

The pattern of systemic inflammation index in normotensive non-dipper and dipper hypertensive patients

Objective: Continuous inflammation at the level of the vascular endothelium plays an important role in the formation of hypertension. Diurnal blood pressure (BP) variation also is a risk factor for hypertensive target organ damage. This study planned to evaluate these inflammation processes in normotensive and hypertensive patients. Methods: This study is observational cross-sectional cohort in-design. 151 patients with a prediagnosis of hypertension included. The patients were divided into three groups (group 1: dipper normotensive, group 2: non-dipper normotensive, group 3: dipper-hypertensive) based on the results of ambulatory blood pressure monitoring. The groups were compared in terms of systemic inflammation index (SII; platelet count×neutrophil count/lymphocyte count), neutrophil to lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and other inflammation processes. Results: There was a significant difference between the three groups in terms of mean platelet volume (MPV) and red blood cell distribution width (RDW) levels (p=0.001 and p&amp;lt;0.001, respectively). A statistically significant difference was found between the groups in terms of NLR, PLR, systemic inflammation index, lymphocyte-monocyte ratio (LMR). In subgroup analysis, NLR and systemic inflammation index were similar in group 2 and group 3, but higher than in group 1 in both groups. LMR was similar in group 2 and group 3 but lower than in group 1. In subgroup analysis PLR levels were similar in group 2 and group 3 but higher than group 1 in both groups. Conclusion: This study showed that normotensive non-dipper patients had inflammation as much as dipper hypertensive patients according to measurement of MPV, RDW systemic inflammation index, PLR, NLR levels.

Salt sensitivity of volume and blood pressure in a mouse with globally reduced ENaC γ-subunit expression.

The epithelial Na+ channel (ENaC) promotes the absorption of Na+ in the aldosterone-sensitive distal nephron, colon, and respiratory epithelia. Deletion of genes encoding subunits of ENaC results in early postnatal mortality. Here, we present the initial characterization of a mouse with dramatically suppressed expression of the ENaC γ-subunit. We used this hypomorphic (γmt) allele to explore the importance of this subunit in homeostasis of electrolytes and body fluid volume. At baseline, γ-subunit expression in γmt/mt mice was markedly suppressed in the kidney and lung, whereas electrolytes resembled those of littermate controls. Aldosterone levels in γmt/mt mice exceeded those seen in littermate controls. Quantitative magnetic resonance measurement of body composition revealed similar baseline body water, lean tissue mass, and fat tissue mass in γmt/mt mice and controls. γmt/mt mice exhibited a more rapid decline in body water and lean tissue mass in response to a low-Na+ diet than the controls. Replacement of drinking water with 2% saline selectively and transiently increased body water and lean tissue mass in γmt/mt mice relative to the controls. Lower blood pressures were variably observed in γmt/mt mice on a high-salt diet compared with the controls. γmt/mt also exhibited reduced diurnal blood pressure variation, a "nondipping" phenotype, on a high-Na+ diet. Although ENaC in the renal tubules and colon works to prevent extracellular fluid volume depletion, our observations suggest that ENaC in other tissues may participate in regulating extracellular fluid volume and blood pressure.NEW & NOTEWORTHY A mouse with globally suppressed expression of the epithelial Na+ channel γ-subunit showed enhanced sensitivity to dietary salt, including a transient increase in total body fluid, reduced blood pressure, and reduced diurnal blood pressure variation when given a dietary NaCl challenge. These results point to a role for the epithelial Na+ channel in regulating body fluid and blood pressure beyond classical transepithelial Na+ transport mechanisms.

The Association of Morning Surge and Night-Time Dipping Blood Pressure with Significant and Complex Coronary Artery Lesions.

