Risk Stratification by Cross-Classification of Central and Brachial Systolic Blood Pressure

Predictive role of triglyceride-glucose index and HOMA index on development of arterial stiffening in non-diabetic men

BACKGROUND AND AIMS

Insulin resistance (IR) is a major risk factor for cardiovascular disease. Recently, a novel index (triglyceride-glucose index-TyG) has been proposed as a surrogate marker of IR and a better expression of IR than the Homeostatic Model Assessment of IR (HOMA-IR) index. Few and heterogeneous data are so far available on the relationship between vascular damage and this novel index. Therefore, we aimed to estimate the predictive role of TyG, in comparison with the HOMA-IR, on the development of arterial stiffening (AS), defined as a pulse pressure>60 mmHg, in an 8-year follow-up observation of a sample of non-diabetic adult men (the Olivetti Heart Study).

METHODS AND RESULTS

The analysis included 527 non-diabetic men, with normal arterial elasticity at baseline and not on antihypertensive or hypolipidemic treatment. TyG was significantly greater in those who developed AS than those who did not (p = 0.006). On the contrary, the HOMA-IR index was not different between the two groups (p = 0.24). Similar trends were shown by logistic regression analysis adjusting for main confounders. After the stratification by the optimal cut-off point, values of TyG >4.70 were significantly associated with the development of AS, also after adjustment for main confounders. On the contrary, the HOMA-IR index >1.90 was not associated with the risk of AS development in multivariate models.

CONCLUSION

The results of this study indicate a predictive role of TyG on AS, independently of the main potential confounders. Moreover, the predictive power of TyG seems to be greater than that of the HOMA-IR index.

Differences between brachial and aortic blood pressure in adolescence and their implications for diagnosis of hypertension

OBJECTIVES

Blood pressure (BP) is the leading global cause of mortality, and its prevalence is increasing in children and adolescents. Aortic BP is lower than brachial BP in adults. We aimed to assess the extent of this difference and its impact on the diagnosis of hypertension among adolescents.

METHODS

We used data from 3850 participants from a UK cohort of births in the early 1990s in the Southwest of England, who attended their ∼17-year follow-up and had valid measures of brachial and aortic BP at that clinic [mean (SD) age 17.8 (0.4) years, 66% female individuals]. Data are presented as mean differences [95% prediction intervals] for both sexes.

RESULTS

Aortic systolic BP (SBP) was lower than brachial SBP [male, -22.3 (-31.2, -13.3) mmHg; female, -17.8 (-25.5, -10.0) mmHg]. Differences between aortic and brachial diastolic BP (DBP) were minimal. Based on brachial BP measurements, 101 male individuals (6%) and 22 female individuals (1%) were classified as hypertensive. In contrast, only nine male individuals (<1%) and 14 female individuals (<1%) met the criteria for hypertension based on aortic BP, and the predictive value of brachial BP for aortic hypertension was poor (positive-predictive value = 13.8%). Participants with aortic hypertension had a higher left ventricular mass index than those with brachial hypertension.

CONCLUSION

Brachial BP substantially overestimates aortic BP in adolescents because of marked aortic-to-brachial pulse pressure amplification. The use of brachial BP measurement may result in an overdiagnosis of hypertension during screening in adolescence.

Association of cardiovascular events with central systolic blood pressure: A systemic review and meta-analysis

Central blood pressure confers cardiovascular risk prediction ability, but whether the association between central systolic blood pressure (cSBP) and cardiovascular endpoints is independent of peripheral systolic blood pressure (pSBP) remains controversial. This systematic review and meta-analysis aim to investigate the associations between cSBP and cardiovascular endpoints in models including and excluding pSBP, respectively. Observational studies assessing the risk of composite cardiovascular endpoints with baseline cSBP were searched in PubMed, Embase, Scopus, Web of Science, and Cochrane Library to May 31, 2022. Risk of bias was assessed by the Newcastle-Ottawa Quality Assessment Scale, and random-effects models were used to pool estimates. Finally, 48 200 participants from 19 studies with a mean age of 59.0 ± 6.9 years were included. Per 10 mmHg increase of cSBP was associated with higher risk of composite cardiovascular outcomes (risk ratio [RR]: 1.14 [95%CI 1.08-1.19]) and cardiovascular death (RR: 1.18 [95%CI 1.08-1.30]), and the associations still existed after adjusting for pSBP (RR: 1.13 [95%CI 1.05-1.21] for composite cardiovascular endpoints; RR: 1.25 [95%CI 1.09-1.43] for cardiovascular death). In pSBP-unadjusted studies, increased cSBP was also associated with higher risk of all-cause mortality and stroke, but not in the pSBP-adjusted studies. Both cSBP and pSBP were similarly significantly associated with composite cardiovascular endpoints in models containing them separately and simultaneously. cSBP was significantly associated with cardiovascular events, independently of pSBP. Central or peripheral SBP could supplement cardiovascular risk assessment besides each other.

