Prognostic importance of clinic and home blood pressure recordings in patients with chronic kidney disease

Masked phenomenon: renal and cardiovascular complications; review and updates

BACKGROUND

In the in-clinic blood pressure (BP) recording setting, a sizable number of individuals with normal BP and approximately 30% of patients with chronic renal disease (CKD) exhibit elevated outpatient BP records. These individuals are known as masked hypertension (MHTN), and when they are on antihypertensive medications, but their BP is not controlled, they are called masked uncontrolled hypertension (MUHTN). The masked phenomenon (MP) (MHTN and MUHTN) increases susceptibility to end-organ damage (a two-fold greater risk for cardiovascular events and kidney dysfunction). The potential extension of the observed benefits of MP therapy, including a reduction in end-organ damage, remains questionable.

AIM AND METHODS

This review aims to study the diagnostic methodology, epidemiology, pathophysiology, and significance of MP management in end-organs, especially the kidneys, cardiovascular system, and outcomes. To achieve the purposes of this non-systematic comprehensive review, PubMed, Google, and Google Scholar were searched using keywords, texts, and phrases such as masked phenomenon, CKD and HTN, HTN types, HTN definition, CKD progression, masked HTN, MHTN, masked uncontrolled HTN, CKD onset, and cardiovascular system and MHTN. We restricted the search process to the last ten years to search for the latest updates.

CONCLUSION

MHTN is a variant of HTN that can be missed if medical professionals are unaware of it. Early detection by ambulatory or home BP recording in susceptible individuals reduces end-organ damage and progresses to sustained HTN. Adherence to the available recommendations when dealing with masked phenomena is justifiable; however, further studies and recommendation updates are required.

Novel biomarkers in patients with uncontrolled hypertension with and without kidney damage

INTRODUCTION

Estimated glomerular filtration rate (eGFR) and urine albumin/creatinine ratio (ACR) are insensitive biomarkers for early detection of hypertension-mediated organ damage (HMOD). In this nationwide cross-sectional study, we assessed potential biomarkers for early HMOD in healthy persons and patients with hypertension. We hypothesised that plasma levels of biomarkers: (1) are different between healthy controls and patients with hypertension, (2): can classify patients with hypertension according to the degree of hypertension severity.

DESIGN AND METHODS

Patients with hypertension prescribed ≥2 antihypertensive agents were selected from a multicentre study. Healthy controls were selected from an ongoing study of living kidney donor candidates. Uncontrolled hypertension was defined as systolic daytime ambulatory blood pressure ≥135 mmHg. Kidney HMOD was defined by ACR > 3.0 mg/mmol or eGFR < 60 mL/min/1.73 m2. Patients with hypertension were categorised into three groups: (1) controlled hypertension; (2) uncontrolled hypertension without kidney HMOD; (3) uncontrolled hypertension with kidney HMOD. Fifteen biomarkers were analysed using a Luminex bead-based immunoassay, and nine fell within the specified analytical range.

RESULTS

Plasma levels of Interleukin 1 receptor antagonist (IL-1RA), neutrophil gelatinase-associated lipocalin (NGAL) and uromodulin were significantly different between healthy controls (n = 39) and patients with hypertension (n = 176). In regression models, with controlled hypertension (n = 55) as the reference category, none of the biomarkers were associated with uncontrolled hypertension without (n = 59) and with (n = 62) kidney HMOD. In models adjusted for cardiovascular risk factors and eGFR, osteopontin (OPN) was associated with uncontrolled hypertension without kidney HMOD (odds ratio (OR) 1.77 (1.05-2.98), p = 0.03), and regulated upon activation normal T-cell expressed and secreted (RANTES) with uncontrolled hypertension with kidney HMOD (OR 0.57 (0.34-0.95), p = 0.03).

CONCLUSIONS

None of the biomarkers could differentiate our hypertension groups when established risk factors were considered. Plasma OPN may identify patients with uncontrolled hypertension at risk for kidney HMOD.