Hypertension responsible for more than 10 million deaths annually worldwide and abnormal diurnal blood pressure (BP) variation is associated with cardiovascular events. This study aimed to investigate the association between the 24-h ambulatory night BP dipping and morning BP surge (MS) with characteristic of coronary artery lesions that may contribute cardiovascular events and mortality burden. A cross sectional study over 1-year, collected 263 cases of hypertensive (80%) and non-hypertensive patients, aged 61 ± 10 years, who undergoing invasive coronary angiography (CAG) and 24-h ambulatory BP monitoring admitted to cardiology department complain of chest pain. The night-time/day-time dip and sleep-trough MS were calculated. Non-dipper status was considered when night-time/day-time dip < 10%, and significant coronary lesion (SCL) when ≥ 50 % stenosis in 1.5 mm vessels. The SYNTAX (Synergy Between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery) score was used to quantify the complexity of SCL. The mean morning systolic BP (SBP) surge was higher in the high SYNTAX Score subgroup than low and intermediate subgroups (25 ± 11 vs 17 ± 13 and 10 ± 10 mmHg, p < 0.010). Non-dipper SBP status was more frequently in patients with SCL than non-SCL (p < 0.019). In ordinal regression, hypertension was independent predictor of SCL (odd ratio: 0.40, p < 0.003), the night-time/day-time BP dip was independent predictor of being in a higher SYNTAX score subgroup (systolic odd ratio: 0.88, diastolic odd ratio: 1.14 p < 0.05). Hypertension is associated with SCL and the night-time/day-time BP dip as a continuous variable is associated with complex coronary lesion. Non-dipping as categorical variable and morning BP surge were not independent predictors of significant or complex coronary lesions.

Serum Uric Acid, Lipid Profile and Atherogenic Index of Plasma in Dipper and Non-dipper Normotensive Subjects

The cardiovascular risk evidentially found to have an association with disparities of the dipper and non-dipper hypertension. There is less celerity with regard to mechanism of diurnal blood pressure variations and related disorders. The serum uric acid and AIP are considered as cardiovascular risk factors. The current study aims to determine and compare serum uric acid level and atherogenic index of plasma (AIP) in dipper and non-dipper normotensive subjects. The study population is 64 healthy normotensive subjects (32 dippers and 32 non-dippers), age between 30-55 years. The subjects were identified into dippers and non-dippers by using ambulatory blood pressure monitoring device (Spacelabs 90207, USA). After identifying dipping status of the subjects, uric acid, triglycerides and HDL cholesterol were measured. AIP was calculated by using formula (log [TG/HDL]). Median (interquartile range) of serum uric acid in the dipper group was 5.08mg/dl (4.12-5.66) and the non-dipper group was 5.27mg/dl (4.63-6.33). The median (interquartile range) for AIP was 0.24 (0.05-0.38) in the dipper group and 0.48 (0.32-0.67) in the non-dipper group. The median (interquartile range) of uric acid and AIP in the non-dipper group was significantly higher than that of dipper group (p&lt;0.05). This study observed in even normotensive subjects, the non-dipper group has significantly higher serum uric acid and AIP than that of dipper group. These cardiovascular risk factors increased in non-dipper group compared to dipper group. The study come out with concluded that non-dipper group had higher cardiovascular risk than dipper group even in normotensive healthy subjects.

Genetic variants of GRK4 influence circadian rhythm of blood pressure and response to candesartan in hypertensive patients

