Association of visit-to-visit variability of systolic blood pressure with cardiovascular disease, chronic kidney disease and mortality in patients with hypertension

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. The present study derived BPV metrics from continuous beat-to-beat blood pressure monitoring data. Two sequential 7 min 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 = 0.87 and 0.82 respectively. Additionally, systolic average real variability was the most reliable metric in both the antihypertensive use group, and the no antihypertensive use group. In conclusion, beat-to-beat dispersion and sequence-based metrics of BPV can be reliably obtained in 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.

Vascular Calcification Exacerbates Abnormal Blood Pressure Variability in Chronic Kidney Disease: A "Two-Step" Study in Rats

INTRODUCTION

Vascular calcification (VC) is a common complication of chronic kidney disease (CKD) with poor cardiovascular prognosis. The aim of this study was to explore the impact of VC on blood pressure variability (BPV) in animal models of CKD.

METHODS

Two optimal modelling methods, adenine high-phosphorus (HP) diet + calcitriol and 5/6 nephrectomy (Nx) + HP diet + calcitriol, for CKD-VC were chosen from the first-step experiment for the next step. A total of 36 male Wistar rats were randomly assigned to the standard-chow, sham-operated, adenine, 5/6Nx, adenine-VC, and 5/6Nx-VC groups. Continuous blood pressure (BP) measurement using the BP-2000 animal noninvasive BP analyser was started at the 9th week for the standard-chow, adenine, and adenine-VC groups and at the 7th week for the sham-operated, 5/6Nx, and 5/6Nx-VC groups. BPV metrics (BPVs), including the difference between maximum and minimum values, standard deviation, coefficient of variation, average real variability, and residuals derived from the generalized linear model of BP, were calculated.

RESULTS

The first experiment showed that the use of calcitriol accelerated the progression of VC in CKD rats (the modelling period was shortened from 16 weeks to 4-8 weeks) and confirmed the occurrence of VC at weeks 8 and 6 in the adenine-VC and 5/6Nx-VC groups, respectively. In the second experiment, 13 of 20 hour-to-hour BPVs increased significantly with the development of CKD and VC. BPV differences among the standard-chow, adenine, and adenine-VC groups were mainly due to the differences between the standard-chow and adenine-VC groups (7 of 10 BPVs were significantly different), followed by the differences between the standard-chow and adenine groups (3 of 10). BPV differences among the sham-operated, 5/6Nx, and 5/6Nx-VC groups were caused by the differences between the 5/6Nx-VC and 5/6Nx groups (4 of 10) or the 5/6Nx-VC and sham-operated groups (3 of 10).

CONCLUSION

An increased BPV is observed in CKD rats, and VC further aggravates the abnormality of BPVs independent of CKD.

Short-term blood pressure variability and outcomes in non-dialysis chronic kidney disease

Background

Blood pressure variability (BPV) is associated with cardiovascular and all-cause mortality, and has been demonstrated in dialysis patients, but has been poorly studied and remains controversial in non-dialysis chronic kidney disease (CKD) patients. We investigated the effect of short-term BPV on prognosis in this population.

Methods

A total of 245 stage 1–4 CKD patients with 24-h ambulatory blood pressure recordings were recruited. BPV was evaluated by standard deviation, coefficient of variation, and variation independent of the mean, respectively. All subjects were followed up to the composite end-point event or until January 15, 2020. Patients were divided into two groups based on 24-h median variation independent of the mean, and demographics, laboratory indicators and echocardiogram results were compared. Logistic regression was used to analyze the risk factors for increased BPV. Multivariate Cox regression and Kaplan-Meier survival analysis were used to explore the relationship between BPV and renal prognosis and major cardiovascular events.

Results

The mean age was 42.07 ± 12.66 years, with 141 males (57.55%). Multivariate Logistic regression analysis showed that high BMI (OR 1.110, P = 0.017), hyperkalemia (OR 2.227, P = 0.040), increased left ventricular end-diastolic diameter (OR 1.103, P = 0.010) and hypertension (OR 2.525, P = 0.002) were independent risk factors for high BPV. Kaplan-Meier survival analysis showed that renal and cardiovascular outcomes were better in the low BPV group than in the high BPV group (P = 0.006; P = 0.002). After adjusting for age, sex and traditional kidney related risk factors, BPV were not independently associated with renal outcomes. High BPV (HR 4.662, P = 0.017) was the main independent risk factor for major cardiovascular events in CKD.

Conclusions

In non-dialysis CKD, short-term BPV was associated with major cardiovascular disease but not renal progression. BMI, hypertension, potassium balance, and left ventricular end-diastolic diameter influenced short-term BPV.