Comparison of whole body versus thoracic bioimpedance in relation to ultrafiltration volume and systolic blood pressure during hemodialysis

In contrast to whole body bioimpedance, which estimates fluid status at a single point in time, thoracic bioimpedance applied by a wearable device could enable continuous measurements. However, clinical experience with thoracic bioimpedance in patients on dialysis is limited. To test the reproducibility of whole body and thoracic bioimpedance measurements and to compare their relationship with hemodynamic changes during hemodialysis, these parameters were measured pre- and end-dialysis in 54 patients during two sessions. The resistance from both bioimpedance techniques was moderately reproducible between two dialysis sessions (intraclass correlations of pre- to end-dialysis whole body and thoracic resistance between session 1 and 2 were 0.711 [0.58-0.8] and 0.723 [0.6-0.81], respectively). There was a very high to high correlation between changes in ultrafiltration volume and changes in whole body thoracic resistance. Changes in systolic blood pressure negatively correlated to both bioimpedance techniques. Although the relationship between changes in ultrafiltration volume and changes in resistance was stronger for whole body bioimpedance, the relationship with changes in blood pressure was at least comparable for thoracic measurements. These results suggest that thoracic bioimpedance, measured by a wearable device, may serve as an interesting alternative to whole body measurements for continuous hemodynamic monitoring during hemodialysis.NEW & NOTEWORTHY We examined the role of whole body and thoracic bioimpedance in hemodynamic changes during hemodialysis. Whole body and thoracic bioimpedance signals were strongly related to ultrafiltration volume and moderately, negatively, to changes in blood pressure. This work supports the further development of a wearable device measuring thoracic bioimpedance longitudinally in patients on hemodialysis. As such, it may serve as an innovative tool for continuous hemodynamic monitoring during hemodialysis in hospital or in a home-based setting.

Hypertension in chronic kidney disease-treatment standard 2023

Hypertension is very common and remains often poorly controlled in patients with chronic kidney disease (CKD). Accurate blood pressure (BP) measurement is the essential first step in the diagnosis and management of hypertension. Dietary sodium restriction is often overlooked, but can improve BP control, especially among patients treated with an agent to block the renin-angiotensin system. In the presence of very high albuminuria, international guidelines consistently and strongly recommend the use of an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker as the antihypertensive agent of first choice. Long-acting dihydropyridine calcium channel blockers and diuretics are reasonable second- and third-line therapeutic options. For patients with treatment-resistant hypertension, guidelines recommend the addition of spironolactone to the baseline antihypertensive regimen. However, the associated risk of hyperkalemia restricts the broad utilization of spironolactone in patients with moderate-to-advanced CKD. Evidence from the CLICK (Chlorthalidone in Chronic Kidney Disease) trial indicates that the thiazide-like diuretic chlorthalidone is effective and serves as an alternative therapeutic opportunity for patients with stage 4 CKD and uncontrolled hypertension, including those with treatment-resistant hypertension. Chlorthalidone can also mitigate the risk of hyperkalemia to enable the concomitant use of spironolactone, but this combination requires careful monitoring of BP and kidney function for the prevention of adverse events. Emerging agents, such as the non-steroidal mineralocorticoid receptor antagonist ocedurenone, dual endothelin receptor antagonist aprocitentan and the aldosterone synthase inhibitor baxdrostat offer novel targets and strategies to control BP better. Larger and longer term clinical trials are needed to demonstrate the safety and efficacy of these novel therapies in the future. In this article, we review the current standards of treatment and discuss novel developments in pathophysiology, diagnosis, outcome prediction and management of hypertension in patients with CKD.