Rationale for the Inclusion of β-Blockers Among Major Antihypertensive Drugs in the 2023 European Society of Hypertension Guidelines

We address the reasons why, unlike other guidelines, in the 2023 guidelines of the European Society of Hypertension β-blockers (BBs) have been regarded as major drugs for the treatment of hypertension, at the same level as diuretics, calcium channel blockers, and blockers of the renin-angiotensin system. We argue that BBs, (1) reduce blood pressure (the main factor responsible for treatment-related protection) not less than other drugs, (2) reduce pooled cardiovascular outcomes and mortality in placebo-controlled trials, in which there has also been a sizeable reduction of all major cause-specific cardiovascular outcomes, (3) have been associated with a lower global cardiovascular protection in 2 but not in several other comparison trials, in which the protective effect of BBs versus the other major drugs has been similar or even greater, with a slightly smaller or no difference of global benefit in large trial meta-analyses and a similar protective effect when comparisons extend to BBs in combination versus other drug combinations. We mention the large number of cardiac and other comorbidities for which BBs are elective drugs, and we express criticism against the exclusion of BBs because of their lower protective effect against stroke in comparison trials, because, for still uncertain reasons, differences in protection against cause-specific events (stroke, heart failure, and coronary disease) have been reported for other major drugs. These partial data cannot replace global benefits as the main deciding factor for drug choice, also because in the general hypertensive population whether and which type of event might occur is unknown.

Age-dependent association of central blood pressure with cardiovascular outcomes: a cohort study involving 34 289 participants using the UK biobank

BACKGROUND

It remained unclear whether central blood pressures (BP) was more closely associated with cardiovascular disease (CVD) than brachial BP in different age groups.

OBJECTIVES

To investigate the age-stratified association of CVD with brachial and central BPs, and to evaluate corresponding improvement in model performance.

METHODS

This cohort study included 34 289 adults without baseline CVD from the UK Biobank dataset. Participants were categorized into middle-aged and older aged groups using the cut-off of age 65 years. The primary endpoint was a composite cardiovascular outcome consisting of cardiovascular mortality combined with nonfatal coronary events, heart failure and stroke. Multivariable-adjusted hazard ratios expressed CVD risks associated with BP increments of 10 mmHg. Akaike Information Criteria (AIC) was used for model comparisons.

RESULTS

In both groups, CVD events were associated with brachial or central SBP ( P  ≤ 0.002). Model fit was better for central SBP in middle-aged adults (AIC 4427.2 vs. 4429.5), but model fit was better for brachial SBP in older adults (AIC 10 246.7 vs. 10 247.1). Central SBP remained significantly associated to CVD events [hazard ratio = 1.05; 95% confidence interval (CI) 1.0-1.1] and improved model fit (AIC = 4426.6) after adjustment of brachial SBP only in the middle-aged adults. These results were consistent for pulse pressure (PP).

CONCLUSION

In middle-aged adults, higher central BPs were associated with greater risks of CVD events, even after adjusting for brachial BP indexes. For older adults, the superiority of central BP was not observed. Additional trials with adequate follow-up time will confirm the role of central BP in estimating CVD risk for middle-aged individuals.

