Is blood pressure load associated, independently of blood pressure level, with target organ damage?

The utility of home blood pressure load in predicting average self-measured blood pressure

OBJECTIVES

Average values for self-measured blood pressure (SMBP) more accurately reflect a patient's risk of cardiovascular disease than do office measurements. Oftentimes, however, patients provide lists of individual home blood pressure (BP) measurements, and average values cannot be computed within the time constraints of a clinic visit. In contrast, the home BP load - defined as the proportion of BP values greater than a partition value (e.g., 130 mmHg) - can be easily calculated. We examined the utility of the BP load in predicting the mean SMBP and confirming elevated SMBP.

METHODS

Four hundred twenty untreated adults at least 30 years of age acquired SMBP data twice in the morning and twice in the evening over 10 days. The 'true' SMBP was defined as the mean of these 40 determinations.

RESULTS

Using all 10 days of BP data and a systolic BP threshold of 130 mmHg, the average SMBP associated with a home BP load of 0.50 was 130 mmHg, with a 95% prediction interval of 126-133 mmHg. True systolic SMBP was approximately 6 mmHg lower and higher at home BP loads of 0.25 and 0.75, respectively. There was a 90% probability that the true systolic SMBP was greater than 130 mmHg if the systolic home BP load was at least 0.60. Corresponding values for 3 days and 1 day of SMBP were at least 0.68 and at least 0.84, respectively.

CONCLUSION

Our analysis demonstrates that the home BP load can be used to estimate the average BP acquired on home monitoring and confirm elevated SMBP.

Time course of hypertension and myocardial dysfunction following anthracycline chemotherapy in pediatric patients

Background

Anthracyclines are associated with cardiac dysfunction. Little is known about the interplay of pre-existing hypertension and treatment response. We aimed to investigate the relationship between hypertension and the development of cancer therapy-related cardiac dysfunction (CTRCD) in pediatric patients treated with anthracycline chemotherapy.

Methods

Pediatric patients with cancer who received anthracycline chemotherapy from 2013 to 2021 were retrospectively included. Serial cardiac assessments were conducted during and after chemotherapy. The primary outcome was the development of CTRCD, classified as mild, moderate, or severe according to contemporary definitions.

Results

Among 190 patients undergoing anthracycline chemotherapy, 34 patients (17.9 %) had hypertension (24 patients Stage 1, and 10 patients Stage 2) at baseline evaluation. Patients underwent chemotherapy for a median of 234.4 days (interquartile range 127.8-690.3 days) and were subsequently followed up. Hypertension was frequent during follow-up 31.3 % (0-3 months), 15.8 % (3-6 months), 21.9 % (0.5-1 years), 24.7 % (1-2 years), 31.1 % (2-4 years) and 35.8 % (beyond 4 years) (P for trend < 0.001). Freedom from mild CTRCD at 5 years was 45.0 %, freedom from moderate CTRCD was 87.8 % at 5 years. Baseline hypertension did not increase the risk of mild (HR 0.77, 95 % CI: 0.41-1.42, P = 0.385) or moderate CTRCD (HR 0.62, 95 % CI: 0.14-2.72, P = 0.504). Patients with baseline hypertension showed different global longitudinal strain (P < 0.001) and LVEF (P < 0.001) patterns during follow-up.

Conclusions

Pediatric patients often develop CTRCD post-anthracycline chemotherapy. Those with pre-existing hypertension show a unique treatment response, despite no increased CTRCD risk, warranting further investigation.

Relation between blood pressure time in range and composite cardiovascular outcomes in patients with primary aldosteronism: a retrospective case study

PURPOSE

To investigate the association between blood pressure (BP) time in range (TIR) and composite cardiovascular outcomes in patients with primary aldosteronism (PA).

METHODS

Between January 2019 and December 2021, 47 patients with PA were recruited from the First Affiliated Hospital of Xiamen University. Twenty-four-hour ambulatory BP monitoring (ABPM) and cardiovascular outcomes were assessed in all patients during the first diagnosis of PA.

RESULTS

The mean age of the patients was 48.8 ± 11.4 years. Compared to PA without composite cardiovascular outcomes, the nighttime systolic BP TIR [31.2% (6.2%, 81.2%) vs. 11.5% (0.0%, 29.7%), p = 0.02] and defined daily dose (DDDs) of antihypertensive medication [2.0 (1.0, 2.8) vs. 1.0 (1.0, 2.0), p = 0.03] were lower in PA patients with composite cardiovascular outcomes, while higher glucose (5.0 ± 1.0 mmol/L vs. 5.9 ± 1.5 mmol/L) and prevalence of a history of alcohol intake was higher in PA patients with composite cardiovascular outcomes. There were no differences in age, sex, BMI, smoking, duration of hypertension, lipid levels, aldosteronism, clinic BP, 24-hour mean BP, daytime or nighttime BP, percentage of nocturnal SBP or DBP decline, 24-hour BP TIR, daytime BP TIR, or nighttime DBP TIR between the two groups. After adjusting for confounding factors, nighttime systolic BP TIR was significantly associated with composite cardiovascular outcomes (adjusted OR = 0.92 [95% CI 0.86, 0.99]) in multiple logistic regression analysis.

