Blood pressure and its variability: classic and novel measurement techniques

Blood pressure variability assessed by office, home, and ambulatory measurements before and during antihypertensive drug treatment: a sub-analysis of the REVERENT randomized trial

OBJECTIVES

Blood pressure (BP) variability (BPV) can be assessed using office (OBP), home (HBP), or ambulatory BP (ABP) measurements. This analysis investigated the association and agreement between OBP, HBP, and ABP measurements for BPV assessment at baseline and 10 weeks after initiating antihypertensive drug therapy.

METHODS

Untreated hypertensive patients with elevated BPV were randomized to receive an angiotensin-converting enzyme inhibitor (ramipril) or a calcium channel blocker (nifedipine GITS) in a 10-week, open-label, blinded-end point study. BPV was assessed using standard deviation (SD) and coefficient of variation (CV) (reading-to-reading analyses).

RESULTS

Data from 146 participants from three research centers (Athens/Greece; Milan/Italy; Shanghai/China) were analyzed [mean age 53 ± 10 (SD) years, male individuals 60%, baseline systolic OBP, HBP, and 24 h ABP 144 ± 9, 138 ± 10, and 143 ± 10 mmHg, respectively]. Post-treatment minus pre-treatment systolic CV difference was: OBP: 0.3%, P  = 0.28; HBP: -0.2%, P  = 0.20; 24 h ABP: 1.1%, P  < 0.001. Home and ambulatory (not office) BPV indices presented weak-to-moderate correlation, both before and during treatment (range of coefficients 0.04-0.33). The correlation coefficient between systolic HBP and awake ABP CV was 0.21 and 0.28 before and during treatment, respectively ( P  < 0.05/< 0.001, respectively). Home and ambulatory (not office) BPV indices presented slight-to-fair agreement (range 64-73%) in detecting participants with high systolic BPV (top quartile of respective distributions) both before and during treatment (kappa range 0.04-0.27).

CONCLUSION

These data showed a weak-to-moderate association between out-of-office (but not office) BPV indices both before and during BP-lowering treatment, with reasonable agreement in detecting individuals with high BPV. Out-of-office BP measurements provide more similar and consistent BPV information than office measurements.

Blood pressure time at target and its prognostic value for cardiovascular outcomes: a scoping review

The proportion of time that blood pressure (BP) readings are at treatment target levels, commonly referred to as time at target or time in therapeutic range (BP-TTR), is emerging as a useful measure for evaluating hypertension management effectiveness and assessing longitudinal BP control. However, method of determination for BP-TTR differs across studies. This review identifies variations in BP-TTR determination methodologies and its potential prognostic value for cardiovascular outcomes. Following PRISMA extension for scoping reviews guidelines, literature was systematically searched in Embase, PubMed, Scopus, Web of Science, and CINAHL. Relevant clinical trials, observational studies, cohort studies, cross-sectional studies, and systematic reviews published in English were screened. Of 369 articles identified, 17 articles were included. Studies differed in the BP targets used (e.g., BP < 140/90 mmHg or 130/80 mmHg; systolic BP within 110-130 mmHg or 120-140 mmHg), BP-TTR measurement duration (range 24 h to 15 years), and calculation method (linear interpolation method, n = 12 [71%]; proportion of BP readings at target, n = 5 [29%]). Regardless of method, studies consistently demonstrated that higher BP-TTR was associated with reduced risk of cardiovascular outcomes. Six of eight studies found the association was independent of mean achieved BP or last measured BP. Despite variation in methods of BP-TTR determination, these studies demonstrated the potential prognostic value of BP-TTR for cardiovascular outcomes beyond current BP control measures. We recommend standardization of BP-TTR methodology, with preference for linear interpolation method when BP measurements are few or less frequent, and proportion of BP readings method when large number of BP readings are available.

Empagliflozin combined with sacubitril/valsartan in hypertensive patients with heart failure: a retrospective study of efficacy and effect on blood pressure variability and cardiac function

OBJECTIVE

To evaluate the efficacy of empagliflozin combined with sacubitril/valsartan in treating hypertensive patients with heart failure (HF), focusing on its effects on blood pressure variability (BPV) and cardiac function.

METHODS

This retrospective study included 101 patients with hypertension and heart failure with reduced ejection fraction treated at Baoji High-Tech Hospital from October 2021 to October 2023. Patients were divided into two groups: an observation group (n=51), treated with both empagliflozin and sacubitril/valsartan, and a control group (n=50), treated with sacubitril/valsartan alone. We compared the therapeutic effects, BPV (including 24-hour, daytime, and nighttime systolic and diastolic BPV), cardiac function indicators, levels of N-terminal pro-brain natriuretic peptide (NT-proBNP) and cardiac troponin I (cTnI) before and after treatment, and the incidence of adverse reactions between the groups. Independent risk factors affecting treatment efficacy were also analyzed.

RESULTS

The total effective rate of treatment in the observation group was significantly higher than in the control group (P<0.05). Both groups showed reductions in daytime and nighttime systolic and diastolic BPV after treatment, with the observation group displaying more pronounced improvements (all P<0.05). Enhancements in cardiac ultrasound measurements, NT-proBNP levels, and cTnI levels were more significant in the observation group compared to the control group post-treatment (both P<0.05). There was no significant difference in the incidence of adverse reactions during treatment between the two groups (P>0.05). Age and comorbid diabetes were identified as independent risk factors for poor prognosis, while treatment with empagliflozin combined with sacubitril/valsartan was a protective factor.

CONCLUSION

Empagliflozin combined with sacubitril/valsartan significantly enhances treatment efficacy in hypertensive patients with heart failure, effectively improves cardiac function and BPV, and demonstrates good safety.

Recommendations for evaluating photoplethysmography-based algorithms for blood pressure assessment

Photoplethysmography (PPG) is a non-invasive optical technique that measures changes in blood volume in the microvascular tissue bed of the body. While it shows potential as a clinical tool for blood pressure (BP) assessment and hypertension management, several sources of error can affect its performance. One such source is the PPG-based algorithm, which can lead to measurement bias and inaccuracy. Here, we review seven widely used measures to assess PPG-based algorithm performance and recommend implementing standardized error evaluation steps in their development. This standardization can reduce bias and improve the reliability and accuracy of PPG-based BP estimation, leading to better health outcomes for patients managing hypertension.

Wearable cuffless blood pressure tracking: when will they be good enough?

Wearable health monitoring is a multibillion-dollar industry. But the holy grail is probably getting it right for blood pressure monitoring without a cuff, because raised blood pressure is very common and the leading cause of death in the world. Many have tried and failed, but industry is persisting: numerous cuffless wearable blood pressure devices are on the market, several technologies have been developed, hundreds of patents are registered every year, and some devices already have regulatory approval. However, to convince the die-hard blood pressure critic is a different ball game. To understand the challenges of currently accepted methods and cuffless devices, I performed a 24-h blood pressure monitoring self-test, including measurements when awake, asleep and watching an intense match of the Rugby World Cup final, with the purpose to demonstrate the challenges and opportunities we face. Blood pressure was monitored using five different devices simultaneously: validated left and right arm cuff blood pressure, and three cuffless wearable devices (wrist-band, chest patch and a ring). Whilst none of these devices proved to be perfect in capturing a physiologically challenging measure, namely blood pressure, it emphasised that our current practice of a single blood pressure measurement in clinical practice should be revisited. It further begs the question of when cuffless measurements will be good enough to incorporate in clinical decision-making.

Artificial intelligence-enhanced patient evaluation: bridging art and science

The advent of digital health and artificial intelligence (AI) has promised to revolutionize clinical care, but real-world patient evaluation has yet to witness transformative changes. As history taking and physical examination continue to rely on long-established practices, a growing pipeline of AI-enhanced digital tools may soon augment the traditional clinical encounter into a data-driven process. This article presents an evidence-backed vision of how promising AI applications may enhance traditional practices, streamlining tedious tasks while elevating diverse data sources, including AI-enabled stethoscopes, cameras, and wearable sensors, to platforms for personalized medicine and efficient care delivery. Through the lens of traditional patient evaluation, we illustrate how digital technologies may soon be interwoven into routine clinical workflows, introducing a novel paradigm of longitudinal monitoring. Finally, we provide a skeptic's view on the practical, ethical, and regulatory challenges that limit the uptake of such technologies.

Transforming Cardiovascular Care With Artificial Intelligence: From Discovery to Practice: JACC State-of-the-Art Review

Artificial intelligence (AI) has the potential to transform every facet of cardiovascular practice and research. The exponential rise in technology powered by AI is defining new frontiers in cardiovascular care, with innovations that span novel diagnostic modalities, new digital native biomarkers of disease, and high-performing tools evaluating care quality and prognosticating clinical outcomes. These digital innovations promise expanded access to cardiovascular screening and monitoring, especially among those without access to high-quality, specialized care historically. Moreover, AI is propelling biological and clinical discoveries that will make future cardiovascular care more personalized, precise, and effective. The review brings together these diverse AI innovations, highlighting developments in multimodal cardiovascular AI across clinical practice and biomedical discovery, and envisioning this new future backed by contemporary science and emerging discoveries. Finally, we define the critical path and the safeguards essential to realizing this AI-enabled future that helps achieve optimal cardiovascular health and outcomes for all.