Optimization and validation of a suprasystolic brachial cuff-based method for noninvasively estimating central aortic blood pressure

Clinical studies have extensively demonstrated that central aortic blood pressure (CABP) has greater clinical significance in comparison with peripheral blood pressure. Despite the existence of various techniques for noninvasively measuring CABP, the clinical applications of most techniques are hampered by the unsatisfactory accuracy or large variability in measurement errors. In this study, we proposed a new method for noninvasively estimating CABP with improved accuracy and reduced uncertain errors. The main idea was to optimize the estimation of the pulse wave transit time from the aorta to the occluded lumen of the brachial artery under a suprasystolic cuff by identifying and utilizing the characteristic information of the cuff oscillation wave, thereby improving the accuracy and stability of the CABP estimation algorithms under various physiological conditions. The method was firstly developed and verified based on large-scale virtual subject data (n = 800) generated by a computational model of the cardiovascular system coupled to a brachial cuff, and then validated with small-scale in vivo data (n = 34). The estimation errors for the aortic systolic pressure were -0.05 ± 0.63 mmHg in the test group of the virtual subjects and -1.09 ± 3.70 mmHg in the test group of the patients, both demonstrating a good performance. In particular, the estimation errors were found to be insensitive to variations in hemodynamic conditions and cardiovascular properties, manifesting the high robustness of the method. The method may have promising clinical applicability, although further validation studies with larger-scale clinical data remain necessary.

Invasively measured and estimated central blood pressure using the oscillometric algorithm Antares in patients with and without obesity

BACKGROUND

Obesity is a global health concern and risk factor for cardiovascular disease. The assessment of central blood pressure (cBP) has been shown to improve prediction of cardiovascular events. However, few studies have investigated the impact of obesity on cBP in adults, and invasive data on this issue are lacking. This study aimed to evaluate cBP differences between patients with and without obesity, identify cBP determinants, and evaluate the accuracy of the algorithm Antares for non-invasive cBP estimation.

METHODS

A total of 190 patients (25% female; 39% with BMI ≥30kg/m2; age: 67±12 years) undergoing elective cardiac catheterization were included. cBP was measured invasively and simultaneously estimated non-invasively using the custo screen 400 device with integrated Antares algorithm.

RESULTS

No significant cBP differences were found between obese and non-obese patients. However, females, especially those with obesity, had higher systolic cBP compared to males (P<0.05). Multiple regression analysis showed that brachial mean arterial pressure, pulse pressure, BMI, and heart rate predicted cBP significantly (adjusted R2 = 0.82, P<0.001). Estimated cBP correlated strongly with invasive cBP for systolic, mean arterial, and diastolic cBP (r = 0.74-0.93, P<0.001) and demonstrated excellent accuracy (mean difference <5 and SD <8 mmHg).

CONCLUSIONS

This study discovered no significant difference in cBP between obese and non-obese patients. However, it revealed higher cBP values in women, especially those with obesity, which requires further investigation. Additionally, the study highlights Antares' effectiveness in non-invasively determining cBP in obese individuals. This could improve the diagnosis and treatment of hypertension in this special patient population.

Vascular phenotypes in early hypertension

The study characterises vascular phenotypes of hypertensive patients utilising machine learning approaches. Newly diagnosed and treatment-naïve primary hypertensive patients without co-morbidities (aged 18-55, n = 73), and matched normotensive controls (n = 79) were recruited (NCT04015635). Blood pressure (BP) and BP variability were determined using 24 h ambulatory monitoring. Vascular phenotyping included SphygmoCor® measurement of pulse wave velocity (PWV), pulse wave analysis-derived augmentation index (PWA-AIx), and central BP; EndoPAT™-2000® provided reactive hyperaemia index (LnRHI) and augmentation index adjusted to heart rate of 75bpm. Ultrasound was used to analyse flow mediated dilatation and carotid intima-media thickness (CIMT). In addition to standard statistical methods to compare normotensive and hypertensive groups, machine learning techniques including biclustering explored hypertensive phenotypic subgroups. We report that arterial stiffness (PWV, PWA-AIx, EndoPAT-2000-derived AI@75) and central pressures were greater in incident hypertension than normotension. Endothelial function, percent nocturnal dip, and CIMT did not differ between groups. The vascular phenotype of white-coat hypertension imitated sustained hypertension with elevated arterial stiffness and central pressure; masked hypertension demonstrating values similar to normotension. Machine learning revealed three distinct hypertension clusters, representing 'arterially stiffened', 'vaso-protected', and 'non-dipper' patients. Key clustering features were nocturnal- and central-BP, percent dipping, and arterial stiffness measures. We conclude that untreated patients with primary hypertension demonstrate early arterial stiffening rather than endothelial dysfunction or CIMT alterations. Phenotypic heterogeneity in nocturnal and central BP, percent dipping, and arterial stiffness observed early in the course of disease may have implications for risk stratification.