ABSTRACT Background: Genetic variants of coding genes related to blood pressure regulation participate in the pathogenesis of hypertension and determines the response to specific antihypertensive drugs. G protein-coupled receptor kinase 4 (GRK4) and its variants are of great importance in pathogenesis of hypertension. However, little is known about role of GRK4 variants in determine circadian rhythm of blood pressure and response to candesartan in hypertension. The aim of this study was to analyze the correlation of GRK4 variants and circadian rhythm of blood pressure, and to explore their effect on antihypertensive efficiency of candestartan. Methods: In this study, a total of 1239 cases were eligible, completed ambulatory blood pressure monitoring (ABPm) observation and exon sequencing of G protein-coupled receptor kinase 4 (GRK4). ABPm was obtained before and after 4-week treatment of candesartan. Diurnal variation of systolic blood pressure and antihypertensive effect of candesartan were then assessed. Results: Compared to GRK4 wild type (GRK4-WT), patients with GRK4 variants were more likely to be non-dippers (odds ratio (OR) 6.672, 95% confidence interval (CI) 5.124–8.688, P < .001), with GRK4 A142V (OR 5.888, 95% CI 4.332–8.003, P < .001), A486V (OR 7.102, 95% CI 5.334–9.455, P < .001) and GRK4 R65L (OR 3.273, 95% CI 2.271–4.718, P < .001), respectively. Correlation analysis revealed that non-dippers rhythm of blood pressure were associated with GRK4 variants (r = .420, P < .001), with GRK4 A142V (r = .416, P < .001), A486V (r = .465, P < .001) and GRK4 R65L (r = .266, P < .001), respectively. When given 4-week candesartan, patients with GRK4 variants showed better antihypertensive effect as to drop in blood pressure (24 h mSBP, 21.21 ± 4.99 vs 12.34 ± 4.78 mmHg, P < .001) and morning peak (MP-SBP, 16.54 ± 4.37 vs 11.52 ± 4.14 mmHg, P < .001), as well as greater increase in trough to peak ratio (SBP-T/P, .71 ± .07 vs .58 ± .07, P < .001) and smoothness index (SBP-SI, 1.44 ± .16 vs 1.17 ± .11, P < .001) than those with GRK4 WT. Conclusion: This study indicates that hypertensive patients with GRK4 variants are more likely to be non-dippers. What’s more, patients with GRK4 variants possess a significantly better antihypertensive response to candesartan than those with GRK4 WT.

ARTERIAL STIFFNESS AND MALNUTRITION BUT NOT ABPM ARE ASSOCIATED WITH ALL-CAUSE MORTALITY IN PATIENTS UNDERGOING CHRONIC HEMODIALYSIS

Objective: Our aim was to analyze association of diurnal variations of blood pressure with all-cause and cardiovascular (CV) mortality in patients undergoing chronic hemodialysis during a follow-up of 48 months. Design and method: A total of 126 HD patients (74m 52w; average age 61.5 ± 15.8) were enrolled. All patients were dialysed by European and KDIGO guidelines. ABPM (24-hours) was performed with SpaceLab 90207 after mid-week dialysis; pulse wave velocity (PWV) and aortic augmentation index (AIx) were measured using Arteriograph after mid-week dialysis. Malnutrition-inflammation score (MIS) and protein energy wasting (PEW) score were calculated in all enrolled patients. There were 67.6% of patients without prior CV disease, and prior coronary heart disease, valvular disease, atrial fibrillation, stroke, and peripheral arterial disease were diagnosed in 7.1%, 5,6%, 4.7%, 8.7%, 3.9% patients, respectively. Prior diabetes and prior hypertension were diagnosed in 26.2% and 92.4%, respectively. Results: There were 74.6% of non-dippers, while white coat hypertension and masked hypertension were diagnosed in 25.4% and 7.9%, respectively. During the follow up period of 48 months 69 patients died from all-cause and 53 from CV mortality. Diurnal variations of blood pressure were not associated with all-cause mortality. Neither white-coat nor masked hypertension were associated with all-cause mortality. Patients with arterio-venous fistula showed significantly better survival when compared to patients with permanent dialysis catheters and in the linear regression model MIS/PEW and PWV were the only predictors of longer survival (b = −0.371, p = 0.001; b = −0.249, p = 0.009). Conclusions: Blood pressure characteristics (ABPM) were not predictors of all-cause mortality in patients undergoing chronic hemodialysis. On contrary, arterial stiffness and malnutrition were associated with shorter survival. Observed better survival of patients with A-V fistula compared to patients with permanent catheter is very probably reverse epidemiology. Due to small number of CV deaths we were not able to perform analyzes of CV deaths.