Visit-to-visit variability in blood pressure and kidney disease progression in IgA nephropathy

Background

The visit-to-visit variability (VVV) in blood pressure (BP) is an important risk factor for stroke and coronary heart disease and may also be associated with kidney damage and the development of chronic kidney disease (CKD). Data on the association between VVV in BP and the risk of CKD progression among patients with immunoglobulin A nephropathy (IgAN) are limited. We aimed to evaluate the relationships of VVV in BP with the progression of IgAN.

Methods

We assessed 1376 patients with IgAN at Peking University First Hospital. The main VVV in BP was expressed as the standard deviation (SD), coefficient of variation (CV) and average real variability (ARV). The associations of variability in BP with composite kidney disease progression events, defined as a 50% decline in estimated glomerular filtration rate (eGFR) and kidney failure, were examined using Cox models.

Results

During a median follow-up of 44.1 months (interquartile range 23.0–76.7), 247 (18.0%) patients experienced composite kidney disease progression events. With a higher SD in systolic BP (SBP) values, the risk of kidney disease progression events increased {hazard ratio [HR] 1.07 [95% confidence interval (CI) 1.03–1.11]; P < .001} after maximal adjustment, including baseline SBP and mean SBP during the first 12-month period. Using the first quartile of SD SBP values as the reference, the risk of composite kidney disease progression events was higher among patients with higher SD SBP values; the HR was 2.12 (95% CI 1.31–3.44) in the highest quartile (P for trend < .001). A similar trend could be observed when analysing the SD of diastolic BP, but the risk was not significantly increased. The associations were similar when analysed with the CV and ARV.

Conclusion

SBP variability was significantly associated with kidney disease progression in IgAN.

Blood pressure and its variability: classic and novel measurement techniques

Current hypertension guidelines recommend using the average values of several blood pressure (BP) readings obtained both in and out of the office for the diagnosis and management of hypertension. In-office BP measurement using an upper-arm cuff constitutes the evidence-based reference method for current BP classification and treatment targets. However, out-of-office BP evaluation using 24 h ambulatory or home BP monitoring is recommended by all major medical associations for obtaining further insights into the BP profile of an individual and how it relates to their daily activities. Importantly, the highly variable nature of office and out-of-office BP readings has been widely acknowledged, including the association of BP variability with cardiovascular outcomes. However, to date, the implications of BP variability on cardiovascular outcomes have largely been ignored, with limited application in clinical practice. Novel cuffless wearable technologies might provide a detailed assessment of the 24 h BP profile and behaviour over weeks or months. These devices offer many advantages for researchers and patients compared with traditional BP monitors, but their accuracy and utility remain uncertain. In this Review, we outline and compare conventional and novel methods and techniques for assessing average BP levels and BP variability, and reflect on the utility and potential of these methods for improving the treatment and management of patients with hypertension.

The most commonly available blood pressure (BP) monitoring devices are useful for capturing a snapshot BP value, but most have limited utility in measuring BP variability. In this Review, Schutte and colleagues outline the advantages and disadvantages of conventional and novel techniques to measure average BP levels and BP variability.

Although the dynamic nature of blood pressure (BP) is well-known, hypertension guidelines recommend using the average values of static BP readings (office or out-of-office), specifically aiming to level the fluctuations and peaks in BP readings.

All current BP measurement methods have imperfect reproducibility owing to the continuous fluctuation in BP readings, making it difficult to accurately diagnose hypertension.

Accumulating evidence from clinical trials, large registries and meta-analyses shows that increased BP variability predicts cardiovascular outcome, independently of the average BP values.

To date, BP variability is overlooked, with limited application in clinical practice, probably owing to a variety of complex non-standardized BP variability assessment methods and indices, and uncertain thresholds and clinical usefulness.

Novel cuffless wearable BP technologies can provide very large numbers of readings for days and months without the discomfort of traditional BP monitoring devices, and have the potential to replace current BP methods, once accuracy issues are resolved and their clinical usefulness is proved.

Changes in late-life systolic blood pressure and all-cause mortality among oldest-old people in China: the chinese longitudinal healthy longevity survey

Background

Blood pressure targets for oldest-old people have been long debated due to the concern that more stringent targets are associated with increased mortality. We aimed to investigate the association between changes of late-life systolic blood pressure (SBP), mean SBP and SBP variability (SBPV), and all-cause mortality in oldest-old.

Methods

Based on the community-based Chinese Longitudinal Healthy Longevity Survey with follow-up conducted in the 3-year interval, we assembled a retrospective cohort of 6639 participants ≥ 80 years with available blood pressure measurements at baseline and second wave. The primary exposures were mean SBP and SBPV (defined as the annual difference in SBP divided by mean SBP) measured between baseline and second wave. The primary outcome was all-cause mortality assessed from the second wave.

