Time Rate of Blood Pressure Variation Is Associated With Increased Common Carotid Artery Intima-Media Thickness

Association between short-term blood pressure variability and target organ damage in non-dialysis patients with chronic kidney disease

BACKGROUND

It is unclear whether short-term blood pressure variability (BPV) is associated with target organ damage in patients with non-dialysis chronic kidney disease (CKD).

METHODS

A cross-sectional, single-center study was conducted among 3442 non-dialysis CKD patients hospitalized in the department of Nephrology of the Fifth Affiliated Hospital of Sun Yat-sen University from November 2017 to July 2022 and collected the demographic, laboratory, clinic blood pressure, ambulatory blood pressure data, and short-term BPV assessed by the weighted standard deviation (wSD) derived from ambulatory blood pressure monitoring (ABPM). Multivariate logistic analyses were used to evaluate the independent effects between short-term BPV and subclinical target organ damage, including left ventricular hypertrophy (LVH), abnormal carotid intima-media thickness (CIMT), low estimated glomerular filtration rate (eGFR), and albuminuria.

RESULTS

The average age of the participants was 47.53 ± 14.06 years and 56% of participants were male. The baseline eGFR was 69 mL/min/1.73 m2. Based on the tertile distribution of wSD according to equal numbers, patients were divided into three categories with T1(< 9.66 mmHg), T2(9.66-12.23 mmHg), and T3(> 12.23 mmHg) of SBPV; T1(< 8.17 mmHg), T2(8.17-9.93 mmHg), and T3(> 9.93 mmHg) of DBPV. The participants with the higher wSD group had a higher prevalence of target organ damage than their counterparts (P-trend < 0.05). An increasing trend in short-term variability was present with advancing CKD stages (P-trend < 0.001). Multivariate logistic analyses results showed that the odds ratio (OR) of SBP wSD was (1.07 [1.03,1.11], P < 0.001) for LVH, (1.04 [1.01,1.07, P = 0.029) for abnormal CIMT, (1.05 [1.02,1.08], P = 0.002) for low eGFR, and (1.06 [1.02,1.09], P = 0.002) for albuminuria; The OR of DBP wSD was (1.07 [1.02,1.12], P = 0.005) for LVH, (1.05 [1.01,1.09], P = 0.028) for abnormal CIMT, (1.05 [1.01,1.09], P = 0.022) for low eGFR, and (1.05 [1.01,1.10], P = 0.025) for albuminuria when adjusted for confounding factors and mean BP.

CONCLUSIONS

In conclusion, short-term BPV is associated with target organ damage, and irresponsible of average blood pressure levels, in Chinese non-dialysis CKD participants.

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

PURPOSE

Non-invasive, beat-to-beat variations in physiological indices provide an opportunity for more accessible assessment of autonomic dysfunction. The potential association between the changes in these parameters and arterial stiffness in hypertension remains poorly understood. This systematic review aims to investigate the association between non-invasive indicators of autonomic function based on beat-to-beat cardiovascular signals with arterial stiffness in individuals with hypertension.

METHODS

Four electronic databases were searched from inception to June 2022. Studies that investigated non-invasive parameters of arterial stiffness and autonomic function using beat-to-beat cardiovascular signals over a period of > 5min were included. Study quality was assessed using the STROBE criteria. Two authors screened the titles, abstracts, and full texts independently.

RESULTS

Nineteen studies met the inclusion criteria. A comprehensive overview of experimental design for assessing autonomic function in terms of baroreflex sensitivity and beat-to-beat cardiovascular variabilities, as well as arterial stiffness, was presented. Alterations in non-invasive indicators of autonomic function, which included baroreflex sensitivity, beat-to-beat cardiovascular variabilities and hemodynamic changes in response to autonomic challenges, as well as arterial stiffness, were identified in individuals with hypertension. A mixed result was found in terms of the association between non-invasive quantitative autonomic indices and arterial stiffness in hypertensive individuals. Nine out of 12 studies which quantified baroreflex sensitivity revealed a significant association with arterial stiffness parameters. Three studies estimated beat-to-beat heart rate variability and only one study reported a significant relationship with arterial stiffness indices. Three out of five studies which studied beat-to-beat blood pressure variability showed a significant association with arterial structural changes. One study revealed that hemodynamic changes in response to autonomic challenges were significantly correlated with arterial stiffness parameters.

CONCLUSIONS

The current review demonstrated alteration in autonomic function, which encompasses both the sympathetic and parasympathetic modulation of sinus node function and vasomotor tone (derived from beat-to-beat cardiovascular signals) in hypertension, and a significant association between some of these parameters with arterial stiffness. By employing non-invasive measurements to monitor changes in autonomic function and arterial remodeling in individuals with hypertension, we would be able to enhance our ability to identify individuals at high risk of cardiovascular disease. Understanding the intricate relationships among these cardiovascular variability measures and arterial stiffness could contribute toward better individualized treatment for hypertension in the future.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO ID: CRD42022336703. Date of registration: 12/06/2022.

Effects of chlorthalidone plus amiloride compared with amlodipine on short-term blood pressure variability in individuals with hypertension and obstructive sleep apnea: a randomized controlled trial

OBJECTIVE

To compare the effects of chlortalidone plus amiloride and amlodipine on blood pressure (BP) variability in patients with hypertension and obstructive sleep apnea syndrome (OSA).

METHODS

A randomized, controlled, double-blind trial enrolled men and women aged 40 years or older with a diagnosis of OSA (apnea-hypopnea index 10-40 apneas/h of sleep) confirmed by overnight laboratory polysomnography and systolic BP 140-159 mmHg or diastolic BP 90-99 mmHg. Participants were randomized to receive chlortalidone 25 mg plus amiloride 5 mg daily or amlodipine 10 mg daily for 8 weeks. BP variability was calculated from 24-hour ambulatory BP monitoring at baseline and follow-up using the following indices: SD, coefficient of variation, average real variability (ARV), time-rate index, and variability independent of the mean (VIM).

RESULTS

The study included 65 patients, with 33 assigned to the chlortalidone plus amiloride group and 32 to the amlodipine group. Participants in both groups had similar baseline characteristics. Short-term BP variability decreased within groups for SD and ARV indexes for 24-hour systolic BP and daytime systolic BP, but statistically significant time*group interactions were found for sleep systolic SD and VIM, with greater reduction in patients treated with amlodipine.

CONCLUSION

In brief, our study has shown that the use of chlorthalidone in combination with amiloride and amlodipine produces comparable effects on short-term BP variability in patients with hypertension and OSA. Therefore, our findings suggest that BP variability may not be a significant factor when choosing between these medications for the treatment of hypertension and OSA.

Analysis of Mechanisms for Increased Blood Pressure Variability in Rats Continuously Infused with Angiotensin II

Objective

We reported that rats infused with angiotensin II (Ang II) are not only a model of hypertension but also of augmented 24 h blood pressure variability (BPV). In this study, we examined the mechanisms for Ang II-induced BPV, focusing on BP, heart rate (HR), baroreceptor reflex sensitivity (BRS), and medial area of the aortic arch.

Methods

Nine-week-old male Wistar rats were infused with subcutaneous 5.2 μg/kg/h Ang II with or without oral administration with 30 mg/kg/day azelnidipine for 14 days. BP and HR were recorded every 15 min under an unrestrained condition by a radiotelemetry system, while BPV was evaluated by standard deviation of BP. BRS was quantified by a sequence analysis, and medial thickness of the aortic arch was measured by microscopic examination.

Results

BPV increased at days 7 and 14 following continuous infusion of Ang II. Before the infusion, a positive correlation was found between BP and HR, but it became negative at day 7 and then weakened or disappeared at day 14. BRS was slightly impaired at day 7 and significantly lowered at day 14, a phenomenon accompanied by thickened medial area of the aortic arch in Ang II-infused rats. Those Ang II-induced alterations were all significantly attenuated by azelnidipine.