Blood pressure and heart rate variability to assess autonomic response to an acute bout of high intensity interval exercise in healthy young adults

Autonomic nervous system (ANS) activity causes acute variations in blood pressure (BP) and heart rate (HR). These systems are challenged during high intensity interval exercise (HIIE). However, BP variability (BPV) and HR variability (HRV) response to HIIE is unknown. We characterized BPV and HRV during an acute HIIE bout using spectral low frequency [LF] and high frequency [HF] domains. We hypothesized that BPV would increase and HRV would decrease during high-intensity and active-recovery of HIIE compared to baseline [BL] and BPV would reduce and HRV would increase during cool down, post-HIIE, and 30 min post-HIIE compared to BL. HIIE involved 10 min of alternating high-intensity and active-recovery (approximately 70% and 10% of Wattmax) on a recumbent stepper. We did a secondary analysis on 23 datasets. The participants were 25 ± 1.5 years, 48% females. Our results showed high-intensity BPV LF was not significantly different from BL while HF increased. HRV LF and HF decreased compared to BL. During active-recovery, LF and HF for BPV and HRV increased greater than high-intensity. HRV LF and HF returned to BL after 30 min of recovery, whereas BPV HF was higher compared to BL. The rapid switching during HIIE uniquely modulates cardiovascular and ANS.

Free Will as Defined by the Constrained Disorder Principle: a Restricted, Mandatory, Personalized, Regulated Process for Decision-Making

The concept of free will has challenged physicists, biologists, philosophers, and other professionals for decades. The constrained disorder principle (CDP) is a fundamental law that defines systems according to their inherent variability. It provides mechanisms for adapting to dynamic environments. This work examines the CDP's perspective of free will concerning various free will theories. Per the CDP, systems lack intentions, and the "freedom" to select and act is built into their design. The "freedom" is embedded within the response range determined by the boundaries of the systems' variability. This built-in and self-generating mechanism enables systems to cope with perturbations. According to the CDP, neither dualism nor an unknown metaphysical apparatus dictates choices. Brain variability facilitates cognitive adaptation to complex, unpredictable situations across various environments. Human behaviors and decisions reflect an underlying physical variability in the brain and other organs for dealing with unpredictable noises. Choices are not predetermined but reflect the ongoing adaptation processes to dynamic prssu½res. Malfunctions and disease states are characterized by inappropriate variability, reflecting an inability to respond adequately to perturbations. Incorporating CDP-based interventions can overcome malfunctions and disease states and improve decision processes. CDP-based second-generation artificial intelligence platforms improve interventions and are being evaluated to augment personal development, wellness, and health.

Multimodal data-driven, vertical visualization prediction model for early prediction of atherosclerotic cardiovascular disease in patients with new-onset hypertension

BACKGROUND

: Hypertension is an important contributing factor to atherosclerotic cardiovascular disease (ASCVD), and multiple risk factors, many of which are implicated in metabolic disorders, contribute to the cause of hypertension. Despite the promise of multimodal data-driven prediction model, no such prediction model was available to predict the risk of ASCVD in Chinese individuals with new-onset hypertension and no history of ASCVD.

METHODS

: A total of 514 patients were randomly allocated to training and verification cohorts (ratio, 7 : 3). We employed Boruta feature selection and conducted multivariate Cox regression analyses to identify variables associated with ASCVD in these patients, which were subsequently utilized for constructing the predictive model. The performance of prediction model was assessed in terms of discriminatory power (C-index), calibration (calibration curves), and clinical utility [decision curve analysis (DCA)].

RESULTS

: This model was derived from four clinical variables: 24-h SBP coefficient of variation, 24-h DBP coefficient of variation, urea nitrogen and the triglyceride-glucose (TyG) index. Bootstrapping with 500 iterations was conducted to adjust the C-indexes were C-index = 0.731, 95% confidence interval (CI) 0.620-0.794 and C-index: 0.799, 95% CI 0.677-0.892 in the training and verification cohorts, respectively. Calibration plots with 500 bootstrapping iterations exhibited a strong correlation between the predicted and observed occurrences of ASCVD in both the training and verification cohorts. DCA analysis confirmed the clinical utility of this prediction model. The constructed nomogram demonstrated significant additional prognostic utility for ASCVD, as evidenced by improvements in the C-index, net reclassification improvement, integrated discrimination improvement, and DCA compared with the overall ASCVD risk assessment.

CONCLUSION

The developed longitudinal prediction model based on multimodal data can effectively predict ASCVD risk in individuals with an initial diagnosis of hypertension.

TRIAL REGISTRATION

: The trial was registered in the Chinese Clinical Trial Registry (ChiCTR2300074392).

The impact of sphygmomanometer placement and cuff placement on blood pressure measurements

Background

Hypertension is the most significant global risk factor for mortality and morbidity, making standardized blood pressure measurement crucial.

Objectives

To investigate whether the location of blood pressure monitors and the positioning of cuffs yield differing results in blood pressure measurements.

Methods

Patients admitted to the Affiliated Hospital of Jiujiang College between 1 January 2022 and 30 June 2023 were enrolled in this study and randomly allocated into four groups. These groups were defined based on the positioning of monitoring equipment as follows: varied placements of cuffs on automatic blood pressure monitors, different heights for mercury column blood pressure monitors, varied heights for automatic blood pressure monitors, and different orientations for the cuff airbag tubes on electrocardiogram monitors. Blood pressure was measured and recorded for each group, followed by an analysis of the variations in readings across the different setups.

Results

In the first cohort of 763 individuals, mean systolic blood pressure measured at the standard upper arm site was 128.8 ± 10.5 mmHg, compared to 125.3 ± 10.4 mmHg at the elbow fossa. The corresponding diastolic pressures were 79.2 ± 10.7 and 75.0 ± 10.6 mmHg, respectively. The difference in systolic pressure between these positions was significant at 3.48 ± 3.22 mmHg (t₁ = 29.91, p₁ < 0.001) and for diastolic pressure at 4.23 ± 1.31 mmHg (t₂ = 88.98, p₂ < 0.001). For the subsequent groups, involving 253, 312, and 225 individuals, respectively, blood pressure measurements were analyzed and compared across different methods within each group. All p-values exceeded 0.05, indicating no statistically significant differences.

Conclusions

Blood pressure values measured at the elbow fossa position using an upper arm-type automatic sphygmomanometer were found to be lower than those measured at the upper arm position, with a difference of 3.48 mmHg for systolic and 4.23 mmHg for diastolic pressures. It is therefore essential to position the cuff correctly, specifically 2-3 cm above the elbow fossa, when utilizing an upper arm-type automatic sphygmomanometer for blood pressure monitoring. Conversely, the placement of the mercury column sphygmomanometer and the automated sphygmomanometer at varying heights had no significant effect on blood pressure readings. Similarly, the orientation of the electrocardiogram's cuffed balloon tube, whether facing upward or downward, did not influence blood pressure measurement outcomes.

Smart solutions in hypertension diagnosis and management: a deep dive into artificial intelligence and modern wearables for blood pressure monitoring

Hypertension, a widespread cardiovascular issue, presents a major global health challenge. Traditional diagnosis and treatment methods involve periodic blood pressure monitoring and prescribing antihypertensive drugs. Smart technology integration in healthcare offers promising results in optimizing the diagnosis and treatment of various conditions. We investigate its role in improving hypertension diagnosis and treatment effectiveness using machine learning algorithms for early and accurate detection. Intelligent models trained on diverse datasets (encompassing physiological parameters, lifestyle factors, and genetic information) to detect subtle hypertension risk patterns. Adaptive algorithms analyze patient-specific data, optimizing treatment plans based on medication responses and lifestyle habits. This personalized approach ensures effective, minimally invasive interventions tailored to each patient. Wearables and smart sensors provide real-time health insights for proactive treatment adjustments and early complication detection.

Unravelling the Belgian cascade of hypertension care and its determinants: insights from a cross-sectional analysis

BACKGROUND

Hypertension is a major risk factor for cardiovascular disease and all-cause mortality worldwide. Despite the widespread availability of effective antihypertensives, blood pressure (BP) control rates remain suboptimal, even in high-income countries such as Belgium. In this study, we used a cascade of care approach to identify where most patients are lost along the continuum of hypertension care in Belgium, and to assess the main risk factors for attrition at various stages of hypertension management.

METHODS

Using cross-sectional data from the 2018 Belgian Health Interview Survey and the Belgian Health Examination Survey, we estimated hypertension prevalence among the Belgian population aged 40-79 years, and the proportion that was (1) screened, (2) diagnosed, (3) linked to care, (4) in treatment, (5) followed up and (6) well-controlled. Cox regression models were estimated to identify individual risk factors for being unlinked to hypertension care, untreated and not followed up appropriately.