Vascular ageing: moving from bench towards bedside

Prevention of cardiovascular disease (CVD) remains one of the largest public health challenges of our time. Identifying individuals at increased cardiovascular risk at an asymptomatic, sub-clinical stage is of paramount importance for minimizing disease progression as well as the substantial health and economic burden associated with overt CVD. Vascular ageing (VA) involves the deterioration in vascular structure and function over time and ultimately leads to damage in the heart, brain, kidney, and other organs. Vascular ageing encompasses the cumulative effect of all cardiovascular risk factors on the arterial wall over the life course and thus may help identify those at elevated cardiovascular risk, early in disease development. Although the concept of VA is gaining interest clinically, it is seldom measured in routine clinical practice due to lack of consensus on how to characterize VA as physiological vs. pathological and various practical issues. In this state-of-the-art review and as a network of scientists, clinicians, engineers, and industry partners with expertise in VA, we address six questions related to VA in an attempt to increase knowledge among the broader medical community and move the routine measurement of VA a little closer from bench towards bedside.

Hypertension in China: epidemiology and treatment initiatives

The past two to three decades have seen a steady increase in the prevalence of hypertension in China, largely owing to increased life expectancy and lifestyle changes (particularly among individuals aged 35-44 years). Data from the China hypertension survey conducted in 2012-2015 revealed a high prevalence of grade 3 hypertension (systolic blood pressure ≥180 mmHg and diastolic blood pressure ≥110 mmHg) in the general population, which increased with age to up to 5% among individuals aged ≥65 years. The risk profile of patients with hypertension in China has also been a subject of intense study in the past 30 years. Dietary sodium and potassium intake have remained largely the same in China in the past three decades, and salt substitution strategies seem to be effective in reducing blood pressure levels and the risk of cardiovascular events and death. However, the number of individuals with risk factors for hypertension and cardiovascular disease in general, such as physical inactivity and obesity, has increased dramatically in the same period. Moreover, even in patients diagnosed with hypertension, their disease is often poorly managed owing to a lack of patient education and poor treatment compliance. In this Review, we summarize the latest epidemiological data on hypertension in China, discuss the risk factors for hypertension that are specific to this population, and describe several ongoing nationwide hypertension control initiatives that target these risk factors, especially in the low-resource rural setting.

Brachial and central hypertension in relation to coronary stenosis in patients with coronary angiography

The clinical significance of central beyond brachial blood pressure (BP) remains unclear. In patients who underwent coronary angiography, the authors explored whether elevated central BP would be associated with coronary arterial disease (CAD) irrespective of the status of brachial hypertension. From March 2021 to April 2022, 335 patients (mean age 64.9 years, 69.9% men) hospitalized for suspected CAD or unstable angina were screened in an ongoing trial. CAD was defined if a coronary stenosis of ≥50%. According to the presence of brachial (non-invasive cuff systolic BP ≥140 mmHg or diastolic BP ≥90 mmHg) and central (invasive systolic BP ≥130 mmHg) hypertension, patients were cross-classified as isolated brachial hypertension (n = 23), isolated central hypertension (n = 93), and concordant normotension (n = 100) or hypertension (n = 119). In continuous analyses, both brachial and central systolic BPs were significantly related to CAD with similar standardized odds ratios (OR, 1.47 and 1.45, p < .05). While categorical analyses showed that patients with isolated central hypertension or concordant hypertension had a significantly higher prevalence of CAD and the Gensini score than those with concordant normotension. Multivariate-adjusted OR (95% confidence interval [CI]) for CAD was 2.24 (1.16 to 4.33, p = .009) for isolated central hypertension and 3.02 (1.58 to 5.78, p < .001) for concordant hypertension relative to concordant normotension. The corresponding OR (95% CI) of a high Gensini score was 2.40 (1.26-4.58) and 2.17 (1.19-3.96), respectively. In conclusion, regardless of the presence of brachial hypertension, elevated central BP was associated with the presence and severity of CAD, indicating that central hypertension is an important risk factor for coronary atherosclerosis.