CONCLUSION

Nighttime systolic BP TIR was significantly associated with composite cardiovascular outcomes in patients with PA.

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.

[Ambulatory blood pressure monitoring, adult and pediatric population. A narrative review]

Hypertension has become a central risk factor for the development of cardiovascular disease, underscoring the importance of its accurate diagnosis. Numerous studies have established a close relationship between elevated systolic (SBP) and diastolic (DBP) blood pressure and an increased risk of cardiovascular event (CVE). Traditionally, blood pressure (BP) measurements performed in clinical settings have been the main method for diagnosing and assessing hypertension. However, in recent years, it has been recognized that BP measurements obtained outside the clinical setting, using self-monitoring blood pressure (SMBP) and ambulatory blood pressure monitoring (ABPM), offer a more realistic perspective of patients' daily lives and therefore provide more reliable results. Given the evolution of medical devices, diagnostic criteria, and the increasing relevance of certain components of ABPM in the prediction of adverse cardiovascular outcomes, a comprehensive update that is practical for daily clinical practice is required. The main objective of this article is to provide an updated review of ABPM, focusing on its importance in the evaluation of hypertension and its impact on public health in Colombia. In addition, it will discuss the implications of changes in diagnostic thresholds and provide concrete recommendations for the effective implementation of ABPM in clinical practice, allowing health professionals to make informed decisions and improve the care of their patients.

Cumulative blood pressure load and hypertensive nephropathy in Han Chinese hypertensive patients

The study aims to assess the relationship between cumulative blood pressure load (cBPL) and the risk of renal function decline in hypertensive patients and determine the blood pressure (BP) threshold required to prevent hypertensive nephropathy. A single-center prospective cohort study was conducted on hypertensive patients. The cBPL was defined as the proportion of area beyond variable BP cutoffs under ambulatory BP monitoring. Renal events were defined as > 25% (minor) or > 50% (major) decline of baseline estimated glomerular filtration rate (eGFR). Cox regression analysis was conducted between cBPL, other ambulatory BP parameters, and renal events. The results revealed a total of 436 Han Chinese hypertensive patients were eligible for enrollment. During an average follow-up period of 5.1 ± 3.3 years, a decline of > 25% and > 50% in eGFR was observed in 77 and eight participants, respectively. Cox regression analysis revealed that cSBPL140 (hazard ratio [HR], 1.102; 95% confidence interval [CI], 1.017-1.193; p = .017), cSBPL130 (HR, 1.076; 95% CI, 1.019-1.137; p = .008), and cSBPL120 (HR, 1.054; 95% CI, 1.010-1.099; p = .015) were independently associated with minor renal events. Similarly, cSBPL140 (HR, 1.228; 95% CI, 1.037-1.455; p = .017), cSBPL130 (HR, 1.189; 95% CI, 1.045-1.354; p = .009), and cSBPL120 (HR, 1.155; 95% CI, 1.039-1.285; p = .008) were independently associated with major renal events. In conclusion, cBPL is associated with renal function decline in hypertensive patients. Minimizing cBPL120 may decrease the risk of hypertensive nephropathy.

Race differences in ambulatory blood pressure monitoring parameters

BACKGROUND

Mean systolic and diastolic blood pressure (SBP and DBP) on ambulatory blood pressure (BP) monitoring (ABPM) are higher among Black compared with White adults. With 48 to 72 BP measurements obtained over 24 h, ABPM can generate parameters other than mean BP that are associated with increased risk for cardiovascular events. There are few data on race differences in ABPM parameters other than mean BP.

METHODS

To estimate differences between White and Black participants in ABPM parameters, we used pooled data from five US-based studies in which participants completed ABPM (n = 2580). We calculated measures of SBP and DBP level, including mean, load, peak, and measures of SBP and DBP variability, including average real variability (ARV) and peak increase.

RESULTS

There were 1513 (58.6%) Black and 1067 (41.4%) White participants with mean ages of 56.1 and 49.0 years, respectively. After multivariable adjustment, asleep SBP and DBP load were 5.7% (95% CI: 3.5-7.9%) and 2.7% (95% CI: 1.1-4.3%) higher, respectively, among Black compared with White participants. Black compared with White participants also had higher awake DBP ARV (0.3 [95%CI: 0.0-0.6] mmHg) and peak increase in DBP (0.4 [95% CI: 0.0-0.8] mmHg). There was no evidence of Black:White differences in awake measures of SBP level, asleep peak SBP or DBP, awake and asleep measures of SBP variability or asleep measures of DBP variability after multivariable adjustment.

CONCLUSION

Asleep SBP load, awake DBP ARV and peak increase in awake DBP were higher in Black compared to White participants, independent of mean BP on ABPM.

The Role of Blood Pressure Load in Ambulatory Blood Pressure Monitoring in Adults: A Literature Review of Current Evidence

BACKGROUND

The blood pressure load (BPL) is commonly defined as the percentage of readings in a 24-h ambulatory blood pressure monitoring (ABPM) study above a certain threshold, usually the upper normal limit. While it has been studied since the 1990s, the benefits of using this index have not been clearly demonstrated in adults. We present the first review on the associations of BPL with target organ damage (TOD) and clinical outcomes in adults, the major determinants for its role and utility in blood pressure measurement. We emphasize studies which evaluated whether BPL has added benefit to the average blood pressure indices on ABPM in predicting adverse outcomes.