Results

During 21443.1 person-years of follow-up, 4622 death was recorded. U-shaped associations of mortality with mean SBP and SBPV were identified; the value of 137 mmHg and 4.0 %/year conferred the minimum mortality risk, respectively. The associations of a larger SBPV with an increased mortality risk were observed for both rises and large falls in SBP. The hazard ratio was 1.11 (comparing lowest versus middle quintile; 95 % CI: 1.01, 1.22) with large falls in SBPV and 1.08 (comparing highest versus middle quintile; 95 % CI: 0.98, 1.18) with large rises in SBPV.

Conclusions

U-shaped associations between late-life SBP and SBPV and all-cause mortality were found. Our study suggests that a stable SBP level in the middle range is related to lower mortality risk in the oldest-old.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02492-4.

Blood pressure visit-to-visit variability and outcomes in patients with heart failure with preserved ejection fraction

AIMS

Previous studies report that blood pressure (BP) variability is associated with increased risk of adverse outcomes in patients diagnosed with cardiovascular disease. However, studies have not fully explored this association in patients with heart failure with preserved ejection fraction (HFpEF). This study sought to explore the association between visit-to-visit variability (VVV) of BP and clinical outcomes in patients with HFpEF.

METHODS AND RESULTS

A total of 1988 patients (mean age of 67.73 ± 9.22, 51.7% female) from the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist (TOPCAT) trial were included in this study. BP-VVV was determined by standard deviation (SD) of mean systolic BP (SBP-SD) from six measurements (baseline and months 1, 2, 4, 8, and 12) during the first 12 months after randomization. Mean on-treatment SBP during the first 12 months was 127.77 ± 10.42 mmHg, and the median of SBP-SD was 8.15 mmHg. A total of 192 (9.7%) patients met the primary outcome during the subsequent median follow-up of 35.16 months, including a composite of cardiovascular death, heart failure hospitalization, or aborted cardiac arrest. Multiple Cox regression analysis showed that SBP-SD was independently associated with the increased risk of the primary outcome after adjusting for age, gender, method of BP measurement, treatment, renal function and common co-morbidities, and the mean SBP during the first 12 months [hazard ratio (HR) for fourth vs. first quartile, 1.63; 95% confidence interval (CI), 1.07-2.49; P = 0.024]. Analysis showed that SBP-SD as continuous variable was associated with a 23% increase in the risk of primary outcome (HR 1.23, 95% CI 1.06-1.43; P = 0.006).

CONCLUSIONS

The findings of the current study show that high SBP-VVV in patients with HFpEF is associated with an increased risk of adverse outcomes independent of the mean on-treatment SBP.

Associations of falls and severe falls with blood pressure and frailty among Chinese community-dwelling oldest olds: The Chinese Longitudinal Health and Longevity Study

INTRODUCTION

Falls are a leading cause of death among Chinese oldest olds. However, studies on Chinese community-dwelling older adults are lacking. We aimed to identify the associations of falls and severe falls with blood pressure and frailty among Chinese community-dwelling oldest olds.

METHODS

Cross-sectional analyses were conducted with 6,595 community-dwelling oldest olds (aged ≥80 years) from 22 Chinese provinces from the Chinese Longitudinal Health and Longevity Study (CLHLS). Systolic BP (SBP) and diastolic BP (DBP) were measured twice at participants' homes, and a 38-item frailty index was used to assess the frailty status of participants. Falls and severe falls were confirmed through face-to-face interviews. Multivariate logistic regression was used to investigate the associations of BP and frailty with falls and severe falls.

RESULTS

The mean participant age was 91.0 years, and 56.1% were female. In total, 24.2% participants had a history of fall and 8.3% had a history of severe falls. The multivariate-adjusted odds ratio (OR) for falls among the oldest old with SBP ≥140 mm Hg compared to those with an SBP of 120-129 mm Hg was 1.20 (95% confidence interval [CI], 1.01-1.44). The adjusted OR for falls among frail participants compared to robust participants was 1.39 (95% CI, 1.02-1.89). DBP and pre-frailty were not associated with falls after multivariate adjustment. SBP, DBP, and frailty status were not associated with severe falls after multivariate adjustment.

CONCLUSIONS

SBP and frailty but not DBP and pre-frailty are associated with increased odds of falls among Chinese community-dwelling oldest olds.

Impact of home telemonitoring and management support on blood pressure control in non-dialysis CKD: a systematic review protocol

INTRODUCTION

Hypertension is a common public health problem and a key modifiable risk factor for cardiovascular (CV) and chronic kidney disease (CKD). Home blood pressure (BP) telemonitoring (HBPT) and management is associated with improved BP control, accelerated delivery of care and decision-making strategies that can reduce adverse outcomes associated with hypertension. The aim of this paper is to describe the protocol for a systematic review to assess the impact of HBPT interventions used for improving BP control and reducing CV and kidney outcomes in non-dialysis CKD patients.