RESULTS

The prevalence of hypertension based on self-reported and measured high BP was 43.3%. While 98% of the hypertensive population had their BP measured in the past 5 years, only 56.7% were diagnosed. Furthermore, 53.4% were linked to care, 49.8% were in treatment and 43.4% received adequate follow-up. Less than a quarter (23.5%) achieved BP control. Among those diagnosed with hypertension, males, those of younger age, without comorbidities, and smokers, were more likely to be unlinked to care. Once in care, younger age, lower BMI, financial hardship, and psychological distress were associated with a higher risk of being untreated. Finally, among those treated for hypertension, females, those of younger age, and without comorbidities were more likely to receive no adequate follow-up.

CONCLUSION

Our results show that undiagnosed hypertension is the most significant barrier to BP control in Belgium. Health interventions are thus needed to improve the accurate and timely diagnosis of hypertension. Once diagnosed, the Belgian health system retains patients fairly well along the continuum of hypertension care, yet targeted health interventions to improve hypertension management for high-risk groups remain necessary, especially with regard to improving treatment rates.

Exercise blood pressure, cardiorespiratory fitness, fatness and cardiovascular risk in children and adolescents

Cardiovascular disease remains the leading cause of mortality on a global scale. Individuals who possess risk factors for cardiovascular disease, such as high blood pressure (BP) and obesity, face an elevated risk of experiencing organ-specific pathophysiological changes. This damage includes pathophysiological changes in the heart and peripheral vascular systems, such as ventricular hypertrophy, arterial stiffening, and vascular narrowing and stenosis. Consequently, these damages are associated with an increased risk of developing severe cardiovascular outcomes including stroke, myocardial infarction, heart failure, and coronary heart disease. Among all the risk factors associated with cardiovascular disease, high blood pressure emerges as the most prominent. However, conventional resting BP measurement methods such as auscultatory or oscillometric methods may fail to identify many individuals with asymptomatic high BP. Recently, exercise BP has emerged as a valuable diagnostic tool for identifying real (high) blood pressure levels and assessing underlying cardiovascular risk, in addition to resting BP measurements in adults. Furthermore, numerous established factors, such as low cardiorespiratory fitness and high body fatness, have been confirmed to contribute to exercise BP and the associated cardiovascular risk. Modifying these factors may help reduce high exercise BP and, consequently, alleviate the burden of cardiovascular disease. A significant body of evidence has demonstrated cardiovascular disease in later life have their origins in early life. Children and adolescents with these cardiovascular risk factors also possess a greater propensity to develop cardiovascular diseases later in life. Nevertheless, the majority of previous studies on the clinical utility of exercise BP have been conducted in middle-to-older aged populations, often with pre-existing clinical conditions. Therefore, there is a need to investigate further of the factors influencing exercise BP in adolescence and its association with cardiovascular risk in early life. Our previously published work showed that exercise BP is a potential useful method to detect adolescents with increased cardiovascular risk. Children and adolescents with cardiovascular risk factors are more likely to develop cardiovascular diseases later in life. However, previous studies on the clinical utility of exercise BP have largely focused on middle-to-older aged populations with pre-existing clinical conditions. Therefore, there is a need to investigate further the factors influencing exercise BP in adolescence and its association with future cardiovascular risk. Our previous studies, which focused on exercise BP measured at submaximal intensity, have shown that exercise BP is a potentially useful method for identifying adolescents at increased cardiovascular risk. Our previous findings suggest that improving cardio-respiratory fitness and reducing body fatness may help to reduce the risk of developing cardiovascular disease and improve overall cardiovascular health. These findings have important implications for the development of effective prevention and early detection strategies, which can contribute to improved public health outcomes.

Combined effect of time in target range and variability of systolic blood pressure on cardiovascular outcomes and mortality in patients with hypertension: A prospective cohort study

Time in target range (TTR) and blood pressure variability (BPV) of systolic blood pressure (SBP) are independent risk factors for major adverse cardiovascular events (MACE) and all-cause mortality in hypertensive patients. However, the association of the combination of low TTR and high BPV of SBP with the risk of MACE and all-cause mortality is unclear. This study sought to investigate the combined effect of the TTR and BPV on the risk of MACE and all-cause mortality in patients with hypertension. A total of 11 496 hypertensive patients from the Kailuan cohort study were included in our study. All participants were divided into four groups according to their TTR and BPV levels. Cox proportional hazards regression models were used to calculate the hazard ratios (HRs) and 95% confidence interval (CI) for incident MACE and all-cause mortality. During a median follow-up of 5.64 years, 839 MACEs (included 99 cases of myocardial infarction, 591 cases of stroke, and 191 cases of heart failure) and 621 deaths occurred. Compared with the high-TTR and low-BPV group, the HRs (95% CI) of MACE and all-cause mortality were 1.309 (1.025-1.671) and 1.842 (1.373-2.473) for the high-TTR and high-BPV group, 1.692 (1.347-2.125) and 1.731 (1.298-2.309) for the low-TTR & low-BPV group, 2.132 (1.728-2.629) and 2.247 (1.722-2.932) for the low-TTR & high-BPV group. Our study suggests that the combination of low TTR and high BPV of SBP was associated with a higher risk of MACE and all-cause mortality in patients with hypertension.

Abnormal blood pressure dipping pattern: frequency, determinants, and correlates in Diabetes Mellitus patients in the Cardiovascular Health Risk Assessment in Diabetes Mellitus (CHiD) study

Purpose

Non-dipping status is associated with increased total and cardiovascular mortality in many disease conditions including diabetes mellitus. The pattern and its implications are not well described among Africans. This study was done to describe the frequency of abnormal blood pressure (BP) dipping among T2DM subjects, its determinants and correlates in Ogbomoso, Nigeria.

Methods

This was a cross-sectional study done at the LAUTECH Teaching Hospital, Ogbomoso. One hundred individuals diagnosed with T2DM were recruited and they had 24-hour ambulatory BP monitoring, echocardiography, ECG, and carotid Doppler among other evaluations. Statistical analysis was done using SPSS 27.0 (Chicago Ill, USA).

Results

The mean age of the participants was 59.3 ± 10.8 years, mean body mass index 27.7 ± 5.9 kg/m2 with a mean duration of diabetes of 7.52 ± 5.54 years. Abnormal BP dipping was present in 89% (consisting of 41% or reverse dippers and 48% non-dippers). T2DM subjects with abnormal dipping pattern were more likely to be females, had higher glycated haemoglobin, lower fractional shortening, higher left atrial volume and left ventricular mass index, and a higher DM duration than those with normal BP dipping status. The major determinants of abnormal dipping pattern were the duration of diabetes and low HDL-C concentration.

Conclusion

Abnormal BP dipping pattern is highly prevalent in T2DM subjects, especially among females. Abnormal BP dipping was also associated with markers of increased cardiovascular risk such as impaired kidney function, left ventricular hypertrophy, postural hypotension, history of intermittent claudication, and presence of plaques on carotid Doppler studies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-023-01337-8.

Systolic blood pressure visit-to-visit variability and outcomes in Asian patients with atrial fibrillation

We aimed to assess the association between SBP-VVV and outcomes in Asian patients with atrial fibrillation (AF). AF patients in the COOL-AF registry with SBP measured at baseline, and at least two other visits were studied. We defined SBP-VVV using the standard deviation (SD) of average SBP. Patients were categorized according to the quartiles of SBP SD. The associations between SBP-VVV and outcomes were assessed in the adjusted Cox model. We studied 3172 patients (mean age 67.7 years; 41.8% female), with the prevalence of hypertension being 69%. Warfarin was used in 69% of patients, whereas 7% received non-vitamin K antagonist oral anticoagulants. The minimum and maximum SD of average SBP in the study population was 0.58 and 56.38 mmHg respectively. The cutoff of SD of average SBP for each quartile in our study were 9.09, 12.15, and 16.21 mmHg. The rates of all-cause mortality, ischemic stroke or systemic embolization (SSE), major bleeding, and intracranial hemorrhage (ICH) were 3.10, 1.42, 2.09, and 0.64 per 100 person-years, respectively. Compared with the first quartile, patients in the fourth quartile had a significantly higher risk of mortality (adjusted HR 1.60, 95%CI 1.13-2.25), bleeding (aHR 1.92, 95%CI 1.25-2.96) and ICH (aHR 3.51, 95%CI 1.40-8.76). The risk of SSE was not significantly different among the quartiles. SBP-VVV had a significant impact on the long-term outcomes of Asian patients with AF, particularly mortality and bleeding. Adequate SBP control and maintaining SBP stability over time may improve outcomes for AF patients.