METHODS

PubMed search for all English language papers mentioning ABPM and BPL.

RESULTS

While multiple studies assessed this question, the cumulative sample size is small. Whereas the associations of BPL with various TODs are evident, the available literature fails to demonstrate a clear and consistent added value for the BPL over the average blood pressure indices.

CONCLUSIONS

There is a need for prospective studies evaluating the role of BPL in blood pressure measurement. The current literature does not provide sound support for the use of BPL in clinical decisions.

Cardiovascular Risks of Hypertension: Lessons from Children with Chronic Kidney Disease

Hypertension is the most common complication of chronic kidney disease (CKD) in children, having a strong association with subsequential cardiovascular disease (CVD). In pediatric CKD, a considerable percentage of children with hypertension are undiagnosed or undertreated. Prior research has evaluated structural and functional markers of subclinical CVD and biomarkers in adults with CKD, while ideal biomarkers in pediatrics are still insufficiently studied. The ultimate goal of this review is to summarize what is currently known about state of hypertension, cardiovascular risk factors, and potential CVD markers/biomarkers in children with pre-dialysis CKD. We discuss omics-related biomarkers and the pathophysiologic processes of endothelial dysfunction, kidney injury, oxidative stress and inflammation that are classified by specific biomarkers. Moreover, we illustrate the existing challenges and highlight the paucity of pediatric CKD research to evaluate these CVD biomarkers for future clinical pediatric practice. Thus, achieving clinical utility of CVD biomarkers for use in pediatric CKD remains a significant challenge requiring additional efforts.

Cumulative Systolic Blood Pressure Load and Cardiovascular Risk in Patients With Diabetes

BACKGROUND

Standard measures of blood pressure (BP) do not account for both the magnitude and duration of exposure to elevated BP over time.

OBJECTIVES

The purpose of this study was to assess the association between cumulative systolic blood pressure (SBP) load and risk of cardiovascular events in patients with type 2 diabetes.

METHODS

A post hoc analysis of patients with type 2 diabetes followed by the ADVANCE-ON (Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation - Observational Study). Cumulative SBP load was defined as the area under curve for SBP values ≥130 mm Hg divided by the area under curve for all measured SBP values over a 24-month exposure period. HRs for the association between cumulative SBP load with major cardiovascular events and death were estimated using Cox models.

RESULTS

Over a median 7.6 years of follow-up, 1,469 major cardiovascular events, 1,615 deaths, and 660 cardiovascular deaths were observed in 9,338 participants. Each 1-SD increase in cumulative SBP load was associated with a 14% increase in major cardiovascular events (HR: 1.14; 95% CI: 1.09-1.20), 13% increase in all-cause mortality (HR: 1.13; 95% CI: 1.13-1.18), and 21% increase in cardiovascular death (HR: 1.21; 95% CI: 1.13-1.29). For the prediction of cardiovascular events and death, cumulative SBP load outperformed mean SBP, time-below-target SBP, and visit-to-visit SBP variability in terms of Akaike information criterion and net reclassification indexes.

CONCLUSIONS

Cumulative SBP load may provide better prediction of major cardiovascular events compared with traditional BP measures among patients with type 2 diabetes. These findings reinforce the importance of both the magnitude and duration of exposure to elevated SBP in assessing cardiovascular risk. (Action in Diabetes and Vascular Disease Preterax and Diamicron MR Controlled Evaluation Post Trial Observational Study [ADVANCE-ON]; NCT00949286).

Variation in paediatric 24-h ambulatory blood pressure monitoring interpretation by Canadian and UK physicians

Twenty-four-hour ambulatory blood pressure monitoring (ABPM) is widely accepted as a more accurate method for measurement of blood pressure (BP) compared to a single office-based measurement of BP. However, it is unclear how physicians interpret ABPM and make management decisions. This study's goal is to investigate variation in ABPM interpretation among paediatric nephrologists (Canada and UK) and paediatric cardiologists (Canada only) via an online survey. The survey content included baseline demographics, questions on the use and indications for ABPM, interpretation of results, and subsequent management decisions in various clinical scenarios. The survey was sent to 196 Canadian physicians, with 69 (35.2%) total responses. Thirty-five UK clinicians also completed the survey. Most respondents were >44 years old, were in practice for at least 11 years, and were university-based. There were substantial differences among clinicians in ABPM interpretation for isolated systolic, diastolic, and night-time hypertension. For example, only 53.1% of physicians would initiate or modify treatment in those with diastolic HTN in CKD. Further, even for the same abnormal ABPM parameter, the decision to start or alter treatment was influenced by the underlying medical condition. There is significant variation in clinical practice among physicians for interpretation and management of hypertension when using ABPM. Differences in guidelines among various jurisdictions, as well as knowledge gaps in the research on which guidelines are based, create ambiguity regarding ABPM interpretation and management decisions. A more protocolized approach and further insight into the reasoning behind the variation in physicians' interpretation may help to standardise practice.