METHODS

We developed this protocol using the Preferred Reporting Items for Systematic reviews and Meta-Analyses for Protocols 2015. We will search empirical databases such as MEDLINE, Embase, Cochrane Library, CINAHL, Web of Science and PsycINFO and grey literature for studies conducted in non-dialysis CKD patients on interventions using HBPT and reporting outcomes related to BP control and other outcomes such as CV events and kidney disease progression. All studies meeting these criteria, in adults and published from inception until 2020 with no language barrier will be included.

ETHICS AND DISSEMINATION

Ethical approval will not be required for this review as the data used will be extracted from already published studies with publicly accessible data. As this study will assess the impact of HBPT on BP control in non-dialysis CKD patients, evidence gathered through it will be disseminated using traditional approaches that includes open-access peer-reviewed publication, scientific presentations and a report. We will also disseminate our findings to appropriate government agencies.

PROSPERO REGISTRATION NUMBER

CRD42020190705).

Effectiveness of statin intensive therapy in type 2 diabetes mellitus with high visit-to-visit blood pressure variability

BACKGROUND

Intensive lipid-lowering therapy is recommended in type 2 diabetes mellitus (T2DM) patients with target organ damage. However, the evidence is insufficient to stratify the patients who will benefit from the intensive therapy among them. High visit-to-visit variability in systolic blood pressure (SBP) is associated with increased risk of cardiovascular events. We investigated the effectiveness of intensive versus standard statin therapy in the primary prevention of cardiovascular events among T2DM patients with retinopathy stratified by visit-to-visit SBP variability.

METHODS

The standard versus intensive statin therapy for hypercholesterolemic patients with diabetic retinopathy study was the first trial comparing statin intensive therapy targeting low-density lipoprotein cholesterol (LDL-C) <70 mg/dl and standard therapy targeting LDL-C ≥100 to <120 mg/dl in T2DM patients with retinopathy without known cardiovascular disease. Using this dataset, we divided the patients into two subpopulations based on standard deviation (SD) and average real variability (ARV) of clinic SBP within the initial 6 months.

RESULTS

In a total of 4899 patients, 240 composite cardiovascular events were observed during a median follow-up of 37.3 months. In multivariable-adjusted model comparing intensive versus standard therapy, the hazard ratios for composite cardiovascular events were 0.64 (95% CI 0.45-0.90) and 1.21 (95% CI 0.82-1.80) in patients with high and low SBP variability as defined by SD, respectively. Interaction between SBP variability and statin therapy was significant (P = 0.018). The analysis using ARV of SBP showed similar results.

CONCLUSION

Statin intensive therapy targeting LDL-C <70 mg/dl had benefits in primary prevention of cardiovascular events compared with standard therapy among T2DM patients with retinopathy having high, but not low, visit-to-visit SBP variability.

Prediction models and nomograms for 10-year risk of end-stage renal disease in Chinese type 2 diabetes mellitus patients in primary care

AIMS

To develop and validate 10-year risk prediction models, nomograms and charts for end-stage renal disease (ESRD) in Chinese patients with type 2 diabetes mellitus (T2DM) in primary care, in order to guide individualized treatment.

MATERIALS AND METHODS

This was a 10-year population-based observational cohort study. A total of 141 516 Chinese T2DM patients without history of cardiovascular disease or ESRD who were managed in public primary care clinics in 2008 were included and followed up until December 2017. Two-thirds of these patients were randomly selected to develop sex-specific ESRD risk prediction models using Cox regressions. The validity and accuracy of the models were tested on the remaining third of patients using Harrell's C-index. We selected variables based on their clinical and statistical importance to construct the nomograms and charts.

RESULTS

The median follow-up period was 9.75 years. The cumulative incidence of ESRD was 6.0% (men: 6.1%, women: 5.9%). Age, diabetes duration, systolic blood pressure (SBP), SBP variability, diastolic blood pressure, triglycerides, glycated haemoglobin (HbA1c), HbA1c variability, urine albumin to creatinine ratio (UACR), and estimated glomerular filtration rate (eGFR) were significant predictors for both sexes. Smoking and total cholesterol to HDL cholesterol ratio were additional significant predictors for men and women, respectively. The models showed Harrell's C-statistics of 0.889/0.889 (women/men). Age, eGFR, UACR, SBP and HbA1c were selected for both sexes to develop nomograms and charts.

CONCLUSIONS

Using routinely available variables, the 10-year ESRD risk of Chinese T2DM patients in primary care can be predicted with approximately 90% accuracy. We have developed different tools to facilitate routine ESRD risk prediction in primary care, so that individualized care can be provided to prevent or delay ESRD in T2DM patients.