PRESENT RECOMMENDED REGIMEN FOR HOME BLOOD PRESSURE MONITORING MAY NEED REVISION FOR ACCURATE MONITORING AND DIAGNOSIS OF HYPERTENSION

Objective: Recent NICE guidelines for management of hypertension stress the importance of home blood pressure management (HBPM) to confirm a diagnosis of hypertension. The objectives were to investigate the difference in two subsequent blood pressure (BP) measurements, evaluate diurnal variation using home blood pressure measurement and assess change in BP levels during a standard measurement period in home environment. Design and method: A total of 758 (male 372/female 386, mean age 57.9 ± 8.2 years) treated for primary hypertension were investigated. No intervention was given during the trial period. BP values were obtained by self-measurement at home using a Bluetooth-equipped oscillometric BP monitor connected to a smartphone application (Accumbo AB). For the first two weeks of the trial, participants were asked to measure HBPM on at least seven days in the morning (before breakfast) and at least seven days in the evening. Each measurement consisted of two BP measurements at 1-minute intervals. Results: The second/subsequent BP measurement showed lower values for both systolic BP (mean SBP 135 ± 12 mmHg vs. 134 ± 12 mmHg) and diastolic blood pressure (mean DBP 88 ± 9 mmHg vs. 87 ± 9 mmHg) compared with the first measurement (p &lt; 0.001). Difference was more pronounced for SBP in males (-0.65 mmHg) than females (-0.52 mmHg), (p &lt; 0.05). Diurnal BP variation was non-significant for SBP (p = 0.18) while DBP showed higher values in the morning (89 ± 9 mmHg) compared with evening values (86 ± 9 mmHg), (p &lt; 0.001). The BP morning surge was more pronounced for males vs. females (p &lt; 0.001). Mean BP was lower during the second week (134/87 ± 12/9 mmHg) compared with the first week (135/88 ± 12/9 mmHg, p &lt; 0.001). This difference was driven by a reduction in BP significant for women (p &lt; 0.001), but not for men (p = 0.37). Conclusions: The results indicate significant gender related differences in subsequent blood pressure values over time which might affect decision for treatment. The guidelines for home blood pressure monitoring may need to be revised to include more measurements over a longer period considering gender affiliation.

EFFECT OF MINERALOCORTICOID RECEPTOR BLOCKER, ESAXERENONE, ON NOCTURNAL HYPERTENSION: A POST HOC ANALYSIS OF ESAX-HTN STUDY

Objective: Nocturnal hypertension is an important phenotype of abnormal diurnal blood pressure variability and a known risk marker for target organ damage and cardiovascular events. Esaxerenone is a novel, first non-steroidal mineralocorticoid receptor blocker (MRB) with a dose-dependent antihypertensive effect. We investigated the efficacy of esaxerenone on nocturnal hypertension in Japanese hypertensive patients. Design and method: The ‘Esaxerenone compared to Eplerenone in Patients with Essential Hypertension (ESAX-HTN)’ study was a phase 3, multicenter, randomized, controlled, double-blind, and parallel-group clinical study conducted in Japan. Patients were eligible for enrolment in the study if they had trough systolic BP (SBP) &gt; = 140 and &lt; 180 mmHg, trough diastolic BP (DBP) &gt; = 90 and &lt; 110 mmHg, 24-hour mean BP (ABPM) &gt; = 130/80 mmHg. This post hoc analysis used ABPM data to evaluate the effects of esaxerenone and eplerenone on nocturnal blood pressure in patients with essential hypertension. Results: Patients (n = 1001) were randomized to esaxerenone 2.5 mg/day (n = 331) or 5 mg/day (n = 338), or eplerenone 50 mg/day (n = 332). Esaxerenone significantly lowered blood pressure from baseline throughout the 24-hour dosing interval; reductions in nighttime systolic blood pressure (95% confidence interval [CI]) were significantly greater with 2.5 and 5 mg/day esaxerenone versus eplerenone (-2.6 mmHg [-5.0, -0.2] and -6.4 mmHg [-8.8, -4.0], respectively). Esaxerenone 2.5 and 5 mg/day significantly reduced nighttime blood pressure from baseline compared with eplerenone in non-dipper patients (-4.4 mmHg [-8.6, -0.2] and -10.8 mmHg [-15.0, -6.7], respectively). In addition, esaxerenone did not markedly alter nighttime blood pressure in extreme dipper patients. In the esaxerenone 5 mg/day group, esaxerenone-induced decreases in nighttime blood pressure were greater than eplerenone-induced decreases in older patients. Conclusions: Esaxerenone may be an effective treatment option for nocturnal hypertension, especially in older patients and those with non-dipping patterns of nocturnal blood pressure.