Home Telemonitoring of Arterial Hypertension With Antihypertensive Treatment Titration: Protocol for a Randomized Controlled Prospective Trial (HOROSCOPE Study)

Background

Despite the availability of effective treatment, the control of hypertension remains insufficient. Telemonitoring in the management of hypertension would be an effective way to improve blood pressure control.

Objective

The aim of our study will be to evaluate the effects of telemonitoring with antihypertensive treatment titration on blood pressure control in Tunisian patients with hypertension.

Methods

Our trial will be a prospective, rater-blinded randomized controlled trial carried out with primary care physicians in the Sahel region of Tunisia. Patients will be eligible for enrollment if they are aged over 35 years, are newly diagnosed with hypertension, or are known to be poorly controlled on antihypertensive therapy. Participants will be randomly assigned in a 1:1 ratio to the telemonitoring arm or usual care arm. The telemonitoring arm will involve a weekly telephone call for the collection of the home blood pressure measurements, therapeutic education, and treatment compliance assessment as well as a monthly call for treatment titration and a side effect check. Randomization will be done via the use of an interactive web responsive system, and patients will be stratified by investigation center. Neither participants nor investigators will be masked to the group assignments. The primary outcome will be the change in mean 24-hour systolic blood pressure from baseline to the 6-month follow-up in the 2 groups. All randomized patients who attend the follow-up visit at 6 months and have no missing data for the primary outcome will be included in the analysis.

Results

Recruitment to the trial started in July 2020. The study was initiated with 17 primary care physicians. We expect the inclusion period to last for approximately 6 months. We expect to complete data collection by the end of 2021 and plan to disseminate the results subsequently.

Conclusions

The HOROSCOPE (Home Telemonitoring of Arterial Hypertension With Antihypertensive Treatment Titration: Randomized Controlled Prospective Trial) study will provide important new evidence that could shed some light on the feasibility and impact of telemonitoring and self-monitoring in a Tunisian population of patients with hypertension who consult primary care physicians.

Trial Registration

ClinicalTrials.gov NCT04607239; https://clinicaltrials.gov/ct2/show/NCT04607239

International Registered Report Identifier (IRRID)

DERR1-10.2196/26184

Blood Pressure Load: An Effective Indicator of Systemic Circulation Status in Individuals With Acute Altitude Sickness

Background: Acute high altitude (HA) exposure results in blood pressure (BP) variations in most subjects. Previous studies have demonstrated that higher BP is potentially correlated with acute mountain sickness (AMS). The BP load may be of clinical significance regarding systemic circulation status.

Objectives: This study aimed to examine HA-induced BP changes in patients with AMS compared to those in healthy subjects. Further, we provided clinical information about the relationship between variations in 24-h ambulatory parameters (BP level, BP variability, and BP load) and AMS.

Methods: Sixty-nine subjects were enrolled and all participants ascended Litang (4,100 m above sea level). They were monitored using a 24-h ambulatory blood pressure device and underwent echocardiography within 24 h of altitude exposure. The 2018 Lake Louise questionnaire was used to evaluate AMS.

Results: The AMS group comprised more women than men [15 (65.2%) vs. 13 (28.3%), P < 0.001] and fewer smokers [4 (17.4%) vs. 23 (50.0%), P = 0.009]. The AMS group exhibited significant increases in 24-h BP compared to the non-AMS group (24-h SBP variation: 10.52 ± 6.48 vs. 6.03 ± 9.27 mmHg, P = 0.041; 24-h DBP variation: 8.70 ± 4.57 vs. 5.03 ± 4.98 mmHg, P = 0.004). The variation of mean 24-h cBPL (cumulative BP load) (mean 24-h cSBPL: 10.58 ± 10.99 vs. 4.02 ± 10.58, P = 0.016; 24-h mean cDBPL: 6.03 ± 5.87 vs. 2.89 ± 4.99, P = 0.034) was also obviously higher in AMS subjects than in non-AMS subjects after HA exposure. 24-h mean cSBPL variation (OR = 1.07, P = 0.024) and 24-h mean cDBPL variation (OR = 1.14, P = 0.034) were independent risk factors of AMS. Moreover, variation of 24-h mean cSBPL showed a good correlation with AMS score (R = 0.504, P < 0.001).

Conclusions: Our study demonstrated that patients with AMS had higher BP and BP load changes after altitude exposure than healthy subjects. Excessive BP load variations were associated with AMS. Thus, BP load could be an effective indicator regarding systemic circulation status of AMS.

The Correlation Between ABPM Parameters and Left Ventricular Hypertrophy in Pediatric Essential Hypertension

OBJECTIVE

To explore the association of dipping pattern and blood pressure load with left ventricular hypertrophy (LVH) in pediatric essential hypertension.

MATERIALS AND METHODS

Through an echocardiography monitor and an ambulatory blood pressure monitor of 425 children and adolescents diagnosed with essential hypertension with no treatment received, we identified 140 cases of LVH. Grouping patients according to LVH (LVH, N = 140; n-LVH, N = 285), we further evaluated their ambulatory blood pressure monitoring (ABPM) parameters by comparing dipping patterns between groups. A multivariable logistic regression analysis was used to determine the effect of blood pressure load on LVH.