Conclusions

The present findings suggest sequential changes in the mechanisms behind augmented BPV in rats continuously infused with Ang II over 14 days.

Blood pressure variability in children with obesity and sleep-disordered breathing following positive airway pressure treatment

Obese youth with sleep-disordered breathing are treated with positive airway pressure to improve sleep and cardiovascular status. While improvements in sleep parameters have been confirmed, a study by Katz et al. showed no major improvement in ambulatory blood pressure. The aim of this ancillary study was to analyze short-term blood pressure variability, following positive airway pressure treatment, as a more sensitive marker of cardiovascular health. We analyzed 24-h blood pressure variability data in 17 children, taken at baseline and after 12 months of treatment. These data were derived from an already published prospective, multicenter cohort study conducted in 27 youth (8-16 years) with obesity who were prescribed 1-year of positive airway pressure for moderate-severe sleep-disordered breathing. Significant decreases were found in 24 h systolic blood pressure (p = 0.040) and nighttime diastolic blood pressure (p = 0.041) average real variability, and diastolic blood pressure (p = 0.035) weighted standard deviation. Significant decreases were noted in nighttime diastolic blood pressure time rate variability (p = 0.007). Positive airway pressure treatment resulted in a significant decrease in blood pressure variability, suggesting a clinically significant improvement of sympathetic nerve activity in youth with obesity and sleep-disordered breathing. IMPACT: Cardiovascular variability, as measured by blood pressure variability, is improved in children following positive airway pressure treatment. Our novel findings of improved blood pressure time rate variability are the first described in the pediatric literature. Future studies aimed at analyzing target organ damage in this patient population will allow for a better understanding as to whether alterations in blood pressure variability translate to decreasing target organ damage in children, as seen in adults.

Sampling rate influences measures of blood pressure variability in ambulatory blood pressure monitoring

BACKGROUND

Ambulatory blood pressure monitoring (ABPM) is a valuable tool in the diagnosis and management of hypertension and it is a good predictor of future cardiovascular events. Lack of normal threshold values of ABPM parameters and inconsistency in the sampling rate of recording are hurdles in its wider usage. The aim of the present investigation was to study the influence of sampling rate on ABPM.

METHODS

ABPM was performed in 47 healthy subjects and the effect of different sampling rates was studied on ABPM parameters.

RESULTS

When data were down-sampled, there was a trend towards decreased concordance and increased dispersion with less frequent recordings. Percent dispersion of MESOR, 24-h average, 24 h standard deviation (SD), awake hours average and sleep hours average of systolic BP (SBP) were around 10% for a sampling interval of 1 h. While average real variability (ARV), morning surge and percent dip in SBP exhibited more than 30% dispersion at a sampling interval of 30 min.

CONCLUSION

24-h average blood pressure (BP) is less sensitive to sampling rate whereas BP variability parameters such as ARV, morning surge and percent dip in SBP are highly sensitive. We suggest that for improving the accuracy of BP variability parameters, a higher sampling rate is desirable around the time of awakening (~2 h before and after the expected time of awakening). At other times, a lower sampling rate may be used for maximizing patient comfort without compromising measurement accuracy.

Effect of blood pressure variability in the randomized controlled BP TARGET trial

BACKGROUND AND PURPOSE

The Blood Pressure Target in Acute Ischemic Stroke to Reduce Hemorrhage After Endovascular Therapy (BP TARGET) trial evaluated whether an intensive systolic blood pressure (SBP) target resulted in reduced rates of intracranial hemorrhage (ICH) after successful endovascular therapy (EVT) but did not assess the effect of blood pressure variability (BPV) on functional outcomes and ICH occurrence. We sought to evaluate this question in the BP TARGET trial.

METHODS

We performed a post hoc analysis of the BP TARGET trial and included patients with at least 50% of blood pressure (BP) recordings during the first 24 h after EVT. BPV parameters were SBP and diastolic BP (DBP) coefficient of variation (CV), standard deviation (SD), maximum-minimum (max-min), successive variation (SV), and time rate. The primary outcome was favorable functional outcome (3-month modified Rankin Scale between 0 and 2); the secondary outcome was the rate of ICH at 24 h.

RESULTS

We included 290 patients (mean number of BP measures = 30.4, SD = 8.0). BPV parameters (SBP_SD , SBP_max-min , SBP_CV ) were higher in the intensive SBP target group. Only DBP BPV parameters were associated with worse functional outcomes in the unadjusted model (DBP_SD , DBP_max-min , DBP_CV , and DBP_SV ), but not after adjustment. Higher SBP_max-min was associated with worse functional outcomes in Thrombolysis in Cerebral Infarction 2B patients (odds ratio [OR] = 0.62, 95% confidence interval [CI] = 0.38-1.02), but not in patients with complete reperfusion (OR = 1.27, 95% CI = 0.80-2.02, p for heterogeneity (p_het =0.037). None of the BPV parameters was associated with ICH, regardless of the randomization group or the reperfusion grade.

CONCLUSIONS

BPV was significantly higher in the intensive SBP target group but was not associated with functional outcome or ICH.

Trajectory patterns of blood pressure change up to six years and the risk of dementia: a nationwide cohort study

The present study aimed to investigate the associations between the trajectory of blood pressure (BP) change and the risk of subsequent dementia and to explore the differences in age, gender, and hypertension subgroups. We included 10,660 participants aged ≥ 60 years from 1998 to 2018 waves of the Chinese Longitudinal Healthy Longevity Survey. Latent growth mixture models were used to estimate BP trajectories. Cox-proportional hazard models were used to analyze the effects of BP trajectories on the risk of dementia. According to the results, stabilized systolic BP (SBP) was found to be associated with a higher risk of dementia compared with normal SBP [adjusted hazard ratio (aHR): 1.62; 95% confidence interval (CI): 1.27-2.07] and elevated SBP (aHR: 2.22; 95% CI: 1.51-3.28) in and only in the subgroups of the oldest-old, women, and subjects without hypertension at baseline. Similarly, stabilized pulse pressure (PP) was associated with a higher risk of dementia compared with normal PP (aHR: 1.52; 95% CI: 1.24-1.88) and elevated PP (aHR: 2.12; 95% CI: 1.48-3.04) in and only in the subgroups of the oldest-old, women, and subjects with hypertension at baseline. These findings suggest that stabilized SBP and PP have predictive significance for the occurrence of dementia in late life, and the factors of age, gender, and late-life hypertension should be considered when estimating the risk of BP decline on dementia.

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

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.

Effect of visit-to-visit blood pressure variability on cardiovascular events in populations with different body mass indexes: a prospective cohort study

OBJECTIVE

This study was performed to explore the effects of visit-to-visit blood pressure variability (BPV) on cardiovascular events (CVEs) in people with various body mass indexes (BMIs).

DESIGN

Prospective cohort study.

SETTING

The average real variability of systolic blood pressure (ARV_SBP) was the indicator for visit-to-visit BPV. The participants were divided into three groups: normal weight, overweight and obesity. We further divided these groups into four subgroups based on the ARV_SBP. A Cox regression model was used to calculate the HRs of the ARV_SBP on CVEs in the same and different BMI groups. Additionally, a competitive risk model was used to calculate the HRs of the ARV_SBP on CVEs in the same BMI group.

PARTICIPANTS

In total, 41 043 individuals met the inclusion criteria (no historical CVEs or tumours, no incidence of CVEs or tumours and no death during the four examinations) and had complete systolic blood pressure and BMI data.