Arterial Blood Pressure Variability and Other Vascular Factors Contribution to the Cognitive Decline in Parkinson’s Disease

Dementia is one of the most disabling non-motor symptoms in Parkinson’s disease (PD). Unlike in Alzheimer’s disease, the vascular pathology in PD is less documented. Due to the uncertain role of commonly investigated metabolic or vascular factors, e.g., hypertension or diabetes, other factors corresponding to PD dementia have been proposed. Associated dysautonomia and dopaminergic treatment seem to have an impact on diurnal blood pressure (BP) variability, which may presumably contribute to white matter hyperintensities (WMH) development and cognitive decline. We aim to review possible vascular and metabolic factors: Renin-angiotensin-aldosterone system, vascular endothelial growth factor (VEGF), hyperhomocysteinemia (HHcy), as well as the dopaminergic treatment, in the etiopathogenesis of PD dementia. Additionally, we focus on the role of polymorphisms within the genes for catechol-O-methyltransferase (COMT), apolipoprotein E (APOE), vascular endothelial growth factor (VEGF), and for renin-angiotensin-aldosterone system components, and their contribution to cognitive decline in PD. Determining vascular risk factors and their contribution to the cognitive impairment in PD may result in screening, as well as preventive measures.

Characteristics of hypertension in obstructive sleep apnea: An Asian experience.

Obstructive sleep apnea (OSA) is a risk of hypertension and is associated with cardiovascular disease (CVD) incidence. In Asian countries, the prevalence of OSA is high, as in Western countries. When blood pressure (BP) is evaluated in OSA individuals using ambulatory BP monitoring (ABPM), the BP phenotype often indicates abnormal BP variability, such as increased nighttime BP or abnormal diurnal BP variation, that is, non‐dipper pattern, riser pattern, and morning BP surge, and all these conditions have been associated with increased CVD events. Asians have a higher prevalence of increased nighttime BP or morning BP surge than Westerners. Therefore, this review paper focused on OSA and hypertension from an Asian perspective to investigate the importance of the association between OSA and hypertension in the Asian population. Such abnormal BP variability has been shown to be associated with progression of arterial stiffness, and this association could provoke a vicious cycle between abnormal BP phenotypes and arterial stiffness, a phenomenon recognized as systemic hemodynamic atherothrombotic syndrome (SHATS). OSA may be one of the background factors that augment SHATS. An oxygen‐triggered nocturnal oscillometric BP measurement device combined with a pulse oximeter for continuous SpO2 monitoring could detect BP variability caused by OSA. In addition to treating the OSA, accurate and reliable detection and treatment of any residual BP elevation and BP variability caused by OSA would be necessary to prevent CVD events. However, more detailed detection of BP variability, such as beat‐by‐beat BP monitoring, would further help to reduce CV events.

Diurnal Blood Pressure and Heart Rate Variability in Hypertensive Patients with Cerebral Small Vessel Disease: A Case-Control Study