RESULTS

No significant difference was found in systolic or diastolic blood pressure dipping patterns between groups (P = 0.161, P = 0.139). However, compared to the n-LVH group, the LVH group presented significant elevated nighttime systolic blood pressure (SBP) (P < 0.05), while nighttime DBP remained stable (P = 0.391), resulting in higher daytime and nighttime SBP loads, higher nighttime DBP load, and higher 24-h SBP load (P < 0.05). Notably, our multivariable logistic regression has shown that this trend of 24-h SBP load acts independently as a critical risk factor for LVH.

CONCLUSION

Collectively, we observed a correlation between BP load and LVH in pediatric hypertension. Our data demonstrated that SBP load has a more significant weight in LVH progression, and 24-h SBP load, in particular, acts as a critical early prognostic parameter for LVH in pediatric hypertension.

Diagnosis of hypertension: Ambulatory pediatric American Heart Association/European Society of Hypertension versus blood pressure load thresholds

The agreement between the traditionally-used ambulatory blood pressure (ABP)-load thresholds in children and recently-recommended pediatric American Heart Association (AHA)/European Society of Hypertension (ESH) ABP thresholds for diagnosing ambulatory hypertension (AH), white coat hypertension (WCH), and masked hypertension (MH) has not been evaluated. In this cross-sectional study on 450 outpatient participants, the authors evaluated the agreement between previously used ABP-load 25%, 30%, 40%, 50% thresholds and the AHA/ESH thresholds for diagnosing AH, WCH, and MH. The American Academy of Pediatrics thresholds were used to diagnose office hypertension. The AHA threshold diagnosed ambulatory normotension/hypertension closest to ABP load 50% in 88% (95% CI 0.79, 0.96) participants (k 0.67, 95% CI 0.59, 0.75) and the ESH threshold diagnosed ambulatory normotension/hypertension closest to ABP load 40% in 86% (95% CI 0.77, 0.94) participants (k 0.66, 95% CI 0.59, 0.74). In contrast, the AHA/ESH thresholds had a relatively weaker agreement with ABP load 25%/30%. Therefore, the diagnosis of AH was closest between the AHA threshold and ABP load 50% (difference 3%, 95% CI -2.6%, 8.6%, p = .29) and between the ESH threshold and ABP load 40% (difference 4%, 95% CI -2.1%, 10.1%, p = .19) than between the AHA/ESH and ABP load 25%/30% thresholds. A similar agreement pattern persisted between the AHA/ESH and various ABP load thresholds for diagnosing WCH and MH. The AHA and ESH thresholds diagnosed AH, WCH, and MH closest to ABP load 40%/50% than ABP load 25%/30%. Future outcome-based studies are needed to guide the optimal use of these ABP thresholds in clinical practice.

Pediatric and Adult Ambulatory Blood Pressure Thresholds and Blood Pressure Load as Predictors of Left Ventricular Hypertrophy in Adolescents

[Figure: see text].

Practical application of ABPM in the pediatric nephrology clinic

The use of 24-h ABPM has become commonplace when diagnosing and managing hypertension in the pediatric population. Multiple clinical guidelines recommend ABPM as the preferred method for identifying white-coat hypertension, masked hypertension, and determining degree of blood pressure (BP) control. Accurate, timely diagnosis and optimal management are particularly important in certain populations, such as children with chronic kidney disease (CKD), diabetes, and other conditions with increased risk for cardiovascular disease. Understanding how best to utilize ABPM to achieve these goals is important for pediatric nephrologists and other hypertension specialists. This review will provide practical information on the equipment, application, interpretation, and documentation of ABPM in the specialty clinic.

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

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

Prognostic Value of Ambulatory Blood Pressure Load in Pediatric CKD

BACKGROUND AND OBJECTIVES

Elevated BP load is part of the criteria for ambulatory hypertension in pediatric but not adult guidelines. Our objectives were to determine the prevalence of isolated BP load elevation and associated risk with adverse outcomes in children with CKD, and to ascertain whether BP load offers risk discrimination independently or in conjunction with mean ambulatory BPs.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We studied 533 children in the CKD in Children (CKiD) Study to determine the prevalence of normotension, isolated BP load elevation (≥25% of all readings elevated but mean BP normal), and ambulatory hypertension. We examined the association between these categories of BP control and adverse outcomes (left ventricular hypertrophy [LVH] or ESKD). We used c-statistics to determine risk discrimination for outcomes by BP load used either independently or in conjunction with other BP parameters.

RESULTS

Overall, 23% of the cohort had isolated BP load elevation, but isolated BP load elevation was not statistically significantly associated with LVH in cross-section (odds ratio, 1.8; 95% CI, 0.8 to 4.2) or time to ESKD (hazard ratio, 1.2; 95% CI, 0.7 to 2.0). In unadjusted cross-sectional analysis, every 10% higher systolic BP load was associated with 1.1-times higher odds of LVH (95% CI, 1.0 to 1.3), but discrimination for LVH was poor (c=0.61). In unadjusted longitudinal analysis, every 10% higher systolic BP load was associated with a 1.2-times higher risk of ESKD (95% CI, 1.1 to 1.2), but discrimination for ESKD was also poor (c=0.60). After accounting for mean systolic BP, systolic BP load was not statistically significantly associated with either LVH or ESKD. Findings were similar with diastolic BP load.