RESULTS

A total of 868 CVEs occurred. The cumulative incidence of CVEs increased as ARV_SBP rose in both the normal weight and overweight groups. In same BMI groups, the risk of CVEs significantly increased as ARV_SBP increased only in the normal weight group (highest quartiles of ARV_SBP: HR (95% CI) 2.20 (1.46-3.31)). In the different BMI groups, the risk of CVEs in the ARV_SBP subgroup in each BMI group was higher than that the least quintile of ARV_SBP in the normal weight group (highest quartiles of ARV_SBP in obesity: HR (95% CI) 2.28 (1.47-3.55)). The result of the competitive risk model did not change.

CONCLUSIONS

As BMI and ARV_SBP increase, the risk of CVEs increases. However, the risk of visit-to-visit BPV on CVEs varies in different BMI groups, especially in people of normal weight.

TRIAL REGISTRATION NUMBER

CHiCTR-TNC1100 1489.

Blood Pressure Variability and Severity of Early Prognosis in Patients with Acute Pontine Infarction

Background

Increased blood pressure (BP) variability may worsen the prognosis of stroke. This study aimed at investigating the association between BP variability and early functional prognosis in patients with pontine infarction.

Methods

According to types of pontine infarction, all the 137 patients were divided into two groups: 70 patients with paramedian pontine infarction (PPI) and 67 patients with deep pontine infarction (DPI). Common risk factors, 24-hour continuous blood pressure monitoring data, and the coefficient of variation were collected after admission in the hospital. Functional outcomes were evaluated with modified Rankin scale (mRS) at 3 months after discharge (favorable outcome: mRS scores ≤ 2; poor outcome: mRS scores > 2).

Results

The level of Glu, HbA1c, LDL, and NIHSS scores in the PPI group was significantly higher than that in the DPI group, and the concentration of blood uric acid was lower in the PPI group. Diastolic pressure in the PPI group is significantly higher than that in the DPI group, and coefficient of variation (CV) of systolic pressure in PPI is higher when compared with DPI ((88.77 ± 1.71) mmHg vs. (80.74 ± 1.31) mmHg; (11.54 ± 0.35) vs. (10.24 ± 0.25)). In multivariate analyses, the CV of systolic pressure, diastolic pressure, NIHSS scores, and the paramedian pontine infarction was independently associated with 3-month clinical outcome (OR = 1.94, 95% CI = 1.252–2.994, P=0.003; OR = 1.08, 95% CI = 1.002–1.166, P=0.04; OR = 1.58, 95% CI = 1.164–2.159, P=0.003; OR = 9.87, 95% CI = 1.045–32.193, P=0.04).

Conclusion

In conclusion, increased 24-hour (BP) variability, NIHSS scores, and paramedian pontine were associated with early poor prognosis in patients with acute pontine infarction.

The association between morning blood pressure and subclinical target organ damage in the normotensive population

OBJECTIVE

To investigate whether isolatedly elevated morning blood pressure (BP) is associated with subclinical target organ damage in normotensive individuals.

METHODS

In all, 287 normotensive individuals were included in this cross-sectional study. Each participant underwent anthropometric measurements, serum biochemistry evaluation, 24-h ambulatory BP monitoring, echocardiography, and carotid ultrasonography. The morning BP and morning surge were defined as: the average BP within 2 h after waking up, and the difference between the mean systolic BP (SBP) within 2 h after waking up and the mean SBP during the hour that included the lowest BP reading during sleep, respectively.

RESULTS

The prevalence of elevated morning BP was 37.3%. Individuals with elevated morning BP had higher left ventricular mass index and morning surge, and also mean 24-h, daytime, and night-time SBP and diastolic BP, BP variability (all P < 0.05). Left ventricular mass index was correlated with 24-h, daytime, night-time, and morning SBP, and morning surge (Pearson's correlation coefficients: 0.271, 0.262, 0.215, 0.368, and 0.415, respectively; all P < 0.05); and standard deviations of 24-h, daytime, and night-time SBP (Pearson's correlation coefficient: 0.303, 0.234, and 0.309, respectively), and coefficient of variations of 24-h and night-time SBP (Pearson's correlation coefficients: 0.253 and 0.271, respectively). Morning surge had the strongest correlation with left ventricular mass index in multiple regression analysis. Only daytime and morning SBP could discriminate elevated morning surge (≥35 mmHg), with an area under the curve of 0.744 and 0.864, respectively (both P < 0.01), and an optimal threshold of 121.5 mmHg for morning SBP.

CONCLUSION

Our findings suggest that isolated elevation of morning BP in normotensive individuals is associated with left ventricular hypertrophy. Home monitoring of morning BP may be suitable for detecting abnormal morning surge.

The cumulative blood pressure load and target organ damage in patients with essential hypertension

The area under the blood pressure curve is associated with target organ damage, but accurately estimating its value is challenging. This study aimed to improve the utility of the area under the blood pressure curve to predict hypertensive target organ damage. This retrospective cohort study comprised of 634 consecutive patients with essential hypertension for >1 year. Target organ damage was defined as the presence of left ventricular hypertrophy and/or carotid artery plaques. We evaluated the associations between the cumulative blood pressure load, which was derived from ambulatory blood pressure monitoring data, and target organ damage. The predictive value of the cumulative blood pressure load for target organ damage was assessed using receiver operating characteristic curves. Left ventricular hypertrophy and carotid artery plaques were present in 392 (61.8%) and 316 (49.8%) patients, respectively. Patients with left ventricular hypertrophy and/or carotid artery plaques had higher 24‐hour blood pressure, nocturnal cumulative systolic blood pressure, and nocturnal cumulative pulse pressure load. The nocturnal cumulative systolic blood pressure load was an independent predictor of left ventricular hypertrophy (odds ratio = 1.002, 95% confidence interval: 1.001‐1.004; P = .000) and carotid artery plaques (odds ratio = 1.003, 95% confidence interval: 1.002‐1.007; P = .007). The nocturnal cumulative systolic blood pressure and cumulative pulse pressure load, relative to mean blood pressure, were superior in predicting hypertensive target organ damage. Hence, the cumulative blood pressure load is a better indicator of blood pressure consequences, and the nocturnal cumulative systolic blood pressure and cumulative pulse pressure loads could predict target organ damage.

Blood Pressure Variability and the Risk of Dementia: A Nationwide Cohort Study

To investigate the association between visit-to-visit variability in blood pressure and the incidence of dementia and its subtypes in a general population, we conducted a population-based retrospective cohort study using the Korean National Health Insurance System database. We identified 7 844 814 subjects without a history of any dementia who underwent ≥3 health examinations from 2005 to 2012 in the Korean National Health Insurance System cohort. Blood pressure variability (BPV) was measured using the variability independent of the mean, coefficient of variation, and SD. During the median follow-up of 6.2 years, there were 200 574 cases of all-cause dementia (2.8%), 165 112 cases of Alzheimer's disease (2.1%), and 27 443 cases of vascular dementia (0.3%). There was a linear association between higher BPV and outcome measures. In the multivariable adjusted model, the hazard ratios and 95% CIs of all-cause dementia were 1.06 (1.04-1.07) for the highest quartile of variability independent of the mean of diastolic blood pressure only, 1.09 (1.08-1.11) for that of systolic blood pressure only, and 1.18 (1.16-1.19) for that of both systolic and diastolic blood pressure compared with subjects having no highest quartile for BPV. Consistent results were noted for Alzheimer's disease and vascular dementia using other indices of variability and in various sensitivity and subgroup analyses. BPV is an independent predictor for developing dementia and its subtypes. A dose-response relationship was noted between higher BPV and dementia incidence. Reducing BPV may be a target for preventing dementia in the general population.

Blood Pressure Variability in Pregnancy: an Opportunity to Develop Improved Prognostic and Risk Assessment Tools

PURPOSE OF REVIEW

This review discusses the mortality and morbidity of hypertensive disorders of pregnancy (HDP) and the current diagnostic thresholds. It then explores measurement of variability in blood pressure (BP) during pregnancy as an opportunity to identify women at high risk of cardiovascular disease (CVD) later in life.