BackgroundWhether autonomic dysfunction contributes to cerebral small vessel disease (CSVD) remains unclear. This study aimed to explore the relationship between CSVD and blood pressure variability (BPV) and heart rate variability (HRV). MethodsThis case-control study recruited 50 patients with CSVD and 50 non-CSVD hypertensive age- and gender-matched controls. All participants completed a 24-h ambulatory electrocardiogram recording and ambulatory BP monitoring (ABPM). Differences in HRV and BPV between the two groups were examined. BPV indices assessed by ABPM included mean systolic BP (SBP), mean diastolic BP (DBP), coefficient of variation and weighted standard deviation of SBP and DBP. ResultsCSVD patients had significant higher 24-h mean systolic BP (SBP), 24-h mean diastolic BP (DBP), daytime mean SBP, nocturnal mean SBP, and nocturnal mean DBP (P < .05 for all). CSVD patients had a significant lower nocturnal SBP fall rate compared with controls (median: 1.0 versus 6.2, respectively; P < .001) and were more likely to be non-dippers and reverse dippers. There were no differences in HRV variables between the two groups. Five logistic models were built to explore the correlations between BPV indices and CSVD. BPV indices were separately entered into the logistic regression models, together with hyperlipidemia, ischemic stroke history, current use of anti-hypertensive agents, and serum blood urea nitrogen. In models 1−3, 24-h mean SBP and nocturnal mean SBP and DBP were significantly correlated with CSVD (r2 = 0.308−0.340). In model 4, the nocturnal SBP fall rate was negatively correlated with CSVD (odds ratio [OR] = 0.871, 95% confidence interval [CI] = 0.804−0.943; P = .001), with r2 = 0.415 fitting the model. In model 5, the pattern of SBP dipping was significantly associated with CSVD, with non-dipper (OR = 8.389, 95%CI = 1.489−47.254; P = .016) and reverse dipper (OR = 27.008, 95%CI = 3.709−196.660; P = .001) having the highest risks of CSVD (r2 = 0.413). ConclusionsLower nocturnal SBP fall rate is associated with CSVD. Non-dipper and reverse dipper hypertensive patients have a higher risk of CSVD.

Abstract 17325: Obesity, Blood Pressure, and Diurnal Variation in Natriuretic Peptides: A Clinical Trial

Background: Obese individuals have disturbed blood pressure (BP) rhythmicity and relative natriuretic peptide (NP) deficiency. The relationship of diurnal variation in NP levels and 24h BP rhythm is not known. Furthermore, mechanisms behind difference in circulating NPs in healthy obese and lean individuals has not been explored. We conducted a prospective clinical trial to evaluate 1) the diurnal rhythmicity of NPs and its relationship with 24-hour BP rhythm between healthy lean and obese individuals, and 2) elucidate mechanism behind NP deficiency in obese. Methods: Healthy, normotensive, lean (BMI:18.5-25 kg/m 2 ) and obese (BMI:30-45 kg/m 2 ) individuals aged 18-40 years, underwent 24-hour standardized inpatient protocol involving ambulatory BP monitoring (ABPM), controlled light intensity, and 10 blood draws, following 5-days of standardized diet. NP gene expression was evaluated in a cohort of 37 healthy donor heart tissues obtained from the MAGNet repository. Results: Among 52 participants screened, a total of 40 participants (18 lean; 22 obese) were enrolled. Diurnal variation in MRproANP levels was seen in both lean and obese individuals (p for rhythmicity=0.001). The mesor of the NP rhythm was 15% (8.5-21.6%) lower in obese. The diurnal variation in MRproANP was in antiphase with diurnal variation of systolic BP (p&lt;0.001) ( Figure ). Obese participants had lower 24h renin levels (p=0.06) and higher nocturnal sodium excretion (p=0.08). Among obese, there was lower expression of NP production genes ( NPPA, NPPB) (p&lt;0.05) , and higher expression of clearance gene ( NPR3 ) (p&lt;0.001) in heart tissue. Conclusions: In a mechanistic human trial, we elucidate key neurohormonal differences in rhythm and evidence of poor salt handling in obese. Decreased production and increased clearance may contribute to the NP deficiency in obese. Targeting the diurnal NP-BP rhythm axis may reduce the cardiovascular risk burden, specifically in obese individuals.

Serum interleukin-18 levels are associated with non-dipping pattern in newly diagnosed hypertensive patients.