Prognostic Impact of Metabolic Syndrome and Steatotic Liver Disease in Hepatocellular Carcinoma Using Machine Learning Techniques

Metabolic dysfunction-associated steatotic liver disease (MASLD) currently represents the predominant cause of chronic liver disease and is closely linked to a significant increase in the risk of hepatocellular carcinoma (HCC), even in the absence of liver cirrhosis. In this retrospective multicenter study, machine learning (ML) methods were employed to investigate the relationship between metabolic profile and prognosis at diagnosis in a total of 219 HCC patients. The eXtreme Gradient Boosting (XGB) method demonstrated superiority in identifying mortality predictors in our patients. Etiology was the most determining prognostic factor followed by Barcelona Clinic Liver Cancer (BCLC) and Eastern Cooperative Oncology Group (ECOG) classifications. Variables related to the development of hepatic steatosis and metabolic syndrome, such as elevated levels of alkaline phosphatase (ALP), uric acid, obesity, alcohol consumption, and high blood pressure (HBP), had a significant impact on mortality prediction. This study underscores the importance of metabolic syndrome as a determining factor in the progression of HCC secondary to MASLD. The use of ML techniques provides an effective tool to improve risk stratification and individualized therapeutic management in these patients.

Novel Metric for Non-Invasive Beat-to-Beat Blood Pressure Measurements Demonstrates Physiological Blood Pressure Fluctuations during Pregnancy

Beat-to-beat (B2B) variability in biomedical signals has been shown to have high diagnostic power in the treatment of various cardiovascular and autonomic disorders. In recent years, new techniques and devices have been developed to enable non-invasive blood pressure (BP) measurements. In this work, we aim to establish the concept of two-dimensional signal warping, an approved method from ECG signal processing, for non-invasive continuous BP signals. To this end, we introduce a novel BP-specific beat annotation algorithm and a B2B-BP fluctuation (B2B-BPF) metric novel for BP measurements that considers the entire BP waveform. In addition to careful validation with synthetic data, we applied the generated analysis pipeline to non-invasive continuous BP signals of 44 healthy pregnant women (30.9 ± 5.7 years) between the 21st and 30th week of gestation (WOG). In line with established variability metrics, a significant increase (p < 0.05) in B2B-BPF can be observed with advancing WOGs. Our processing pipeline enables robust extraction of B2B-BPF, demonstrates the influence of various factors such as increasing WOG or exercise on blood pressure during pregnancy, and indicates the potential of novel non-invasive biosignal sensing techniques in diagnostics. The results represent B2B-BP changes in healthy pregnant women and allow for future comparison with those signals acquired from women with hypertensive disorders.

Association between antihypertensive treatment, blood pressure variability, and stroke severity and outcomes in acute ischemic stroke

OBJECTIVES

The management of blood pressure (BP) and the role of antihypertensive medications (AHT) in acute ischemic stroke (AIS) remain uncertain. This study aimed to investigate the impact of pre- and intra-stroke AHT use on systolic (SBP), diastolic (DBP), and blood pressure variability (BPV).

MATERIALS AND METHODS

A post-hoc analysis was conducted on 228 AIS patients from the PREVISE study. All patients underwent 24-hour ambulatory blood pressure monitoring within 48 h of symptom onset. Clinical and laboratory data, as well as AHT details, were recorded. Mean BP parameters and BPV for SBP and DBP were computed. The study endpoint was 3-month mortality.

RESULTS

The majority of stroke patients (84.2%) were already taking AHTs. Beta blockers and ACE inhibitors use before and after stroke were linked to higher DBP variability. Prior angiotensin receptor blockers (ARBs) and vasodilators use correlated with increased SBP variability and lower daytime SBP/DBP levels, respectively. The continuation, discontinuation, or change of AHTs after stroke onset did not significantly affect outcomes. Patients under AHTs during AIS exhibited reduced mortality, with those previously using calcium channel blockers experiencing less severe strokes, and those previously using ARBs showing better outcomes at three months.

CONCLUSIONS

These findings advocate for personalized BP management in AIS, based on a patient's antihypertensive history. These insights could enhance treatment efficacy, guide research, and improve care for acute ischemic stroke patients.

Effect of lidocaine on intraoperative blood pressure variability in patients undergoing major vascular surgery

BACKGROUND

Dynamic fluctuations of arterial blood pressure known as blood pressure variability (BPV) may have short and long-term undesirable consequences. During surgical procedures blood pressure is usually measured in equal intervals allowing to assess its intraoperative variability, which significance for peri and post-operative period is still under debate. Lidocaine has positive cardiovascular effects, which may go beyond its antiarrhythmic activity. The aim of the study was to verify whether the use of intravenous lidocaine may affect intraoperative BPV in patients undergoing major vascular procedures.

METHODS

We performed a post-hoc analysis of the data collected during the previous randomized clinical trial by Gajniak et al. In the original study patients undergoing elective abdominal aorta and/or iliac arteries open surgery were randomized into two groups to receive intravenous infusion of 1% lidocaine or placebo at the same infusion rate based on ideal body weight, in concomitance with general anesthesia. We analyzed systolic (SBP), diastolic (DBP) and mean arterial blood (MAP) pressure recorded in 5-minute intervals (from the first measurement before induction of general anaesthesia until the last after emergence from anaesthesia). Blood pressure variability was then calculated for SBP and MAP, and expressed as: standard deviation (SD), coefficient of variation (CV), average real variability (ARV) and coefficient of hemodynamic stability (C10%), and compared between both groups.

RESULTS

All calculated indexes were comparable between groups. In the lidocaine and placebo groups systolic blood pressure SD, CV, AVR and C10% were 20.17 vs. 19.28, 16.40 vs. 15.64, 14.74 vs. 14.08 and 0.45 vs. 0.45 respectively. No differences were observed regarding type of surgery, operating and anaesthetic time, administration of vasoactive agents and intravenous fluids, including blood products.

CONCLUSION

In high-risk vascular surgery performed under general anesthesia, lidocaine infusion had no effect on arterial blood pressure variability.

TRIAL REGISTRATION

ClinicalTrials.gov; NCT04691726 post-hoc analysis; date of registration 31/12/2020.

Serum Brain Natriuretic Peptide Levels Correlate with the Severity of Hypertension in a Population of Nigerian Patients

Background

Hypertension is a major global health concern requiring precise risk assessment. Brain Natriuretic Peptide (BNP) has emerged as a potential biomarker, but its relationship with hypertension severity requires exploration to evaluate its potential as a risk prediction tool. This study aimed to assess the relationship between serum BNP levels and the severity of hypertension in a population of Nigerian patients.

Methodology

This was an analytical cross-sectional case-controlled study involving 103 hypertensive patients and 98 controls. Participants were grouped based on World Health Organization (WHO) criteria for diagnosis of Hypertension and the severity of hypertension was categorized based on blood pressure readings. The mean BNP levels were assessed among different hypertension grades, while logistic regression was used to assess the odds of higher severity with elevated BNP.

Results

Serum BNP levels were significantly higher in hypertensive individuals (616.5 ± 66.3 pg/mL) compared to controls (501.1 ± 84.6 pg/mL) and varied significantly across different hypertension grades (p = 0.000). A positive correlation was observed between serum BNP and hypertension severity (r = 0.736, p < 0.001). Logistic regression analysis indicated increasing odds of higher severity with elevated BNP from Grade 1 to Grade 3 hypertension.

Conclusion

This study established a positive correlation between serum BNP levels and hypertension severity, indicating its potential as a predictive biomarker for risk stratification in hypertensive individuals.

Blood pressure and variability responses to the down-titration of antihypertensive drugs

OBJECTIVES

Several recent guidelines have proposed the gradual reduction of antihypertensive drugs for patients with well controlled blood pressure (BP). However, no studies have examined alterations in BP variability (BPV) during the down-titration of antihypertensives. This study aims to investigate changes in home BPV during the down-titration of antihypertensives.

METHODS

We analyzed 83 hypertensive patients who underwent down-titration of antihypertensives and had available home BP data during the down-titration. Down-titration was performed when home SBP was less than 120 mmHg, regardless of the clinic SBP. Primary exposure variable was the standard deviation (SD) of home BP.

RESULTS

Among 83 patients (mean age 66.3 ± 11.9 years; 45.8% men), down-titration led to increase home SBP (from 110.5 to 118.7 mmHg; P  < 0.001), and home DBP (from 68.8 to 72.8 mmHg; P  = 0.001) significantly. There were no significant differences in SDs of SBP [from 6.02 ± 3.79 to 5.76 ± 3.09 in morning, P  = 0.570; from 6.13 ± 3.32 to 6.63 ± 3.70 in evening, P  = 0.077; and from 6.54 (4.80, 8.31) to 6.37 (4.65, 8.76) in home SBP, P  = 0.464] and SDs of DBP during the down-titration of antihypertensive drugs.

CONCLUSION

Down-titration of antihypertensive drugs did not have notable impact on clinic BP and home BPV, while significantly increasing home BP. These findings provide important insights indicating that the potential concern related to an increase in BPV in the planned strategy of reducing antihypertensive drugs is not substantial.