RECENT FINDINGS

HDP is known to be associated with increased risk of long-term CVD. Current CVD prognostic tools do not incorporate a history of HDP given a lack of improved risk discrimination. However, HDP diagnostic criteria are currently based on a binary threshold, and there is some evidence for the use of variability in BP throughout gestation as a marker of CVD risk. HDP increases long-term risk of CVD. Future studies investigating changes in diagnostic criteria, including the use of BP variability, may improve long-term CVD risk prediction and be incorporated into future risk assessment tools.

Effects of doxazosin mesylate versus nifedipine on blood pressure variability in hypertensive patients: a randomized crossover study (SIMILAR)

OBJECTIVE

Blood pressure variability (BPV) is a powerful predictor of end-organ damage, cardiovascular events and mortality independently of the BP level. Calcium channel blockers may offer an advantage over other first-line antihypertensive drugs by preventing increased BPV. But the effect of alpha-receptor blockers on BPV in hypertensive patients is still unclear.

METHODS

In this crossover trial, 36 hypertensive patients were randomly assigned to two groups, receiving doxazosin mesylate gastrointestinal therapeutic system (GITS) (4 mg/day) or nifedipine GITS (30 mg/day) for 12 weeks, followed by a 2-week washout period then a 12-week crossover phase. At baseline and after 12-week treatment, 24-hour ambulatory BP monitoring was performed. BPV was evaluated through standard deviation (SD), coefficient of variation (CV), and average real variability (ARV) of systolic BP (SBP) and diastolic BP (DBP) during daytime, nighttime and over 24 hours.

RESULTS

After 12-week treatment, both doxazosin and nifedipine significantly decreased SBP and DBP (P < 0.05), whereas no between-group differences were shown (P>0.05). Systolic BPV (24-hour SD, CV, and ARV; daytime SD; nighttime SD and CV) and diastolic BPV (24-hour SD and ARV) were significantly lowered by nifedipine (P < 0.05); doxazosin resulted in significant reductions of systolic BPV (24-hour SD, CV and ARV; daytime SD; nighttime SD) and diastolic BPV (nighttime SD and CV) (P < 0.05). Doxazosin was revealed to be as effective as nifedipine for reducing BPV (P > 0.05) except for 24-hour SBP ARV.

CONCLUSIONS

Doxazosin mesylate GITS had similar therapeutic effects on BP, BP SD, and BP CV lowering as nifedipine GITS in patients with mild-to-moderate essential hypertension.

Blood pressure variability and hemorrhagic transformation in patients with successful recanalization after endovascular recanalization therapy: A retrospective observational study

OBJECTIVE

Although blood pressure (BP) variability has been regarded as a risk factor for hemorrhagic transformation (HTF) after intravenous thrombolysis, its effect on HTF after endovascular recanalization therapy (ERT) remains to be elucidated. We aimed to study the relationship between BP variability and symptomatic intracerebral hemorrhage (sICH) after successful recanalization with ERT.

METHODS

A total of 211 patients with acute ischemic stroke and successful recanalization (thrombolysis in cerebral infarction 2b or 3) after ERT were included between January 2013 and May 2017. The BP data following ERT was obtained over the first 24 hours using parameters including mean, maximum, minimum, difference between maximum and minimum, standard deviation, coefficient of variation, successive variations, and time rate (TR) of BP variation for systolic BP (SBP) and diastolic BP. sICH was defined as parenchymal hemorrhage type 2 with neurological deterioration of 4 points of more on the National Institute of Health Stroke Scale.

RESULTS

Among the included patients, 20 (9.5%) developed sICH after successful ERT. The parameters linked with BP fluctuation over time were significantly related to sICH. After adjusting for confounders, the TR of SBP (per 0.1 mmHg/min increase) variation was independently associated with sICH (odds ratio = 1.71, 95% confidence interval = 1.013-2.886).

INTERPRETATION

Time-related BP variability in the first 24 hours following successful ERT was more correlated with sICH than other absolute BP levels. This suggests that maintaining a stable BP may be an important factor in preventing sICH after successful ERT. Ann Neurol 2019;85:574-581.

Dynamic cerebral autoregulation measurement using rapid changes in head positioning: experiences in acute ischemic stroke and healthy control populations

The ideal technique for dynamic cerebral autoregulation (dCA) assessment in critically ill patients should provide considerable variability in blood pressure (BP) but without the need for patient cooperation. We proposed using rapid head positioning (RHP) over spontaneous BP fluctuations for dCA assessment in patients with acute ischemic stroke (AIS). Cerebral blood velocity (transcranial Doppler), beat-to-beat BP (Finometer), and end-tidal CO2 (capnography) were recorded during 5-min baseline and RHP in 16 controls (8 women and 8 men, mean age: 57 ± 16 yr) and 15 patients with AIS (7 women and 8 men, mean age: 69 ± 8 yr) at two (12 ± 8 days) and three visits (13.3 ± 6.9 h, 4.8 ± 3.2 days, and 93.9 ± 11.5 days from the symptom onset), respectively. All participants were able to complete the RHP protocol without difficulty. Compared with controls, patients with AIS were hypocapnic (all visits, P < 0.0024) and hypertensive ( visit 1, P = 0.011), although BP gradually reduced after the acute phase. RHP demonstrated greater beat-to-beat BP variability (BPV) in controls ( visits 1 and 2, P < 0.001) but not in patients with AIS at any visit. Compared with controls, a reduced autoregulation index (ARI) was demonstrated in patients with AIS, at visit 2 for the baseline recording but not at other visits or during RHP. The area under the receiver-operating curve was 0.53 and 0.54 for baseline and RHP, respectively. The RHP paradigm required minimal patient cooperation and could be considered a feasible alternative for assessing dCA, mainly in conditions leading to increased BPV. The lack of BPV increase in AIS with RHP deserves further investigation.

NEW & NOTEWORTHY This study used rapid head positioning (RHP) to enhance blood pressure (BP) variability (BPV) to improve BP signal-to-noise ratio and reliability of dynamic cerebral autoregulation (dCA). RHP was well accepted by controls and acute ischemic stroke (AIS); the increased BPV induced in controls was not observed in AIS, suggesting BPV at rest was already elevated. RHP did not improve detection of impaired CA in AIS; further work is needed to understand the different responses observed.

Morning surge in blood pressure and blood pressure variability in Asia: Evidence and statement from the HOPE Asia Network

Hypertension is a major risk factor for cardiovascular and cerebrovascular diseases. To effectively prevent end-organ damage, maintain vascular integrity and reduce morbidity and mortality, it is essential to decrease and adequately control blood pressure (BP) throughout each 24-hour period. Exaggerated early morning BP surge (EMBS) is one component of BP variability (BPV), and has been associated with an increased risk of stroke and cardiovascular events, independently of 24-hour average BP. BPV includes circadian, short-term and long-term components, and can best be documented using out-of-office techniques such as ambulatory and/or home BP monitoring. There is a large body of evidence linking both BPV and EMBS with increased rates of adverse cardio- and cerebrovascular events, and end-organ damage. Differences in hypertension and related cardiovascular disease rates have been reported between Western and Asian populations, including a higher rate of stroke, higher prevalence of metabolic syndrome, greater salt sensitivity and more common high morning and nocturnal BP readings in Asians. This highlights a need for BP management strategies that take into account ethnic differences. In general, long-acting antihypertensives that control BP throughout the 24-hour period are preferred; amlodipine and telmisartan have been shown to control EMBS more effectively than valsartan. Home and ambulatory BP monitoring should form an essential part of hypertension management, with individualized pharmacotherapy to achieve optimal 24-hour BP control particularly the EMBS and provide the best cardio- and cerebrovascular protection. Future research should facilitate better understanding of BPV, allowing optimization of strategies for the detection and treatment of hypertension to reduce adverse outcomes.