Interleukin-18 (IL-18), a pro-inflammatory cytokine, increases inflammation in the endothelium. Increased inflammation plays an important role in the development of hypertension (HT). IL-18 level is higher in hypertensives than normotensives. To investigate the relationship between IL-18 level and diurnal blood pressure (BP) variations in newly diagnosed HT patients. This prospective study included 130 subjects referred to outpatient cardiology clinic with an initial diagnosis of HT. The patients were classified as dipper HT (n = 40), non-dipper HT (n = 50), and normotensive (control, n = 40) according to 24-hour ambulatory BP monitoring. All subjects underwent blood sampling after 12 hours of fasting and transthoracic echocardiography. The serum IL-18 level was significantly higher in the patient group compared with the controls (195.17 ± 93.00 mg/dl vs. 140.75 ± 71.11 mg/dl, P < 0.01) and also in the non-dipper group than in the dipper group (217.3 ± 96.90 mg/dl, 167.5 ± 80.79 mg/dl, P = 0.011). IL-18 level was positively correlated both the night-time SBP and DBP levels (r = 0.29, P = 0.02 and r = 0.34, P < 0.01, respectively). On multivariate linear regression analysis, left atrium diameter, left ventricular mass index, and serum IL-18 level were independent predictors of non-dipping pattern in newly diagnosed HT patients. Higher IL-18 level was particularly associated with an increase in the night-time BP levels. IL-18 can be used as a predictor for non-dipper HT in newly diagnosed HT patients.

Identifying patterns of diurnal blood pressure variation among ELSA-Brasil participants.

Ambulatory blood pressure monitoring (ABPM) is the gold standard method for the diagnosis of hypertension. ABPM provides a set of repeated measurements for blood pressure (BP), usually over 24h. Traditional approaches characterize diurnal BP variation by single ABPM parameters such as average and standard deviation, regardless of the temporal nature of the data. In this way, information about the pattern of diurnal BP variation and relationship between parameters is lost. The objective of this study was to identify and characterize daily BP patterns considering the set of repeated measures from 24-h ABPM. A total of 859 adult participants of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) performed a 24-h ABPM record. Hypertension, sex, age, race/color, education, marital status, smoking, alcohol, physical activity, and BMI were the covariables analyzed. Techniques for longitudinal clustering, multinomial models, and models with mixed effects were used. Three daily BP patterns were identified. Daily BP patterns with high BP presented higher standard deviation and morning surge and lower nocturnal dipping. They showed greater systolic BP variability and faster rise than fall in diastolic BP during sleep. Hypertensive, "pardos," and men had greater odds to present these patterns. Daily BP patterns with high BP presented the worst profile concerning ABPM parameters associated with cardiovascular risk. The daily BP patterns identified contribute to the characterization of diurnal BP variation.

The Effect of Epidermal Growth Factor Inhibition on Diurnal Variation of Blood Pressure in Mice

The Effect of Epidermal Growth Factor Inhibition on Diurnal Variation of Blood Pressure in Mice

Insight into the 24-hour ambulatory central blood pressure in adolescents and young adults.

This study attempted to investigate the behavior of 24-hour central ambulatory blood pressure (ABP) in adolescents and young adults. Adolescents and young adults (age 10-25years) referred for elevated blood pressure (BP) and healthy volunteers had simultaneous 24-hour peripheral (brachial) and central (aortic) ABP monitoring using the same automated upper-arm cuff device (Mobil-O-Graph 24h PWA). Central BP was calculated by the device using two different calibration methods (C1SBP using peripheral systolic (pSBP)/diastolic BP and C2SBP using mean arterial/diastolic BP). A total of 136 participants (age 17.9±4.7years, 54% adolescents, 77% males, 25% volunteers, 34% with elevated peripheral ABP) were analyzed. Twenty-four-hour pSBP was higher than C1SBP, with this difference being more pronounced during daytime than nighttime (16.3±4.5 and 10.5±3.2mmHg, respectively, P<.001). Younger age, higher body height, and male gender were associated with greater systolic ABP amplification (pSBP-C1SBP difference). C1SBP followed the variation pattern of pSBP, yet with smaller nighttime dip (8.4±6.0% vs 11.9±4.6%, P<.001), whereas C2SBP increased (2.4±7.2%) during nighttime sleep (P<.001 for comparison with pSBP change). Older age remained independent determinant of larger nighttime BP fall for pSBP and C1SBP, whereas male gender predicted a larger nighttime C2SBP rise. These data suggest that the calibration method of the BP monitor considerably influences the diurnal variation in central BP, showing a lesser nocturnal dip than pSBP or even nocturnal BP rise, which are determined by the individual's age and gender.

Clinical Implications

Clinical Implications