CONCLUSIONS

BP load does not provide additive value in discriminating outcomes when used independently or in conjunction with mean systolic BP in children with CKD.

PODCAST

This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2020_03_11_CPOD10130819.mp3.

Changes in Ambulatory Blood Pressure Phenotype over Time in Children and Adolescents with Elevated Blood Pressures

OBJECTIVE

To determine the stability of ambulatory blood pressure monitoring (ABPM) over time in children referred for evaluation of elevated BPs and assess for factors predicting change.

STUDY DESIGN

This retrospective chart review conducted at Seattle Children's Hospital and University of Pittsburgh Medical Center Children's Hospital of Pittsburgh identified 124 children referred for elevated BPs with 2 ABPM studies at least 6 months apart. All subjects received lifestyle counseling. Subjects with secondary hypertension (HTN) or on antihypertensive medication were excluded. ABPM phenotype was classified using American Heart Association guidelines as showing normal BP, prehypertension, and HTN. Generalized linear mixed effect regression models were used to regress stable, improving, or worsening HTN outcomes at study follow-up on baseline BP index and load variables.

RESULTS

The median age of patients was 14.1 years (73% males) and the median interval between studies was 18 months. ABPM phenotype changed in 58 of 124 children, with 16% worsening and 31% improving. Older age was associated with persistence of HTN. Although not significant, decrease in body mass index z-score tracked with sustained normal ambulatory BPs.

CONCLUSIONS

Although the sample size is small, our study suggests ABPM phenotype shows variability over time. Further study is required to identify factors supporting risk for progression of ABPM phenotype over time.

Sex-specific association between serum immunoglobulin-M and brachial ankle pulse wave velocity in a Chinese population: Danyang Study

Emerging evidence supports a causal role for the immunoglobulin-M (IgM) as a protector of atherosclerosis. Since arterial stiffness is an index of subclinical atherosclerosis, we propose that IgM may play an important role in arterial stiffness. As the level of IgM differs between sexes, we investigate the sex-specific association of serum IgM with arterial stiffness in a Chinese population. The study subjects were recruited from Danyang in 2017. Using the Omron VP-1000 system, we measured brachial ankle pulse wave velocity (baPWV). Serum IgM concentration was measured by the immunoturbidimetry method. The 1030 study participants (mean age = 54.3 ± 9.0 years) included 407 men (39.5%), 428 hypertensive (41.6%), 80 diabetic (7.8%), and 512 arterial stiffness patients (49.7%). Serum IgM concentration was lower in men than women (0.97 vs. 1.26 μg/mL, P < 0.001) and negatively with alcohol intake (r = -0.11 in men and r = -0.07 in women, P ≤ 0.09). In multiple regression analyses, serum IgM concentration was negatively associated with baPWV in women (-0.82 m/s per 10-time increase in serum IgM concentration, P = 0.009) but not in men. In multivariable logistic regression analyses, elevated serum IgM concentration was associated with lower risks for arterial stiffness in women (OR = 0.26; 95% CI 0.08-0.82; P = 0.02) but not in men (OR = 0.66; 95% CI 0.17-2.62; P = 0.55). Categorical analyses produced similar results. Serum IgM is negatively associated with baPWV and accordingly associated with a lower risk of arterial stiffness in women.

Higher Frequency of Nocturnal Blood Pressure Dipping but Not Heart Rate Dipping in Inflammatory Bowel Disease

BACKGROUND

Masked hypertension (MHTN) and lack of nocturnal dipping in blood pressure (BP) have been linked to the state of inflammation.

AIMS

We aimed to assess the frequency of nocturnal patterns of BP and heart rate (HR) in patients with IBD.

METHODS

Sixty-three normotensive patients with confirmed IBD during remission and 63 healthy subjects were enrolled in a case-control study. All subjects were monitored for BP and HR over a period of 24 h under ambulatory setting. Means for BP and HR were calculated for nighttime and daytime periods. Daytime BP ≥ 135/85 mmHg, nighttime BP ≥ 120/70 mmHg, and 24-h average BP ≥ 130/80 mmHg were defined as MHTN. The main end points of this study were lack of >10% nocturnal decrease in the systolic BP (NDP-BP) and in HR (NDP-HR).

RESULTS

After exclusion of 8 patients with IBD from analysis, 55 patients and 63 control subjects (49% men) with a mean age of 37.5 ± 11.0 years were enrolled. NDP-BP was more common in the IBD group compared to controls (55 vs. 33%; P = 0.026). MHTN was detected in 24% of IBD patients compared to 8% among controls (P = 0.017). Meanwhile, NDP-HR was observed in 22% of the IBD patients and 30% of the control group (P = 0.402). IBD remained a significant predictor of NDP-BP (odds ratio 2.60, 95% confidence interval 1.19-5.51) following an adjustment for age and gender.

CONCLUSIONS

IBD is associated with higher frequency of NDP-BP and MHTN; however, nocturnal changes in HR were similar in both groups.