C-reactive protein and blood pressure variability in type 2 hypertensive diabetic patients

OBJECTIVE

Increased blood pressure (BP) variability and inflammation are included among the factors recognized as potential predictors of cardiovascular events in type 2 diabetes and hypertension. This study aimed to evaluate whether C-reactive protein (CRP) is associated with increased BP variability in diabetic-hypertensive patients.

PATIENTS AND METHODS

We carried out a cross-sectional study with 285 diabetic-hypertensive patients, evaluating laboratory characteristics and 24-h ambulatory BP monitoring. SD, coefficient of variation (CV%), time-rate index of 24-h systolic BP (SBP), and 24-h BP patterns were evaluated. Pearson's χ-test, Student's t-test, and the Mann-Whitney test were used to compare the groups. Groups were defined by CRP of up to 3 mg/l (low) and more than 3 mg/l (high).

RESULTS

The age of the patients was 59 (54-62) years; 101 (35%) were men. There was an increase in office SBP [137 (127-148) vs. 145 (130-157) mmHg] and DBP [79 (73-86) vs. 82 (76-91) mmHg] in the high CRP group. Blood pressure variability indexes were not different among groups [SD: 11.2 (9-15) vs. 12.2 (10-15) mmHg; CV%: 8.6 (7-11) vs. 9.4 (7-12); time rate: 0.55±0.12 vs.12.2 (10-15) mmHg/min]. In addition, BMI (29.3±3.8 vs. 30.9±3.6 kg/m), total cholesterol [166 (148-190) vs. 177 (156-210) mg/dl], and HbA1c [7.5% (6.6-8.9) vs.8.3% (7.1-9.9)] were higher in the high CRP group.

CONCLUSION

In patients with diabetes and hypertension, higher CRP levels are linked to cardiometabolic derangements, although they are not associated with increased BP variability.

Comparative analysis of several methods for blood pressure measurement in the morning in patients with arterial hypertension

Aim. To compare the known methods of blood pressure (BP) measurement in the morning and a new method for estimating the average morning BP for fixed time intervals, comparing their reproducibility and validity.

Material and methods. We analyzed database containing 983 cases of ambulatory blood pressure monitoring (ABPM). Results of ABMP in patients with hypertension without severe associated diseases and weekly cancellation of antihypertensive therapy were analyzed. Blood pressure data per 24-hour period, day and night, level and rate of morning BP surge were assessed. In addition, we proposed new method for estimating the average morning BP level for fixed time intervals, based on calculating the average BP level for the following time windows: from 5:00 to 7:00 a.m., from 7:00 to 9:00 a.m., from 9:00 to 11:00 a.m. To assess the reproducibility of the new method, we determined correlations between the first and second group results calculated by the new method based on two repeated ABPM conducted with 1-2 weeks interval (n=90). To study the validity of the new method for measurement of average morning BP level, we used an objective validation criterion — Left Ventricular Myocardium Mass Index (LVMMI). There were performed 98 echocardiographic tests with the use of Acuson 128XP. LVMMI was calculated using the L. Teichholtz method (1976).

Results. The new method for measurement of average morning BP level had good reproducibility while the reproducibility of dynamic showings of ABMP (level and rate of morning BP surge) was low. A new method for assessing morning blood pressure was characterized by a high level of validity: the indicators obtained using this technique reliably correlated with the validation criteria: LVMI and the average daily blood pressure level.

Conclusion. The proposed new method for estimating the average morning level of blood pressure has a high level of validity and reproducibility. Time interval from 7 to 9 a. m. seems to be the most optimal. The maximum reproducibility of the showings was noted during this period.

Impact of body mass index on long-term blood pressure variability: a cross-sectional study in a cohort of Chinese adults

BACKGROUND

Obesity and overweight are related to changes in blood pressure, but existing research has mainly focused on the impact of body mass index (BMI) on short-term blood pressure variability (BPV). The study aimed to examine the impact of BMI on long-term BPV.

METHODS

Participants in the Kailuan study who attended all five annual physical examinations in 2006, 2008, 2010, 2012, and 2014 were selected as observation subjects. In total, 32,482 cases were included in the statistical analysis. According to the definition of obesity in China, BMI was divided into four groups: underweight (BMI < 18.5 kg/m²), normal weight (18.5 ≤ BMI < 24.0 kg/m²), overweight (24.0 ≤ BMI < 28.0 kg/m²), and obese (BMI ≥ 28.0 kg/m²). We used average real variability to evaluate long-term systolic BPV. The average real variability of systolic blood pressure (ARV_SBP) was calculated as (|sbp2 - sbp1| + |sbp3 - sbp2 | + |sbp4 - sbp3| + |sbp5 - sbp4|)/4. Differences in ARV_SBP by BMI group were analyzed using analysis of variance. Stepwise multivariate linear regression and multiple logistic regression analyses were used to assess the impact of BMI on ARV_SBP.

RESULTS

Participants' average age was 46.6 ± 11.3 years, 24,502 were men, and 7980 were women. As BMI increases, the mean value of ARVSBP gradually increases. After adjusting for other confounding factors, stepwise multivariate linear regression analysis showed that ARVSBP increased by 0.077 for every one-unit increase in BMI. Multiple logistic regression analysis indicated that being obese or overweight, compared with being normal-weight, were risk factors for an increase in ARVSBP. The corresponding odds ratios of being obese or overweight were 1.23 (1.15-1.37) and 1.10 (1.04-1.15), respectively.

CONCLUSIONS

There was a positive correlation between BMI and ARVSBP, with ARVSBP increasing with a rise in BMI. BMI is a risk factor for an increase in ARVSBP.

TRIAL REGISTRATION

Registration No.: CHiCTR-TNC1100 1489 ; Registration Date: June 01, 2006.

Early Vascular Aging Risk Assessment From Ambulatory Blood Pressure Monitoring: The Early Vascular Aging Ambulatory Score

BACKGROUND

This study compared the diagnostic accuracy of blood pressure (BP) measurement methods, office BP, ambulatory BP monitoring (ABPM), and home BP, in the identification of early vascular aging (EVA) and developed a score to predict the risk of EVA in hypertensive patients.

METHODS

Two-hundred eighty-two consecutive subjects (39.7% male) aged 56.8  ±  15.8 years were included. Office and out-of-office BP measurements including ABPM on a usual working day and 7 days home BP monitoring were performed. Carotid-femoral pulse wave velocity (c-f PWV) was measured in all patients. EVA was defined as c-f PWV values higher than the expected for age average values according to European population data.

RESULTS

In univariate analysis, EVA was significantly correlated with office systolic BP, average 24-hour systolic and diastolic BP, and average 24-hour and office heart rates. The area under the curve for predicting EVA was 0.624 (95% CI 0.551 to 0.697), 0.559 (95% CI 0.484 to 0.635) and 0.565 (95% CI 0.49 to 0.641), for daytime, home, and office systolic BP, respectively. Ambulatory BP variables, age, sex, body mass index, diabetes mellitus (yes/no), and estimated glomerular filtration rate were used to develop a new score for EVA providing a total accuracy of 0.82, 0.84 sensitivity, and 0.78 specificity.

CONCLUSIONS

In conclusion, the new risk score, Early Vascular Aging Ambulatory score, may accurately identify hypertensive patients with EVA using ABPM values and classic cardiovascular risk factors.

Impact of treatment with glibenclamide or vildagliptin on glucose variability after aerobic exercise in type 2 diabetes: A randomized controlled trial

AIMS

To evaluate the glucose variability, oxidative stress, metabolic and cardiovascular responses after an aerobic exercise session in diabetic patients on treatment with metformin plus vildagliptin or glibenclamide.