Prognostic utility of rhythmic components in 24-h ambulatory blood pressure monitoring for the risk stratification of chronic kidney disease patients with cardiovascular co-morbidity

Chronic kidney disease (CKD) represents a significant global burden. Hypertension is a modifiable risk factor for rapid progression of CKD. We extend the risk stratification by introducing the non-parametric determination of rhythmic components in 24-h profiles of ambulatory blood pressure monitoring (ABPM) in the Chronic Renal Insufficiency Cohort (CRIC) and the African American Study for Kidney Disease and Hypertension (AASK) cohort using Cox proportional hazards models. We find that rhythmic profiling of BP through JTK_CYCLE analysis identifies subgroups of CRIC participants that were more likely to die due to cardiovascular causes. While our fully adjusted model shows a trend towards a significant association between absent cyclic components and cardiovascular death in the full CRIC cohort (HR: 1.71,95% CI: 0.99-2.97, p = 0.056), CRIC participants with a history of cardiovascular disease (CVD) and absent cyclic components in their BP profile had at any time a 3.4-times higher risk of cardiovascular death than CVD patients with cyclic components present in their BP profile (HR: 3.37, 95% CI: 1.45-7.87, p = 0.005). This increased risk was not explained by the dipping or non-dipping pattern in ABPM. Due to the large differences in patient characteristics, the results do not replicate in the AASK cohort. This study suggests rhythmic blood pressure components as a potential novel biomarker to unmask excess risk among CKD patients with prior cardiovascular disease.

Reliability of beat-to-beat blood pressure variability in older adults

Blood pressure variability (BPV) is emerging as an important risk factor across numerous disease states, including cerebrovascular and neurodegenerative disease in older adults. However, there is no current consensus regarding specific use cases for the numerous available BPV metrics. There is also little published data supporting the ability to reliably measure BPV across metrics in older adults. BPV metrics were derived from continuous beat-to-beat blood pressure monitoring data. Two sequential 7-minute waveforms were analyzed. Absolute and relative reliability testing was performed. Differences between antihypertensive medication users and non-users on BPV metric reliability was also assessed. All sequence and dispersion based BPV metrics displayed good test-retest reliability. A measure of BP instability displayed only moderate reliability. Systolic and diastolic average real variability displayed the highest levels of reliability at ICC= .87 and .82 respectively. Additionally, systolic average real variability was the most reliable metric in both the antihypertensive use group, and the no antihypertensive use group. Beat-to-beat dispersion and sequence-based metrics of BPV can be reliably obtained from older adults using noninvasive continuous blood pressure monitoring. Average real variability may be the most reliable and specific beat-to-beat blood pressure variability metric due to its decreased susceptibility to outliers and low frequency blood pressure oscillations.

Association of Variability and Hypertensive Loads in 24-h Blood Pressure With Mortality and Cardiovascular Risk

BACKGROUND

Evidence shows that high 24-h blood pressure (BP) variability increases cardiovascular risk. We investigated whether 24-h BP variability relates to mortality and cardiovascular risk due to inherent variability and/or hypertensive loads in 24-h BP.

METHODS

A total of 1,050 participants from the Maracaibo Aging Study (mean age, 66 years; women, 67.2%) underwent 24-h ambulatory BP monitoring and were followed between 2001 and 2016. To evaluate inherent BP variability, we used average real variability (ARV) as it captures variability among consecutive BP readings. 24-h systolic BP load was the proportion (%) of systolic BP readings ≥130 mm Hg during the daytime and ≥110 during the nighttime. Our primary endpoint was total mortality and major adverse cardiovascular endpoints (MACE). Statistics included Cox proportional models.

RESULTS

During a median follow-up of 8.3 years, 299 participants died and 210 experienced MACE. Each +2 mm Hg (corresponding to 1-standard deviation) higher 24-h systolic ARV (mean value, 9.0 ± 2.0 mm Hg) was associated with higher hazard ratios (HRs) for mortality by 1.28-fold (95% confidence interval [CI], 1.14-1.43) and for MACE by 1.24-fold (95% CI, 1.08-1.42). Each 30% higher 24-h systolic BP load (median value, 63%) was associated with mortality and MACE with HRs of 1.29 (95% CI, 1.15-1.46) and 1.28 (95% CI, 1.10-1.48); respectively. After models were additionally adjusted by BP level, only ARV was associated with mortality (HR, 1.17; 95% CI, 1.04-1.33) and MACE (HR, 1.16; 95% CI, 1.00-1.34).

CONCLUSIONS

High ARV and hypertensive loads in 24-h systolic BP were associated with mortality and cardiovascular risk, however, only ARV is associated independently of the BP level.

Associations of Temporal Cardiometabolic Patterns and Incident SARS-CoV-2 Infection Among U.S. Blood Donors With Serologic Evidence of Vaccination

Introduction

Cardiometabolic diseases are associated with greater COVID-19 severity; however, the influences of cardiometabolic health on SARS-CoV-2 infections after vaccination remain unclear. Our objective was to investigate the associations between temporal blood pressure and total cholesterol patterns and incident SARS-CoV-2 infections among those with serologic evidence of vaccination.

Methods

In this prospective cohort of blood donors, blood samples were collected in 2020-2021 and assayed for binding antibodies of SARS-CoV-2 nucleocapsid protein antibody seropositivity. We categorized participants into intraindividual pattern subgroups of blood pressure and total cholesterol (persistently, intermittently, or not elevated [systolic blood pressure <130 mmHg, diastolic blood pressure <80 mmHg, total cholesterol <200 mg/dL]) across the study time points.

Results

Among 13,930 donors with 39,736 donations representing 1,127,071 person-days, there were 221 incident SARS-CoV-2 infections among those with serologic evidence of vaccination (1.6%). Intermittent hypertension was associated with greater SARS-CoV-2 infections among those with serologic evidence of vaccination risk (adjusted incidence rate ratio=2.07; 95% CI=1.44, 2.96; p<0.01) than among participants with consistent normotension on the basis of a multivariable Poisson regression. Among men, intermittently elevated total cholesterol (adjusted incidence rate ratio=1.90; 95% CI=1.32, 2.74; p<0.01) and higher BMI at baseline (adjusted hazard ratio=1.44; 95% CI=1.07, 1.93; p=0.01; per 10 units) were associated with greater SARS-CoV-2 infections among those with serologic evidence of vaccination probability; these associations were null among women (both p>0.05).

Conclusions

Our findings underscore that the benefits of cardiometabolic health, particularly blood pressure, include a lower risk of SARS-CoV-2 infection after vaccination.

Arsenic Exposure-Related Hypertension in Bangladesh and Reduced Circulating Nitric Oxide Bioavailability

BACKGROUND

Hypertension is a major cause of death worldwide. Although arsenic exposure has been associated with the risk of hypertension, this association appears nonuniform due to inconsistent results from studies conducted in different populations. Moreover, hypertension is a complex condition with multiple underlying mechanisms and factors. One factor is impaired production and bioavailability of vascular nitric oxide (NO). However, the implications of the effects of arsenic exposure on circulating NO and its association with hypertension in humans are largely unknown.

OBJECTIVE

We investigated the dose-response relationship between arsenic exposure and hypertension with vascular NO levels as a potential mediator of arsenic-related hypertension in individuals exposed to a broad range of arsenic.

METHODS

A total of 828 participants were recruited from low- and high-arsenic exposure areas in Bangladesh. Participants' drinking water, hair, and nail arsenic concentrations were measured by inductively coupled plasma mass spectroscopy. Hypertension was defined as a systolic blood pressure (SBP) value of ≥ 140 and a diastolic (DBP) value of ≥ 90  mmHg . Serum NO levels reflected by total serum nitrite concentrations were measured by immunoassay. A formal causal mediation analysis was used to assess NO as a mediator of the association between arsenic level and hypertension.

RESULTS

Increasing concentrations of arsenic measured in drinking water, hair, and nails were associated with the increasing levels of SBP and DBP. The odds of hypertension were dose-dependently increased by arsenic even in participants exposed to relatively low to moderate levels (10 - 50 μ g / L ) of water arsenic [odds ratios (ORs) and 95% confidence intervals (CIs): 2.87 (95% CI: 1.28, 6.44), 2.67 (95% CI: 1.27, 5.60), and 5.04 (95% CI: 2.71, 9.35) for the 10 - 50 μ g / L , 50.01 - 150 μ g / L , and > 150 μ g / L groups, respectively]. Causal mediation analysis showed a significant mediating effect of NO on arsenic-related SBP, DBP, and hypertension.

CONCLUSION

Increasing exposure to arsenic was associated with increasing odds of hypertension. The association was mediated through the reduction of vascular NO bioavailability, suggesting that impaired NO bioavailability was a plausible underlying mechanism of arsenic-induced hypertension in this Bangladeshi population. https://doi.org/10.1289/EHP13018.