Insulin Resistance and Hypertension in Obese Youth With Sleep-Disordered Breathing Treated With Positive Airway Pressure: A Prospective Multicenter Study

STUDY OBJECTIVES

There is evidence that cardiometabolic disease associated with obesity and sleep-disordered breathing (SDB) in adults is present in youth. SDB is often treated with positive airway pressure (PAP) in youth with obesity. Our aims were to determine: (1) the prevalence of cardiometabolic disease and (2) whether PAP improves markers of cardiometabolic disease, in youth with obesity and newly diagnosed moderate-severe SDB.

METHODS

A prospective multicenter cohort study was conducted in youth (8 to 16 years old) with obesity, prescribed PAP therapy for newly diagnosed moderate-severe SDB. Assessments occurred at baseline and at 6 and 12 months. Outcomes included markers of insulin resistance (change in homeostasis model assessment of insulin resistance (HOMA-IR) at 6 months = primary outcome), hypertension (24-hour ambulatory/blood pressure) and inflammation (high-sensitivity C-reactive protein: hs-CRP).

RESULTS

Twenty-seven participants were enrolled. Of those with baseline testing available, 10/25 (40%) had HOMA-IR above the 97th percentile, 10/23 (44%) were hypertensive, 16/23 (70%) had loss of nocturnal blood pressure dip and hs-CRP was elevated in 16/27 (64%). There were no significant changes over time in markers of metabolic dysfunction or blood pressure, nor between PAP-adherent and non-adherent subgroups.

CONCLUSIONS

In youth with obesity and SDB, metabolic dysfunction and hypertension were highly prevalent. There were no statistically significant improvements in cardiometabolic markers 1 year after the prescription of PAP therapy, although clinically relevant improvements were seen in insulin resistance and systolic blood pressure load, important predictors of future risk of cardiovascular disease. Larger, longer-term studies are needed to determine whether PAP improves cardiometabolic outcomes in obese youth.

COMMENTARY

A commentary on this article appears in this issue on page 1025.

The relationship between 24-hour ambulatory blood pressure load and neutrophil-to-lymphocyte ratio

INTRODUCTION AND OBJECTIVE

The neutrophil-to-lymphocyte ratio (NLR) is established as a reliable marker of systemic inflammation. Low-grade inflammation has a key role in the pathogenesis and progression of hypertension (HTN). Blood pressure (BP) load, defined as the percentage of abnormally elevated BP readings, is a good marker of HTN severity. We aimed to evaluate the relationship between HTN severity and NLR using averaged ambulatory BP readings and BP load.

METHODS

A total of 300 patients with untreated essential HTN were included in this cross-sectional study. Patients were divided into quartiles according to NLR values (first: <1.55; second: 1.55-1.92; third: 1.92-2.48; and fourth: >2.48). Averaged ambulatory BP values and BP load were assessed for each quartile.

RESULTS

In the interquartile evaluation there were no differences between quartiles in terms of baseline demographic, clinical and echocardiographic characteristics (p>0.05). Daytime systolic BP (SBP), 24-hour diastolic BP (DBP), daytime DBP, daytime SBP load, 24-hour DBP load and daytime DBP load were found to be significantly higher in the upper two quartiles (p<0.05 for all). In correlation analysis, log NLR values were found to be positively correlated with 24-hour SBP, DBP, SBP load and DBP load (Pearson coefficients of 0.194, 0.197, 0.157 and 0.181, respectively; p<0.01 for all). In multivariate analysis, log NLR had an independent association with 24-hour SBP and DBP and 24-hour SBP and DBP load.

CONCLUSION

This study showed for the first time that increased NLR is independently associated with HTN severity in untreated essential HTN patients.

Treinamento aeróbio intenso promove redução da pressão arterial em hipertensos

INTRODUÇÃO: O treinamento físico promove importantes respostas adaptativas no organismo que diminuem a morbidade e a mortalidade em hipertensos. Entretanto, são poucos os estudos que avaliaram a resposta pressórica do treinamento aeróbio de diferentes intensidades em hipertensos. Objetivo: Analisar os efeitos do treinamento físico aeróbio intenso com relação ao treinamento físico moderado sobre a pressão arterial ambulatorial em hipertensos.MÉTODOS: Participaram do estudo 32 hipertensos (48 ± 9 anos) randomizados como: grupo de treinamento aeróbio de intensidade moderada (IM), intensidade de 60-65% da frequência cardíaca de reserva, 40 minutos, três sessões por semana (n=12); exercício aeróbio de alta intensidade (AI), intensidade de 80% a 85% da frequência cardíaca de reserva (n=12), com a duração ajustada para atingir o mesmo gasto energético que a IM e um grupo controle (GC) sem exercícios (n=10). Nos três grupos foram avaliadas variáveis da monitorização ambulatorial da pressão arterial de 24 horas (MAPA) antes e após as oito semanas de intervenção.RESULTADOS: Após a intervenção a pressão arterial sistólica (PAS) da vigília reduziu 10,1 mmHg (p=0,024) em AI e 9,7 mmHg (p=0,035) em IM e a pressão arterial diastólica (PAD) da vigília reduziu 12,3 mmHg (p=0,002) em AI e 8,4 mmHg (p<0,001) em IM. A PAS do sono reduziu 9,5 mmHg (p=0,004) apenas em AI e 9,8 mmHg (p=0,005) em IM. A PAD do sono reduziu 8,2 mmHg (p=0,006) em AI e 4,8 mmHg (p<0,007) em IM. As cargas pressóricas sistólicas e diastólicas da vigília e do sono reduziram-se significativamente apenas em AI.CONCLUSÃO: Treinamento físico aeróbio moderado e intenso com duração equalizada pelo gasto calórico tem efeito hipotensor semelhante em hipertensos. A carga pressórica reduziu apenas na AI, sendo assim intensidade-dependente.