METHODS

Parallel clinical trial including patients with type 2 diabetes treated with metformin plus vildagliptin or glibenclamide for 12 weeks. Glucose variability, oxidative stress, metabolic (plasma glucose, insulin and glucagon-like-peptide-1) and cardiovascular responses were evaluated at rest, during and after a 30 min aerobic exercise session (70% of the peak heart rate).

RESULTS

Thirteen patients were included, seven in vildagliptin group (METV) and six in glibenclamide group (METG), baseline glycated hemoglobin (HbA1c) 8.8 ± 0.3%. Treatment reduced HbA1c (1.2% and 1.5% for METV and METG, respectively). The aerobic exercise session did not change glucose variability in both groups. A decrease in glucose during exercise recovery was found, with area under the curve lower in the METG vs. METV (p = 0.04). After the intervention, systolic blood pressure (SBP) decreased in both groups. Patients treated with vildagliptin showed lower SBP variability compared to those treated with glibenclamide.

CONCLUSIONS

Besides improvement in glucose control and reduction of SBP obtained by both treatments, lower blood pressure variability was observed in patients receiving vildagliptin. Glucose variability remained unaffected by both interventions and the exercise session.

Blood pressure variability estimated by ARV is a predictor of poor short-term outcomes in a prospective cohort of minor ischemic stroke

Prior studies have shown that patients with minor ischemic stroke have substantial disability rates at hospital discharge. We sought to determine whether blood pressure variability (BPV) estimated by average real variability (ARV) is one of the predictors of poor outcome at 90 days. Four hundred fifty-one consecutive patients with ischemic stroke treated within 7 days after onset were enrolled prospectively. Baseline magnetic resonance imaging (MRI) was performed on all subjects. Blood pressure was measured for all recruited patients every 2 hours in the first 24 hours after admission, followed by measurements collected every 4 hours from day 2 to day 7 after admission. ARV was used to estimate BPV. A total of 192 patients with minor ischemic stroke were enrolled, and 11 of them (5.7%) had poor outcomes. Univariate regression analysis showed that early neurological deterioration (X² = 21.44, P = 0.000), severe symptomatic large artery stenosis or occlusion (X² = 9.260, P = 0.000), large artery atherosclerotic stroke (X² = 7.14, P = 0.002), total cholesterol (TC), and D2-7 SBP-ARV (t = 5.449, P = 0.001) of the poor outcome group were significantly higher than those of the good outcome group. Multivariate logistic regression analysis showed that early neurological deterioration (OR 4.369, 95% CI 3.54, 15.65; P = 0.001), severe symptomatic large artery stenosis or occlusion (OR 5.56, 95% CI 3.56, 13.65; P = 0.000), large artery atherosclerotic stroke (OR 3.56, 95% CI 1.45, 7.48; P = 0.004), and D2-7 SBP-ARV (OR 3.96, 95% CI 1.90, 20.18, P = 0.008) were significantly related to poor outcomes. In conclusion, approximately 5.7% of minor ischemic stroke patients had poor outcomes. D2-7 SBP-ARV, early neurologic deterioration, severe symptomatic artery stenosis or occlusion, and large atherosclerotic stroke were the independent risk factors of poor short-term outcomes.

Correlation between Very Short and Short-Term Blood Pressure Variability in Diabetic-Hypertensive and Healthy Subjects

Background

Blood pressure (BP) variability can be evaluated by 24-hour ambulatory BP monitoring (24h-ABPM), but its concordance with results from finger BP measurement (FBPM) has not been established yet.

Objective

The aim of this study was to compare parameters of short-term (24h-ABPM) with very short-term BP variability (FBPM) in healthy (C) and diabetic-hypertensive (DH) subjects.

Methods

Cross-sectional study with 51 DH subjects and 12 C subjects who underwent 24h-ABPM [extracting time-rate, standard deviation (SD), coefficient of variation (CV)] and short-term beat-to-beat recording at rest and after standing-up maneuvers [FBPM, extracting BP and heart rate (HR) variability parameters in the frequency domain, autoregressive spectral analysis]. Spearman correlation coefficient was used to correlate BP and HR variability parameters obtained from both FBPM and 24h-ABPM (divided into daytime, nighttime, and total). Statistical significance was set at p < 0.05.

Results

There was a circadian variation of BP levels in C and DH groups; systolic BP and time-rate were higher in DH subjects in all periods evaluated. In C subjects, high positive correlations were shown between time-rate index (24h-ABPM) and LF component of short-term variability (FBPM, total, R = 0.591, p = 0.043); standard deviation (24h-ABPM) with LF component BPV (FBPM, total, R = 0.608, p = 0.036), coefficient of variation (24h-ABPM) with total BPV (FBPM, daytime, -0.585, p = 0.046) and alpha index (FBPM, daytime, -0.592, p = 0.043), time rate (24h-ABPM) and delta LF/HF (FBPM, total, R = 0.636, p = 0.026; daytime R = 0,857, p < 0.001). Records obtained from DH showed weak positive correlations.

Conclusions

Indices obtained from 24h-ABPM (total, daytime) reflect BP and HR variability evaluated by FBPM in healthy individuals. This does not apply for DH subjects.

Obstructive sleep apnea increases systolic and diastolic blood pressure variability in hypertensive patients

OBJECTIVE

Obstructive sleep apnea (OSA) has been identified as the most common secondary contributing factor for the development and worsening of hypertension. However, the underlying relationships between blood pressure variability (BPV) and OSA are still not very clear. Therefore, we investigated the influences of OSA on BPV in hypertensive patients and explored the potential pathophysiologic mechanisms.

PARTICIPANTS AND METHODS

Ambulatory blood pressure (BP) monitoring was carried out and polysomnography was performed to detect sleep apnea. A total of 86 hypertensive individuals were divided into patients without OSA (n=43) and patients with severe OSA (n=43). Systolic and diastolic BPV were obtained by calculating the SD, coefficient of variation, and average real variability during day-time, night-time, and over 24 h. The relationship between OSA and BPV was assessed after adjustment for potential confounding variables (age, sex, BMI, neck circumference, heart rate, and snoring history).

RESULTS

Compared with participants without OSA, nocturnal systolic BPV and 24-h systolic BP average real variability from OSA participants were obviously increased (P<0.05), but there were no statistically significant differences in day-time and 24-h systolic BP SD and coefficient of variation (P>0.05). Compared with participants without OSA, 24-h diastolic BPV and day-time diastolic BP SD from OSA participants were markedly increased (P<0.05), but nocturnal indices showed no significant differences between the two groups.

CONCLUSION

OSA mainly increases night-time systolic and 24-h diastolic BPV in hypertensive patients. This may provide a plausible explanation for OSA remaining a major risk determinant for cardiovascular diseases.

There is a significant relationship between morning blood pressure surge and increased abdominal aortic intima-media thickness in hypertensive patients

PURPOSE

There are limited data about increased aortic intima-media thickness (A-IMT) in the presence of subclinical target organ damage in hypertensive (HT) patients. In this study, we aimed to determine the frequency of increased A-IMT, the parameters determining increased A-IMT, and the relationship between increased A-IMT and other vascular IMT measurements.

MATERIALS AND METHODS

We prospectively included 265 patients (mean age 54.1 ± 10.6 years, male/female 91/174) with essential HT. Physical examination of all patients was performed. Laboratory data and antihypertensive treatments were recorded. Twenty-four-hour ambulatory blood pressure monitoring (ABPM) was performed. Bilateral carotid, brachial, and femoral artery and abdominal A-IMT values were measured by B-mode ultrasonography (USG). Patients were categorized into two main groups: patients with increased A-IMT (≥ 3 mm) or normal A-IMT (< 3 mm).