Interdialytic home systolic blood pressure variability increases all-cause mortality in hemodialysis patients

BACKGROUND

The association between Interdialytic home blood pressure variability (BPV) and the prognosis of patients undergoing maintenance hemodialysis (MHD) largely unknown.

HYPOTHESIS

We proposed the hypothesis that interdialytic home BPV exert effect on cardiac and all-cause mortality among individuals undergoing MHD.

METHODS

A total of 158 patients receiving MHD at the hemodialysis unit of Wuhan Fourth Hospital between December 2019 and August 2020 were included in this prospective cohort study. Patients were divided into tertiles according to the systolic BPV (SBPV), and the primary endpoints were cardiac and all-cause death. Kaplan-Meier analysis was used to assess the relationship between long-term survival and interdialytic home SBPV. In addition, Cox proportional hazards regression models were used to identify risk factors contributing to poor prognosis.

RESULTS

The risk of cardiac death and all-cause death was gradually increased in patients according to tertiles of SBPV (3.5% vs. 14.8% vs. 19.2%, p for trend = .021; and 11.5% vs. 27.8% vs. 44.2%, p for trend <.001). The Cox regression analysis revealed that compared to Tertile 1, the hazard ratios for all-cause mortality in Tertile 2 and Tertile 3 were 3.13 (p = .026) and 3.24 (p = .021), respectively, after adjustment for a series of covariates.

CONCLUSIONS

The findings revealed a positive correlation between increased interdialytic home SBPV and elevated mortality risk in patients with MHD.

History and evolution of blood pressure measurement

Hypertension is the leading cause of morbidity and mortality worldwide. Hypertension mostly accompanies no symptoms, and therefore blood pressure (BP) measurement is the only way for early recognition and timely treatment. Methods for BP measurement have a long history of development and improvement. Invasive method via arterial cannulation was first proven possible in the 1800's. Subsequent scientific progress led to the development of the auscultatory method, also known as Korotkoff' sound, and the oscillometric method, which enabled clinically available BP measurement. However, hypertension management status is still poor. Globally, less than half of adults are aware of their hypertension diagnosis, and only one-third of them being treated are under control. Novel methods are actively investigated thanks to technological advances such as sensors and machine learning in addition to the clinical needs for easier and more convenient BP measurement. Each method adopts different technologies with its own specific advantages and disadvantages. Promises of novel methods include comprehensive information on out-of-office BP capturing dynamic short-term and long-term fluctuations. However, there are still pitfalls such as the need for regular calibration since most novel methods capture relative BP changes rather than an absolute value. In addition, there is growing concern on their accuracy and precision as conventional validation protocols are inappropriate for cuffless continuous methods. In this article, we provide a comprehensive overview of the past and present of BP measurement methods. Novel and emerging technologies are also introduced with respect to their potential applications and limitations.

Blood pressure variability predicts poor outcomes in acute stroke patients without thrombolysis: a systematic review and meta-analysis

BACKGROUND

Stroke is a significant medical condition, and blood pressure stands out as the most prevalent treatable risk factor associated with it. Researches link blood pressure variability (BPV) with stroke; however, the specific relationship between with the outcomes of stroke patients remains unclear. As blood pressure variability and mean blood pressure are interrelated, it remains uncertain whether BPV adds additional information to understanding the outcome of acute stroke patients.

OBJECTIVE

To systematically review studies investigating the association between blood pressure variability and prognosis in acute stroke patients.

METHODS

Embase, PubMed, Web of Science, and the Cochrane Library were searched for English language full-text articles from the inception to 1 January 2023. Stroke patients aged ≥ 18 years were included in this analysis. Stroke types were not restricted.

RESULTS

This meta-analysis shows that higher systolic blood pressure variability is linked to a higher risk of poor outcome, including function disability, mortality, early neurological deterioration, and stroke recurrence, among acute stroke patients without thrombolysis. A higher diastolic blood pressure variability is linked with to a higher risk of mortality and functional disability.

CONCLUSIONS

This review reveals that blood pressure variability is a novel and clinically relevant risk factor for stroke patients' outcome. Future studies should investigate how best to measure and define BPV in acute stroke. Larger studies are warranted to provide more robust evidence in this area.

Seasonal effects on blood pressure variability in treated hypertensive patients assessed by office, home, and ambulatory measurements

This study investigated the seasonal effect on blood pressure (BP) variability. Patients on stable antihypertensive drug treatment were assessed with office (OBP), home (HBP), and ambulatory BP (ABP) measurements in winter, next summer, and in next winter. Fifty-eight participants with full data for winter and summer were analyzed (mean age 65.2 ± 7.9 [SD], 64% males). OBP, HBP and ABP (24-h; daytime) were lower in summer than in winter (P < 0.01), whereas nighttime ABP was unchanged (p = NS). Standard deviation (SD), coefficient of variation (CV) and average real variability (ARV) for systolic OBP were higher in winter than summer (p < 0.01/ < 0.05/ < 0.01, respectively). These indices for HBP and ABP measurements did not differ in winter and summer (p = NS). Forty participants had complete data for winter-summer-next winter and HBP/ABP variability indices did not differ for both winters versus summer. These preliminary data suggest that BP variability is unaffected by seasonal changes in contrast to average BP levels.

A pilot study exploring novel contexts for out-of-office blood pressure measurement

Introduction

Out-of-office blood pressure (BP) monitoring is increasingly valuable in the diagnosis and management of hypertension. With advances in wearable BP technologies, the ability to gain insight into BP outside of traditional centers of care has expanded greatly.

Methods

Here we explore the usability of a novel, wrist-worn BP cuff monitor for out-of-office data collection with participants following digital cues rather than in-person instruction. Transmitted measurements were used to evaluate BP variation with the time of day and day of week, BP variation with mood, and orthostatic measurements.

Results

Fifty participants, with a mean age of 44.5 years, were enrolled and received the BP monitor. 82% of the participants transmitted data via the smartphone application, and the median wear time of the device during the 4-week study was 11 days (IQR 8-17).

Discussion

This prospective digital pilot study illustrates the usability of wearable oscillometric BP technology combined with digital cues via a smartphone application to obtain complex out-of-office BP measurements, including orthostatic vital signs and BP associated with emotion. 25 out of 32 participants who attempted orthostatic vital signs based on in-app instruction were able to do so correctly, while 24 participants transmitted BP readings associated with emotion, with a significant difference in BP noted between calm and stressed emotional states.

Long-term systolic blood pressure variability independent of mean blood pressure is associated with mortality and cardiovascular events: A systematic review and meta-analysis

The association between long-term systolic blood pressure variability (SBPV) and cardiovascular (CV) outcomes after being adjusted with mean blood pressure (BP) is questionable. This systematic review aims to evaluate the associations between mean BP adjusted long-term SBPV and CV outcomes. A systematic search was conducted on PubMed, Scopus, and Science Direct on January 4, 2023. A total of 9,944,254 subjects from 43 studies were included in this meta-analysis. Long-term SBPV increased the risk of all-cause mortality (HR 1.21 [95%CI 1.16-1.25], I2=100%), CV mortality (HR 1.10 [95%CI 1.07-11.4], I2 = 90%), MACE (HR 1.10 [1.07-1.13], I2 = 91%), cerebrovascular stroke (HR 1.22 [1.16-1.29], I2=100%), and myocardial infarction (HR 1.13 [95%CI (1.07-1.19)], I2=91%). European populations generally had higher risk compared to other continents. In conclusion, long-term SBPV is associated with all-cause mortality, CV mortality, MACE, MI, and stroke. Poor outcomes related to long-term SBPV seem more dominated by cerebrovascular than coronary events.

Blood Pressure Variability and Autonomic Response to an Acute Bout of High Intensity Interval Exercise in Healthy Young Adults

Autonomic nervous system (ANS) activity causes acute variations in the blood pressure. Blood pressure responds to high intensity interval exercise (HIIE) repeatedly during alternating intensities, however, ANS response to the changing intensities of HIIE is unknown. We characterized the response of beat-to-beat blood pressure variability (BTB BPV) to an acute bout of HIIE using coefficient of variation (CoV) and spectral low frequency [LF], and high frequency [HF] domains. Our hypotheses were mean arterial pressure BTB BPV, would increase during 1) high intensity and 2) active recovery of HIIE compared to baseline (BL). BTB BPV would reduce during 1) cool down 2) post HIIE 3) 30 minutes post HIIE compared to BL in young adults. HIIE included bouts of 1-minute high-intensity separated by 1-minute recovery (□70% and 10% estimated Wattmax) for total of 10 minutes on a recumbent stepper. A secondary analysis was performed using twenty-one datasets of young individuals (age 25±1.5, 48% female). During high intensity, LF and HF increased compared to BL (p < 0.05) indicating increased sympathetic activity and breathing. During active recovery, LF and HF remained elevated above BL and were greater than during high intensity (p ≤ 0.02). Sympathetic activity reduced back to BL immediately post HIIE but returned to being higher than BL at 30 minutes after HIIE (p=0.001). BTB BPV CoV also increased during HIIE compared to BL (p<0.05). Results suggest that young healthy individuals have increased BTB BPV during HIIE suggesting cardiovascular system responds to ANS fluctuations during changing exercise intensity.