CENtral blood pressure Targeting: a pragmatic RAndomized triaL in advanced Chronic Kidney Disease (CENTRAL-CKD): A Clinical Research Protocol

Background

Emerging data favor central blood pressure (BP) over brachial cuff BP to predict cardiovascular and kidney events, as central BP more closely relates to the true aortic BP. Considering that patients with advanced chronic kidney disease (CKD) are at high cardiovascular risk and can have unreliable brachial cuff BP measurements (due to high arterial stiffness), this population could benefit the most from hypertension management using central BP measurements.

Objective

To assess the feasibility and efficacy of targeting central BP as opposed to brachial BP in patients with CKD G4-5.

Design

Pragmatic multicentre double-blinded randomized controlled pilot trial.

Setting

Seven large academic advanced kidney care clinics across Canada.

Patients

A total of 116 adults with CKD G4-5 (estimated glomerular filtration rate [eGFR] < 30 mL/min) and brachial cuff systolic BP between 120 and 160 mm Hg. The key exclusion criteria are 1) ≥ 5 BP drugs, 2) recent acute kidney injury, myocardial infarction, stroke, heart failure or injurious fall, 3) previous kidney replacement therapy.

Methods

Double-blind randomization to a central or a brachial cuff systolic BP target (both < 130 mm Hg) as measured by a validated central BP device. The study duration is 12 months with follow-up visits every 2 to 4 months, based on local practice. All other aspects of CKD management are at the discretion of the attending nephrologist.

Outcomes

Primary Feasibility: Feasibility of a large-scale trial based on predefined components. Primary Efficacy: Carotid-femoral pulse wave velocity at 12 months. Others: Efficacy (eGFR decline, albuminuria, BP drugs, and quality of life); Events (major adverse cardiovascular events, CKD progression, hospitalization, mortality); Safety (low BP events and acute kidney injury).

Limitations

May be challenging to distinguish whether central BP is truly different from brachial BP to the point of significantly influencing treatment decisions. Therapeutic inertia may be a barrier to successfully completing a randomized trial in a population of CKD G4-5. These 2 aspects will be evaluated in the feasibility assessment of the trial.

Conclusion

This is the first trial to evaluate the feasibility and efficacy of using central BP to manage hypertension in advanced CKD, paving the way to a future large-scale trial.

Trial registration

clinicaltrials.gov (NCT05163158).

130/80 mmHg as a unifying hypertension threshold for office brachial, office central, and ambulatory daytime brachial blood pressure

The present study investigated the prognostic values for office brachial (OB), office central (OC), and ambulatory daytime brachial (AmDB) hypertension, as defined by a unifying threshold of 130/80 mmHg, and the incremental value of either OC or AmDB hypertension to OB hypertension. A total of 1219 community residents without receiving anti-hypertensive treatment (671 men and 548 women, aged ≥ 30 years old) from central Taiwan and Kinmen islands had OB, OC, and AmDB blood pressure measurements during a cardiovascular survey conducted in 1992-1993. OB hypertension, OC hypertension, and AmDB hypertension were all defined in retrospect at the threshold of 130/80 mmHg. They were followed up for nonfatal and fatal cardiovascular events until December 31, 2017, by linking the baseline database to the National Health Insurance Research dataset and the National Death Registry. During a follow-up of 25 612.5 person-years (Average event-free time: 21.0 years), there were 368 fatal and nonfatal cardiovascular events. In multivariable analyses, OB hypertension, OC hypertension, and AmDB hypertension had similar hazard ratios for cardiovascular events [2.03, 95% confidence interval: 1.47-2.80]; 1.92 (1.47-2.51); and 1.79 (1.41-2.29), respectively. Using OB normotension as the reference, either the concordant OB and OC hypertension [2.24 (1.61-3.12)], or the concordant OB and AmDB hypertension [2.52 (1.80-3.54)] was significantly associated with cardiovascular events. Moreover, OB hypertension plus AmDB normotension was also significantly associated with increased risk for cardiovascular events. We concluded that OB hypertension, OC hypertension, and AmDB hypertension defined by a unifying threshold of 130/80 mmHg may provide similar estimates of long-term risk for cardiovascular events. Cross-classification analyses suggest that addition of OC hypertension or AmDB hypertension may improve the prognostic value of OB hypertension.