RESULTS

Increased A-IMT was detected in 55 patients (20.8%). There was a close relationship between increased A-IMT and advanced age, presence of coronary artery disease, high morning blood pressure surge (MBPS), and bilateral carotid and femoral IMT. Parameters associated with increased A-IMT in univariate analysis were assessed by regression analysis. Left femoral IMT and MBPS were independently associated with increased A-IMT. In the regression model, each 5-mmHg elevation in MBPS increased the risk of increased A-IMT by 34.2%. The cutoff value of MBPS obtained by the ROC curve analysis was 32 mmHg for the prediction of increased A-IMT (sensitivity 76.3%, specificity 63.5%). The area under the curve was 0.784 (95% CI 0.720-0.847, p < 0.001).

CONCLUSION

Abdominal A-IMT increased at a significant rate in patients with HT. An independent association was found between MBPS and A-IMT, which can both be easily detected by ABPM and B-mode USG. The high MBPS level was considered to be a simple and inexpensive method for detecting subclinical target organ damage. A-IMT measurement should also be a part of abdominal USG, which is a routine examination in HT patients.

Coordination of cardiac rhythmic output and circadian metabolic regulation in the heart

Over the course of a 24-h day, demand on the heart rises and falls with the sleep/wake cycles of the organism. Cardiac metabolism oscillates appropriately, with the relative contributions of major energy sources changing in a circadian fashion. The cardiac peripheral clock is hypothesized to drive many of these changes, yet the precise mechanisms linking the cardiac clock to metabolism remain a source of intense investigation. Here we summarize the current understanding of circadian alterations in cardiac metabolism and physiology, with an emphasis on novel findings from unbiased transcriptomic studies. Additionally, we describe progress in elucidating the links between the cardiac peripheral clock outputs and cardiac metabolism, as well as their implications for cardiac physiology.

Visit-to-visit variability of systolic blood pressure predicts all-cause mortality in patients received percutaneous coronary intervention with drug-eluting stents

Blood pressure (BP) and its variability are associated with atherosclerotic disease and cardiovascular events. The prognostic implications of outpatient clinic visit-to-visit blood pressure variability (BPV) are unknown in patients undergoing percutaneous coronary intervention (PCI) with drug-eluting stents (DES). A total of 1,463 patients undergoing PCI with DES were consecutively enrolled from January 2009 to December 2013. We analyzed the 1,234 patients, who measured clinic BP more than three times during the first year after PCI. The BPV is determined by standard deviation of systolic and diastolic BP, and coefficient of variation. Median follow-up duration was 905 days (interquartile range 529-1,310 days). All patients were divided into two groups according to the coefficient of variation of systolic BP (CVSBP); high CVSBP group (> 8.78, n = 617) and low CVSBP group (≤ 8.78, n = 617). High CVSBP group had significantly higher all-cause mortality (7.9% versus 3.1%, p < 0.001) and composite of all-cause mortality, myocardial infarction, and stroke (13.1% versus 6.2%, p < 0.001). In multivariate logistic regression analysis for prediction of all-cause mortality, and composite of all-cause mortality, myocardial infarction, and stroke after PCI with DES, hazard ratios of high CVSBP group were 2.441 (95% of confidence interval 1.042-5.718, p = 0.040), and 1.980 (95% of confidence interval 1.125-3.485, p = 0.018). The higher visit-to-visit BPV is associated higher mortality in patients undergoing PCI with DES. The clinic measured visit-to-visit BPV may serve as a predictor of all-cause mortality after PCI with DES.

24-Hour Blood Pressure Variability Assessed by Average Real Variability: A Systematic Review and Meta-Analysis

Background

Although 24‐hour blood pressure (BP) variability (BPV) is predictive of cardiovascular outcomes independent of absolute BP levels, it is not regularly assessed in clinical practice. One possible limitation to routine BPV assessment is the lack of standardized methods for accurately estimating 24‐hour BPV. We conducted a systematic review to assess the predictive power of reported BPV indexes to address appropriate quantification of 24‐hour BPV, including the average real variability (ARV) index.

Methods and Results

Studies chosen for review were those that presented data for 24‐hour BPV in adults from meta‐analysis, longitudinal or cross‐sectional design, and examined BPV in terms of the following issues: (1) methods used to calculate and evaluate ARV; (2) assessment of 24‐hour BPV determined using noninvasive ambulatory BP monitoring; (3) multivariate analysis adjusted for covariates, including some measure of BP; (4) association of 24‐hour BPV with subclinical organ damage; and (5) the predictive value of 24‐hour BPV on target organ damage and rate of cardiovascular events. Of the 19 assessed studies, 17 reported significant associations between high ARV and the presence and progression of subclinical organ damage, as well as the incidence of hard end points, such as cardiovascular events. In all these cases, ARV remained a significant independent predictor (P<0.05) after adjustment for BP and other clinical factors. In addition, increased ARV in systolic BP was associated with risk of all cardiovascular events (hazard ratio, 1.18; 95% confidence interval, 1.09–1.27). Only 2 cross‐sectional studies did not find that high ARV was a significant risk factor.

Conclusions

Current evidence suggests that ARV index adds significant prognostic information to 24‐hour ambulatory BP monitoring and is a useful approach for studying the clinical value of BPV.

Muscle microcirculation alterations and relation to dipping status in newly diagnosed untreated patients with arterial hypertension-A pilot study

OBJECTIVE

The importance of abnormalities observed in the microcirculation of patients with arterial hypertension (AH) is being increasingly recognized. The authors aimed to evaluate skeletal muscle microcirculation in untreated, newly diagnosed hypertensive patients with NIRS, a noninvasive method that evaluates microcirculation.

METHODS

We evaluated 34 subjects, 17 patients with AH (13 males, 49±13 years, BMI: 26±2 kg/m² ) and 17 healthy controls (12 males, 49±15 years, BMI: 25±3 kg/m² ). The thenar muscle StO₂ (%) was measured by NIRS before, during and after 3-minutes vascular occlusion to calculate OCR (%/min), EF (%/min), and RHT (minute). The dipping status of hypertensive patients was assessed.

RESULTS

The RHT differed between AH patients and healthy subjects (2.6±0.3 vs 2.1±0.3 minutes, P<.001). Dippers had higher EF than nondippers (939±280 vs 710±164%/min, P=.05).

CONCLUSIONS

The study suggests an impaired muscle microcirculation in newly diagnosed, untreated AH patients.

Association Between Short-Term Systolic Blood Pressure Variability and Carotid Intima-Media Thickness in ELSA-Brasil Baseline

BACKGROUND

Blood pressure (BP) is associated with carotid intima-media thickness (CIMT), but few studies have explored the association between BP variability and CIMT. We aimed to investigate this association in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) baseline.

METHODS

We analyzed data from 7,215 participants (56.0% women) without overt cardiovascular disease (CVD) or antihypertensive use. We included 10 BP readings in varying positions during a 6-hour visit. We defined BP variability as the SD of these readings. We performed a 2-step analysis. We first linearly regressed the CIMT values on main and all-order interaction effects of the variables age, sex, body mass index, race, diabetes diagnosis, dyslipidemia diagnosis, family history of premature CVD, smoking status, and ELSA-Brasil site, and calculated the residuals (residual CIMT). We used partial least square path analysis to investigate whether residual CIMT was associated with BP central tendency and BP variability.

RESULTS

Systolic BP (SBP) variability was significantly associated with residual CIMT in models including the entire sample (path coefficient [PC]: 0.046; P < 0.001), and in women (PC: 0.046; P = 0.007) but not in men (PC: 0.037; P = 0.09). This loss of significance was probably due to the smaller subsample size, as PCs were not significantly different according to sex.

CONCLUSIONS

We found a small but significant association between SBP variability and CIMT values. This was additive to the association between SBP central tendency and CIMT values, supporting a role for high short-term SBP variability in atherosclerosis.