New and Noteworthy

This novel study analyzed beat -to-beat blood pressure variability during high intensity interval exercise (HIIE) in young healthy adults. We found that blood pressure variability was highest during active recovery compared to resting or high intensity exercise. Moreover, variability increased during HIIE but returned to resting post-exercise. These findings provide valuable insights into the blood pressure and ANS responses to HIIE, contributing to our understanding of their impact on overall cardiovascular health in young adults.

Noninvasive characterization of peripheral sympathetic activation across sensory stimuli using a peripheral arterial stiffness index

Introduction: The peripheral arterial stiffness index has been proposed and validated as a noninvasive measure quantifying stimulus intensity based on amplitude changes induced by sympathetic innervation of vascular tone. However, its temporal response characteristics remain unclear, thus hindering continuous and accurate monitoring of the dynamic process of sympathetic activation. This paper presents a study aimed at modeling the transient response of the index across sensory stimuli to characterize the corresponding peripheral sympathetic activation. Methods: The index was measured using a continuous arterial pressure monitor and a pulse oximeter during experiments with local pain and local cooling stimuli designed to elicit different patterns of sympathetic activation. The corresponding response of the index was modeled to clarify its transient response characteristics across stimuli. Results: The constructed transfer function accurately depicted the transient response of the index to local pain and local cooling stimuli (Fit percentage: 78.4% ± 11.00% and 79.92% ± 8.79%). Differences in dead time (1.17 ± 0.67 and 0.99 ± 0.56 s, p = 0.082), peak time (2.89 ± 0.81 and 2.64 ± 0.68 s, p = 0.006), and rise time (1.81 ± 0.50 and 1.65 ± 0.48 s, p = 0.020) revealed different response patterns of the index across stimuli. The index also accurately characterized similar vasomotor velocities at different normalized peak amplitudes (0.19 ± 0.16 and 0.16 ± 0.19 a.u., p = 0.007). Discussion: Our findings flesh out the characterization of peripheral arterial stiffness index responses to different sensory stimuli and demonstrate its validity in characterizing peripheral sympathetic activation. This study valorizes a noninvasive method to characterize peripheral sympathetic activation, with the potential to use this index to continuously and accurately track sympathetic activators.

Novel Pulse Waveform Index by Ambulatory Blood Pressure Monitoring and Cardiac Function: A Pilot Study

Background

A simple ambulatory measure of cardiac function could be helpful for monitoring heart failure patients.

Objectives

The purpose of this paper was to determine whether a novel pulse waveform analysis using data obtained by our developed multisensor-ambulatory blood pressure monitoring (ABPM) device, the 'Sf/Am' ratio, is associated with echocardiographic left ventricular ejection fraction (LVEF).

Methods

Multisensor-ABPM was conducted twice at baseline in 20 heart failure (HF) patients with HF-reduced LVEF or HF-preserved LVEF (median age 66 years, male 65%) and over a 6- to 12-month follow-up after patient-tailored treatment. We assessed the changes in the pulse waveform index Sf/Am and LVEF that occurred between the baseline and follow-up. The Sf/Am consists of the area of the ejection part in the square forward wave (Sf) and the amplitude of the measured wave (Am). We divided the patients into the recovered (n = 11) and not-recovered (n = 9) groups defined by a ≥10% increase in LVEF.

Results

Although the ambulatory BP levels and variabilities did not change in either group, the Sf/Am increased significantly in the recovered group (baseline 21.4 ± 4.5; follow-up, 25.6 ± 3.7, P = 0.004). The not-recovered group showed no difference between the baseline and follow-up. The follow-up/baseline Sf/Am ratio was significantly associated with the LVEF ratio (r = 0.469, P = 0.037). The Sf/Am was significantly correlated with the LVEF in overall measurements (n = 40, r = 0.491, P = 0.001).

Conclusions

These results demonstrated that a novel noninvasive pulse waveform index, the Sf/Am measured by multisensor-ABPM is associated with LVEF. The Sf/Am may be useful for estimating cardiac function.

Smartphone-Based versus Non-Invasive Automatic Oscillometric Brachial Cuff Blood Pressure Measurements: A Prospective Method Comparison Volunteer Study

Introduction: Mobile health diagnostics have demonstrated effectiveness in detecting and managing chronic diseases. This method comparison study aims to assess the accuracy and precision of the previously evaluated OptiBP™ technology over a four-week study period. This device uses optical signals recorded by placing a patient's fingertip on a smartphone's camera to estimate blood pressure (BP). Methods: In adult participants without cardiac arrhythmias and minimal interarm blood pressure difference (systolic arterial pressure (SAP) < 15 mmHg or diastolic arterial pressure (DAP) < 10 mmHg), three pairs of 30 s BP measurements with the OptiBP™ (test method) were simultaneously compared using three pairs of measurements with the non-invasive oscillometric brachial cuff (reference method) on the opposite arm over a period of four consecutive weeks at a rate of two measurements per week (one in the morning and one in the afternoon). The agreement of BP values between the two technologies was analyzed using Bland-Altman and error grid analyses. The performance of the smartphone application was investigated using the International Organization for Standardization (ISO) definitions, which require the bias ± standard deviation (SD) between two technologies to be lower than 5 ± 8 mmHg. Results: Among the 65 eligible volunteers, 53 participants had adequate OptiBP™ BP values. In 12 patients, no OptiBP™ BP could be measured due to inadequate signals. Only nine participants had known chronic arterial hypertension and 76% of those patients were treated. The mean bias ± SD between both technologies was -1.4 mmHg ± 10.1 mmHg for systolic arterial pressure (SAP), 0.2 mmHg ± 6.5 mmHg for diastolic arterial pressure (DAP) and -0.5 mmHg ± 6.9 mmHg for mean arterial pressure (MAP). Error grid analyses indicated that 100% of the pairs of BP measurements were located in zones A (no risk) and B (low risk). Conclusions: In a cohort of volunteers, we observed an acceptable agreement between BP values obtained with the OptiBPTM and those obtained with the reference method over a four-week period. The OptiBPTM fulfills the ISO standards for MAP and DAP (but not SAP). The error grid analyses showed that 100% measurements were located in risk zones A and B. Despite the need for some technological improvements, this application may become an important tool to measure BP in the future.

Variability in exercise is linked to improved age-related dysfunctions: A potential role for the constrained-disorder principle-based second-generation artificial intelligence system

Objective: Regular physical activity (PA) promotes mental and physical health. Nevertheless, inactivity is a worldwide pandemic, and methods to augment exercise benefits are required. The constrained disorder principle (CDP) characterizes biological systems based on their inherent variability. We aimed to investigate the association between intra-individual variability in PA and disability among non-athlete adults. Methods: In this retrospective analysis of the longitudinal SHARE survey, we included non-disabled adults aged >50 with at least six visits over 14 years. Self-reported PA frequency was documented bi- to triennially. Low PA intensity was defined as vigorous PA frequency less than once a week. Stable PA was described as an unchanged PA intensity in all consecutive middle observations. The primary outcome was defined as a physical limitation in everyday activities at the end of the survey. Secondary outcomes were cognitive functions, including short-term memory, long-term memory, and verbal fluency. Results: The study included 2,049 non-disabled adults with a mean age of 53 and 49.1% women. In the initially high PA intensity group, variability in PA was associated with increased physical disability prevalence (23.3% vs. 33.2%, stable vs. unstable PA ; P<0.01; adjusted P<0.01). In the initially low PA intensity group, variability was associated with a reduced physical disability (45.6% vs. 33.3%, stable vs. unstable PA ; P=0.02; adjusted P=0.03). There were no statistically significant differences in cognitive parameters between the groups. Among individuals with the same low PA intensity at the beginning and end of follow-up, variability was associated with reduced physical disability (56.9% vs. 36.5%, stable vs. unstable PA ; P=0.02; adjusted P=0.04) and improved short-term memory (score change: -0.28 vs. +0.29, stable vs. unstable PA ; P=0.05). Conclusion: Incorporating variability into PA regimens of inactive adults may enhance their physical and cognitive benefits.

European Society of Hypertension recommendations for the validation of cuffless blood pressure measuring devices: European Society of Hypertension Working Group on Blood Pressure Monitoring and Cardiovascular Variability

BACKGROUND

There is intense effort to develop cuffless blood pressure (BP) measuring devices, and several are already on the market claiming that they provide accurate measurements. These devices are heterogeneous in measurement principle, intended use, functions, and calibration, and have special accuracy issues requiring different validation than classic cuff BP monitors. To date, there are no generally accepted protocols for their validation to ensure adequate accuracy for clinical use.

OBJECTIVE

This statement by the European Society of Hypertension (ESH) Working Group on BP Monitoring and Cardiovascular Variability recommends procedures for validating intermittent cuffless BP devices (providing measurements every >30 sec and usually 30-60 min, or upon user initiation), which are most common.