Nighttime Systolic Blood-Pressure Load Is Correlated with Target-Organ Damage Independent of Ambulatory Blood-Pressure Level in Patients with Non-Diabetic Chronic Kidney Disease

Background

The impacts of blood pressure (BP) load on target-organ damage in patients with chronic kidney disease (CKD) are largely unclear. We examined whether BP load is correlated with target-organ damage (TOD) in Chinese CKD patients independent of BP level.

Methods

We recruited 1219 CKD patients admitted to our hospital division in this cross-sectional study. The TOD were measured by estimated glomerular filtration rate (eGFR), proteinuria, left ventricular mass index (LVMI) and carotid intima-media thickness (cIMT) in this study. Univariate and multivariate linear analyses were used to evaluate the relationship between systolic blood pressure (SBP) load, diastolic blood pressure (DBP) load and these renal, cardiovascular parameters.

Results

In multivariable-adjusted models, BP load and ambulatory BP levels both independently correlated with LVMI, eGFR and proteinuria in all groups of CKD patients (p<0.05), 24-h SBP correlated with cIMT only in non-diabetic CKD patients without hypertension (p<0.05), while nighttime SBP load was associated with cIMT only in non-diabetic CKD patients (p<0.05). Furthermore, nighttime SBP load additionally increased coefficient of determination (R²) and correlated with LVMI, proteinuria in non-diabetic CKD patients without hypertension (R² = 0.034, P<0.001 and R² = 0.012, P = 0.006 respectively) and LVMI, cIMT, eGFR in non-diabetic CKD patients with hypertension (R²>0.008, P<0.05) in multivariable-adjusted model which already including the 24-h BP. BP load did not refine this correlation based on the 24-h BP level in diabetic CKD patients.

Conclusion

Night-time SBP load was correlated with TOD in patients with non-diabetic chronic kidney disease independent of BP level.

Ambulatory blood pressure and blood pressure load responses to low sodium intervention in Han Chinese population

We aimed to illustrate ambulatory blood pressure monitoring parameters responses to low sodium intake and their differences between salt-sensitive and non-salt-sensitive individuals. A total of 186 participants were included in this analysis. Twenty-four hour, day-time and night-time blood pressure (BP) and BP load decreased during low sodium intervention, especially in salt-sensitive (SS) group. After multivariable adjustment, 24-h systolic BP, diastolic BP, mean arterial pressure and BP load responses to low sodium intervention of SS individuals were more pronounced than those of non-salt-sensitive individuals. Thus, reducing salt intake is potentially needed for the prevention of hypertension, especially in SS individuals.

Clinical utility of ambulatory blood pressure monitoring in the management of hypertension

Accurate blood pressure (BP) measurement is essential for the diagnosis, monitoring and management of hypertension. However, conventional office-based BP readings have several limitations that include a low reproducibility, the white-coat effect and the existence of masked hypertension. These limitations can be addressed through the use of ambulatory BP monitoring. Because ambulatory monitoring provides measurements at specific time intervals throughout a 24-hour period, this technique represents a better picture of the normal fluctuations in BP levels associated with daily activities and sleep. In addition, end-organ damage associated with hypertension is more closely related to ambulatory BP than office BP measurements and ambulatory BP profile give better prediction of clinical outcome than conventional BP measurements.

Comparison of 44-hour and fixed 24-hour ambulatory blood pressure monitoring in dialysis patients

The two most commonly used strategies to evaluate dialysis patients' blood pressure (BP) level are 44-hour and 24-hour ambulatory blood pressure monitoring (ABPM). The objective of this study was to find an appropriate 24-hour period that correlated well with the 44-hour BP level and determine the differences between these strategies. In a group of 51 dialysis patients, the authors performed 44-hour ABPM and extracted data for a fixed 24-hour ABPM. The fixed 24-hour ABPM started at 6 am on the nondialysis day. A strong correlation was found between all parameters of 44-hour and the fixed 24-hour ABPM, with paired sample t test showing only small magnitude changes in a few parameters. Both 24-hour ABPM and 44-hour ABPM were superior to clinic BP in predicting left ventricular mass index (LVMI) by multiple regression analysis. It was found that 44-hour ambulatory arterial stiffness index (AASI), but not 24-hour AASI, had a positive association with LVMI (r=0.328, P=.021). However, after adjustment for 44-hour systolic blood pressure, this association disappeared. Fixed 24-hour ABPM is a good surrogate of 44-hour ABPM to some extent, while 44-hour ABPM can provide more accurate and detailed information.