Differential associations of systolic and diastolic time rate of blood pressure variation with carotid atherosclerosis and plaque echogenicity

In the current study, the authors sought to assess whether the time rate of systolic and diastolic blood pressure variation is associated with advanced subclinical stages of carotid atherosclerosis and plaque echogenicity assessed by gray scale median. The authors recruited 237 consecutive patients with normotension and hypertension who underwent 24-hour ambulatory blood pressure monitoring and carotid artery ultrasonography. There was an independent association between low 24-hour systolic time rate and increased echogenicity of carotid plaques (adjusted odds ratio for highest vs lower tertiles of gray scale median, 0.470; 95% confidence interval, 0.245-0.902 [P = .023]). Moreover, increased nighttime diastolic time rate independently correlated with the presence (adjusted odds ratio, 1.328; P = .015) and number of carotid plaques (adjusted odds ratio, 1.410; P = .003). These results indicate differential associations of the systolic and diastolic components of time rate of blood pressure variation with the presence, extent, and composition of carotid plaques and suggest that when blood pressure variation is assessed, both components should be considered.

Age modifies the relation between intraindividual measurement-to-measurement variation in blood pressure and cognitive function: the Maine-Syracuse Study

BACKGROUND

There is evidence to suggest that intraindividual variability in blood pressure (BP IIV) may be superior to mean BP for predicting cognitive function, taken from both within a single visit and between-visits. BP IIV increases with age in studies of persons middle-aged and older. The aim was therefore to investigate age by BP IIV (SBP and DBP) interactions with regard to cognitive functioning while considering medication class and polypharmacy, which may also affect BP IIV with advancing age.

METHOD AND RESULTS

Cross-sectional analyses were performed on 980 community-dwelling individuals from the Maine-Syracuse Longitudinal Study. Automated BP measures were taken 15 times (five times each in sitting, reclining, and standing positions). Cognitive function was assessed using a thorough neuropsychological test battery following the BP assessment. A significant age by BP IIV interaction was observed. For individuals aged over age 60 years, IIV in SBP and DBP was inversely associated with Global Composite, Scanning and Tracking, and the Similarities test. IIV in SBP was additionally associated with Verbal Memory and the Mini-Mental State Examination. DBP IIV was additionally related to the Visual-Spatial Memory and Organization composite. There were no significant associations between BP IIV and cognitive function in those aged less than 60 years.

CONCLUSION

BP IIV is an important predictor of cognition with advancing age.

Association of Ambulatory Blood Pressure Monitoring parameters with the Framingham Stroke Risk Profile

The Framingham Stroke Risk Profile (FSRP) is a novel and reliable tool for estimating the 10-year probability for incident stroke in stroke-free individuals, while the predictive value of ambulatory blood pressure monitoring (ABPM) for first-ever and recurrent stroke has been well established. We sought to evaluate cross-sectionally the association of ABPM parameters with FSRP score in a large sample of 2343 consecutive stroke-free individuals (mean age: 56.0±12.9, 49.1% male) who underwent 24-hour ABPM. True hypertensives showed significantly higher FSRP (11.2±5.0) compared to the normotensives (8.2±5.0, p<0.001), while subjects with white coat hypertension also had higher FSRP (10.2±4.7) than normotensives (8.2±5.0, p<0.001). Compared to dippers that exhibited the lowest FSRP, non-dippers and reverse-dippers exhibited significantly higher FSRP (9.8±4.8 for dippers vs 10.6±5.2 and 11.5±5.0 for non-dippers and reverse-dippers respectively, p≤0.001 for comparisons). In univariate analyses, the ABPM parameters that had the strongest correlation with FSRP were 24-hour (r=0.440, p<0.001), daytime (r=0.435, p<0.001) and night-time (r=0.423; p<0.001) pulse pressure (PP). The best fitting model for predicting FSRP (R²=24.6%) on multiple linear regression analyses after adjustment for vascular risk factors not included in FSRP comprised the following parameters in descending order: 24-hour PP (β=0.349, p<0.001), daytime SBP variability (β=0.124, p<0.001), 24-hour HR variability (β=-0.091, p<0.001), mean 24-hour HR (β=-0.107, p<0.001), BMI (β=0.081, p<0.001) and dipping percentage (β=-0.063, p=0.001). 24-hour PP and daytime SBP variability are the two ABPM parameters that were more strongly associated with FSRP-score. Reverse dippers had the highest FSRP among all dipping status profiles.

Brain Oscillations Elicited by the Cold Pressor Test: A Putative Index of Untreated Essential Hypertension

Objective

Essential hypertension is associated with reduced pain sensitivity of unclear aetiology. This study explores this issue using the Cold Pressor Test (CPT), a reliable pain/stress model, comparing CPT-related EEG activity in first episode hypertensives and controls.

Method

22 untreated hypertensives and 18 matched normotensives underwent 24-hour ambulatory blood pressure monitoring (ABPM). EEG recordings were taken before, during, and after CPT exposure.

Results

Significant group differences in CPT-induced EEG oscillations were covaried with the most robust cardiovascular differentiators by means of a Canonical Analysis. Positive correlations were noted between ABPM variables and Delta (1–4 Hz) oscillations during the tolerance phase; in high-alpha (10–12 Hz) oscillations during the stress unit and posttest phase; and in low-alpha (8–10 Hz) oscillations during CPT phases overall. Negative correlations were found between ABPM variables and Beta2 oscillations (16.5–20 Hz) during the posttest phase and Gamma (28.5–45 Hz) oscillations during the CPT phases overall. These relationships were localised at several sites across the cerebral hemispheres with predominance in the right hemisphere and left frontal lobe.

Conclusions

These findings provide a starting point for increasing our understanding of the complex relationships between cerebral activation and cardiovascular functioning involved in regulating blood pressure changes.

Twenty-Four-Hour Blood Pressure Monitoring to Predict and Assess Impact of Renal Denervation: The DENERHTN Study (Renal Denervation for Hypertension)

The DENERHTN trial (Renal Denervation for Hypertension) confirmed the blood pressure (BP) lowering efficacy of renal denervation added to a standardized stepped-care antihypertensive treatment for resistant hypertension at 6 months. We report here the effect of denervation on 24-hour BP and its variability and look for parameters that predicted the BP response. Patients with resistant hypertension were randomly assigned to denervation plus stepped-care treatment or treatment alone (control). Average and standard deviation of 24-hour, daytime, and nighttime BP and the smoothness index were calculated on recordings performed at randomization and 6 months. Responders were defined as a 6-month 24-hour systolic BP reduction ≥20 mm Hg. Analyses were performed on the per-protocol population. The significantly greater BP reduction in the denervation group was associated with a higher smoothness index (P=0.02). Variability of 24-hour, daytime, and nighttime BP did not change significantly from baseline to 6 months in both groups. The number of responders was greater in the denervation (20/44, 44.5%) than in the control group (11/53, 20.8%; P=0.01). In the discriminant analysis, baseline average nighttime systolic BP and standard deviation were significant predictors of the systolic BP response in the denervation group only, allowing adequate responder classification of 70% of the patients. Our results show that denervation lowers ambulatory BP homogeneously over 24 hours in patients with resistant hypertension and suggest that nighttime systolic BP and variability are predictors of the BP response to denervation.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT01570777.

Remote Limb Ischemic Conditioning at Two Cuff Inflation Pressures Yields Learning Enhancements in Healthy Adults

The authors tested whether 2 doses of remote limb ischemic conditioning (RLIC), induced via blood pressure cuff inflation, enhanced motor and cognitive learning to an equal extent, and explored a panel of blood biomarkers of RLIC. Thirty-two young adults were randomized to 3 groups and underwent a 7-day protocol of RLIC/sham followed by motor and cognitive training, with follow-up. Both RLIC groups had greater motor learning and a trend toward greater cognitive learning compared with the sham group. RLIC at the lower inflation pressure was as effective as RLIC with the higher inflation pressure. No significant candidate blood biomarkers were found. RLIC could be a well-tolerated method to enhance learning and improve rehabilitation outcomes in people with neurological conditions.