VALIDATION PROCEDURES

Six validation tests are defined for evaluating different aspects of intermittent cuffless devices: static test (absolute BP accuracy); device position test (hydrostatic pressure effect robustness); treatment test (BP decrease accuracy); awake/asleep test (BP change accuracy); exercise test (BP increase accuracy); and recalibration test (cuff calibration stability over time). Not all these tests are required for a given device. The necessary tests depend on whether the device requires individual user calibration, measures automatically or manually, and takes measurements in more than one position.

CONCLUSION

The validation of cuffless BP devices is complex and needs to be tailored according to their functions and calibration. These ESH recommendations present specific, clinically meaningful, and pragmatic validation procedures for different types of intermittent cuffless devices to ensure that only accurate devices will be used in the evaluation and management of hypertension.

Comparison of Ambulatory and Home Blood Pressure Variability for Cardiovascular Prognosis and Biomarkers

BACKGROUND

Although blood pressure variability (BPV) is reported to be associated with cardiovascular prognoses, it has not been established whether ambulatory BPV (ABPV; ie, short-term 24-hour BPV) or home BPV (HBPV; day-to-day BPV) is a superior clinical marker.

METHODS

We analyzed the associations of ABPV and HBPV with cardiovascular prognoses and biomarkers in 1314 hypertensive outpatients who underwent both home and ambulatory BP measurements in the J-HOP study (Japan Morning-Surge Home Blood Pressure). BPV was evaluated by the SD, coefficient of variation, and average real variability of the patients' 24-hour ambulatory and home systolic BP values.

RESULTS

During the median 7.0-year follow-up, 109 cardiovascular events occurred. All SD, coefficient of variation, and average real variability values of the HBPV were significantly associated with cardiovascular risk even after adjusting by average 24-hour ambulatory systolic BP and each ABPV value: 1 SD of hazard ratio (95% CI) for the SD, 1.36 (1.14-1.63); coefficient of variation, 1.38 (1.16-1.66); and average real variability 1.29 (1.10-1.51) of HBPV. The ABPV parameters did not exhibit comparable relationships. The cardiovascular risk spline curves showed a trend toward increased risks with increasing HBPV parameters. There were no differences between ABPV and HBPV in the relationships with B-type natriuretic peptide and the urine albumin-creatine ratio.

CONCLUSIONS

In this comparative analysis of ambulatory and home BP monitoring values in individuals with hypertension, ABPV was not significantly associated with cardiovascular prognosis adjusted by average BP level, and HBPV was suggested to have modest superiority in predicting cardiovascular prognosis compared with ABPV.

Arterial blood pressure waveform in liver transplant surgery possesses variability of morphology reflecting recipients' acuity and predicting short term outcomes

We investigated clinical information underneath the beat-to-beat fluctuation of the arterial blood pressure (ABP) waveform morphology. We proposed the Dynamical Diffusion Map algorithm (DDMap) to quantify the variability of morphology.  The underlying physiology could be the compensatory mechanisms involving complex interactions between various physiological mechanisms to regulate the cardiovascular system. As a liver transplant surgery contains distinct periods, we investigated its clinical behavior in different surgical steps. Our study used DDmap algorithm, based on unsupervised manifold learning, to obtain a quantitative index for the beat-to-beat variability of morphology. We examined the correlation between the variability of ABP morphology and disease acuity as indicated by Model for End-Stage Liver Disease (MELD) scores, the postoperative laboratory data, and 4 early allograft failure (EAF) scores. Among the 85 enrolled patients, the variability of morphology obtained during the presurgical phase was best correlated with MELD-Na scores. The neohepatic phase variability of morphology was associated with EAF scores as well as postoperative bilirubin levels, international normalized ratio, aspartate aminotransferase levels, and platelet count. Furthermore, variability of morphology presents more associations with the above clinical conditions than the common BP measures and their BP variability indices. The variability of morphology obtained during the presurgical phase is indicative of patient acuity, whereas those during the neohepatic phase are indicative of short-term surgical outcomes.

Home blood pressure-centered approach - from digital health to medical practice: HOPE Asia Network consensus statement 2023

Recent innovations in digital technology have enabled the simultaneous accumulation, and the linking and analysis of time-series big data relating to several factors that influence blood pressure (BP), including biological indicators, physical activity, and environmental information. Various approaches can be used to monitor BP: in the office/clinic; at home; 24-h ambulatory recording; or with wearable and cuffless devices. Of these, home BP monitoring is a reliable and convenient method, and is recommended for hypertension management by current national and international guidelines. This recommendation is based on evidence showing that home BP is an important predictor of cardiovascular, cerebrovascular and kidney disease in patients with hypertension. In addition, lifetime personalized health record (PHR)-based home BP with telemonitoring combined with co-interventions has been shown to lower BP more effectively than the traditional approach based on office BP. Thus, home BP represents a key metric for personalized anticipation medicine, from digital healthcare to digital medicine. This paper summarizes the latest evidence on home BP monitoring and proposes a Hypertension Cardiovascular Outcome Prevention and Evidence in Asia (HOPE Asia) Network consensus on a home BP-centered approach to the management of hypertension.

Development and Evaluation of Solid Dispersion-Based Sublingual Films of Nisoldipine

Nisoldipine (NIS) is a calcium channel blocker that exhibits poor bioavailability (~5%) due to low aqueous solubility and presystemic metabolism in the gut wall. In this context, the present work aimed to develop NIS solid dispersion (NISSD)-based sublingual films using solvent casting technique to improve the dissolution. Phase solubility studies indicated that Soluplus® was the most effective carrier for improving the aqueous solubility of NIS. NISSDs were initially developed using the solvent evaporation method. Fourier transform infrared spectrometric studies were found to display the characteristic vibrational bands related to C=O stretching and N-H deformation in NISSDs, proving the chemical integrity of the drug in NISSDs. Subsequently, bioadhesive sublingual films of NISSDs were formulated using solvent casting method, using hydroxypropyl methyl cellulose (HPMC) E5, E15, and hydroxy ethyl cellulose (HEC EF) as hydrophilic polymers and polyethylene glycol 400 (PEG 400) as plasticizer. The incorporation of NISSDs was found to produce clear films that displayed uniform content. The sublingual film of NISSDs composed of HPMC E5 (2% w/v), was found to display the least thickness (0.29 ± 0.02 mm), the highest folding endurance (168.66 ± 4.50 times), and good bioadhesion strength (12.73 ± 0.503 g/cm2). This film was found to rapidly disintegrate (28.66 ± 3.05 sec) and display near-complete drug release (94.24 ± 1.22) in 30 min. Incorporating NISSDs into rapidly bioadhesive sublingual films considerably improves drug dissolution. Overall, these research outcomes underscored the potential of rapidly dissolving bioadhesive sublingual films to evade gut metabolism and resolve the bioavailability issues associated with oral administration of NIS.

Changes in beat-to-beat blood pressure and pulse rate variability following stroke

Associations between cerebrovascular disease and impaired autonomic function and cerebrovascular reactivity have led to increased interest in variability of heart rate (HRV) and blood pressure (BPV) following stroke. In this study, beat-to-beat pulse rate variability (PRV) and BPV were measured in clinically stable stroke patients (6 ischemic, 2 hemorrhagic) at least one year after their last cerebrovascular event. Beat-to-beat blood pressure (BP) measurements were collected from subjects while resting in the sitting position for one hour. Compared with healthy controls, stroke patients exhibited significantly greater time-domain (standard deviation, coefficient of variation, average real variability) and normalized high-frequency BPV (all p < 0.05). Stroke patients also exhibited lower LF:HF ratios than control subjects (p = 0.003). No significant differences were observed in PRV between the two groups, suggesting that BPV may be a more sensitive biomarker of cerebrovascular function in long-term post-stroke patients. Given a paucity of existing literature investigating beat-to-beat BPV in clinically stable post-stroke patients long (> 1 year) after their cerebrovascular events, this pilot study can help inform future studies investigating the mechanisms and effects of BPV in stroke. Elucidating this physiology may facilitate long-term patient monitoring and pharmacological management to mitigate the risk for recurrent stroke.

Digital hypertension towards to the anticipation medicine

"Digital Hypertension" is a new research field proposed by the Japanese Society of Hypertension that integrates digital technology into hypertension management and proactively promotes research activities. This novel approach includes the development of new technologies for better BP management, such as sensors for detecting environmental factors that affect BP, information processing, and machine learning. To facilitate "Digital Hypertension," a more sophisticated BP monitoring system capable of measuring an individual's BP more frequently in various situations would be required. With the use of these technologies, hypertension management could shift from the current "dots" management based on office BP readings during clinic visits to a "line" management system based on seamless home BP or individual BP data taken by a wearable BP monitoring device. DTx is the innovation to change hypertension management from "dots" to "line", completely achieved by wearable BP.