The influence of body composition and fat distribution on circadian blood pressure rhythm and nocturnal mean arterial pressure dipping in patients with obesity

Loss of physiological nocturnal blood pressure (BP) decline is an independent predictor of cardiovascular risk and mortality. The aim of the study was to investigate the influence of body composition and fat distribution on 24-hour BP pattern and nocturnal dipping of mean arterial pressure (MAP) in patients with obesity. The study comprised 436 patients, 18 to 65 years old (306 women), with BMI ≥30 kg/m2. Body composition was assessed with dual-energy X-ray absorptiometry (DXA) and blood pressure was assessed by 24-hour BP monitoring. The prevalence of hypertension was 64.5% in patients with BMI <40 kg/m2 and increased to 78.7% in individuals with BMI ≥50 kg/m2 (p = 0.034). The whole-body DXA scans showed that the hypertensive patients were characterized by a greater lean body mass (LBM) and a higher abdominal-fat-to-total-fat-mass ratio (AbdF/FM), while the normotensive participants had greater fat mass, higher body fat percentage and more peripheral fat. Loss of physiological nocturnal MAP decline was diagnosed in 50.2% of the patients. The percentage of non-dippers increased significantly: from 38.2% in patients with BMI <40 kg/m2 to 50.3% in those with BMI 40.0-44.9 kg/m2, 59.0% in patients with BMI 45.0-49.9 kg/m2, 71.4% in those with BMI 50.0-54.9 kg/m2 and 83.3% in patients with BMI ≥55 kg/m2 (p = 0.032, p = 0.003, p<0.001, and p = 0.002 vs. BMI <40 kg/m2, respectively). The multivariable regression analysis showed that patients at the highest quartiles of body weight, BMI, LBM and AbdF/FM had significantly reduced nocturnal MAP dipping compared with patients at the lowest quartiles, respectively.

The Relationship of Vascular Aging to Reduced Cognitive Function: Pulsatile and Steady State Arterial Hemodynamics

Aortic stiffness increases with age and is a robust predictor of cerebrovascular events and cognitive decline including Alzheimer's disease and other forms of dementia. Recent clinical studies have investigated the association between proximal aortic stiffness and pulsatile energy transmission that has deleterious effects on the cerebrovascular network in order to identify potential therapeutic targets. Aging causes disproportionate stiffening of the aorta compared with the carotid arteries, reducing protective impedance mismatches at their interface, increasing the transmission of destructive pulsatile pressure and energy to the cerebral circulation, and leading to cerebral small vessel disease. Thus, aortic stiffening and high-flow pulsatility are associated with alterations in the microvasculature of the brain, vascular endothelial dysfunction, and white matter damage, which contribute to impaired memory function with advancing age. Previous studies have also shown that silent lacunar infarcts and white matter hyperintensities are strongly associated with arterial stiffness. More and more evidence suggests that vascular etiologies, including aortic stiffness, impedance match, and microvascular damage, are associated with cognitive impairment and the pathogenesis of dementia. The measurement of arterial flow and pressure can help understand pulsatile hemodynamics and its impact on vital organs. Interventions that reduce aortic stiffness, such as improvement of the living environment, management of risk factors, and innovation and development of novel drugs, may reduce the risk for dementia.

Central hypertension is a non-negligible cardiovascular risk factor

High blood pressure (BP) confers cardiovascular risk. However, the clinical value of central BP remains debatable. In this article, we aim to briefly review the prognosis, diagnosis, and treatment of central hypertension. Central and brachial BPs are closely correlated. In most prospective investigations, elevated central and peripheral BPs were similarly associated with adverse outcomes. Outcome-driven thresholds of the central systolic BP estimated by the type I device were on average 10 mmHg lower than their brachial counterparts. Cross-classification based on the central and brachial BPs identified that nearly 10% of patients had discrepancy in their status of central and brachial hypertension. Irrespective of the brachial BP status, central hypertension was associated with increased cardiovascular risk, highlighting the importance of central BP assessment in the management of hypertensive patients. Newer antihypertensive agents, such as renin-angiotensin-aldosterone system inhibitors and calcium channel blockers, were more efficacious than older agents in central BP reduction. Clinical trials are warranted to demonstrate whether controlling central hypertension with an optimized antihypertensive drug treatment will be beneficial beyond the control of brachial hypertension.