Measurement of Blood Pressure in Chronic Kidney Disease: Time to Change Our Clinical Practice - A Comprehensive Review

Chronic kidney disease (CKD) is extremely common all over the world and is strongly linked to cardiovascular disease (CVD). The great majority of CKD patients have hypertension, which raises the risk of cardiovascular disease (CVD), end-stage kidney disease, and mortality. Controlling hypertension in patients with CKD is critical in our clinical practice since it slows the course of the disease and lowers the risk of CVD. As a result, accurate blood pressure (BP) monitoring is crucial for CKD diagnosis and therapy. Three important guidelines on BP thresholds and targets for antihypertensive medication therapy have been published in the recent decade emphasizing the way we measure BP. For both office BP and out-of-office BP measuring techniques, their clinical importance in the management of hypertension has been well defined. Although BP measurement is widely disseminated and routinely performed in most clinical settings, it remains unstandardized, and practitioners frequently fail to follow the basic recommendations to avoid measurement errors. This may lead to misdiagnosis and wrong management of hypertension, especially in CKD patients. Here, we review presently available all BP measuring techniques and their use in clinical practice and the recommendations from various guidelines and research gaps emphasizing CKD patients.

Assessment of hypertension in kidney transplantation by ambulatory blood pressure monitoring: a systematic review and meta-analysis

Background

Hypertension (HTN) is common following renal transplantation and it is associated with adverse effects on cardiovascular (CV) and graft health. Ambulatory blood pressure monitoring (ABPM) is the preferred method to characterize blood pressure (BP) status, since HTN misclassification by office BP (OBP) is quite common in this population. We performed a systematic review and meta-analysis aimed at determining the clinical utility of 24-h ABPM and its potential implications for the management of HTN in this population.

Methods

Ovid-MEDLINE and PubMed databases were searched for interventional or observational studies enrolling adult kidney transplant recipients (KTRs) undergoing 24-h ABP readings compared with OBP or home BP. The main outcome was the proportion of KTRs diagnosed with HTN by ABPM, home or OBP recordings. Additionally, day-night BP variability and dipper/non-dipper status were assessed.

Results

Forty-two eligible studies (4115 participants) were reviewed. A cumulative analysis including 27 studies (3481 participants) revealed a prevalence of uncontrolled HTN detected by ABPM of 56% [95% confidence interval (CI) 46-65%]. The pooled prevalence of uncontrolled HTN according to OBP was 47% (95% CI 36-58%) in 25 studies (3261 participants). Very few studies reported on home BP recordings. The average concordance rate between OBP and ABPM measurements in classifying patients as controlled or uncontrolled hypertensive was 66% (95% CI 59-73%). ABPM revealed HTN phenotypes among KTRs. Two pooled analyses of 11 and 10 studies, respectively, revealed an average prevalence of 26% (95% CI 19-33%) for masked HTN (MHT) and 10% (95% CI 6-17%) for white-coat HTN (WCH). The proportion of non-dippers was variable across the 28 studies that analysed dipping status, with an average prevalence of 54% (95% CI 45-63%).

Conclusions

In our systematic review, comparison of OBP versus ABP measurements disclosed a high proportion of MHT, uncontrolled HTN and, to a lesser extent, WCH in KTRs. These results suggest that HTN is not adequately diagnosed and controlled by OBP recordings in this population. Furthermore, the high prevalence of non-dippers confirmed that circadian rhythm is commonly disturbed in KTRs.

Management of hypertension and renin-angiotensin-aldosterone system blockade in adults with diabetic kidney disease: Association of British Clinical Diabetologists and the Renal Association UK guideline update 2021

People with type 1 and type 2 diabetes are at risk of developing progressive chronic kidney disease (CKD) and end-stage kidney failure. Hypertension is a major, reversible risk factor in people with diabetes for development of albuminuria, impaired kidney function, end-stage kidney disease and cardiovascular disease. Blood pressure control has been shown to be beneficial in people with diabetes in slowing progression of kidney disease and reducing cardiovascular events. However, randomised controlled trial evidence differs in type 1 and type 2 diabetes and different stages of CKD in terms of target blood pressure. Activation of the renin-angiotensin-aldosterone system (RAAS) is an important mechanism for the development and progression of CKD and cardiovascular disease. Randomised trials demonstrate that RAAS blockade is effective in preventing/ slowing progression of CKD and reducing cardiovascular events in people with type 1 and type 2 diabetes, albeit differently according to the stage of CKD. Emerging therapy with sodium glucose cotransporter-2 (SGLT-2) inhibitors, non-steroidal selective mineralocorticoid antagonists and endothelin-A receptor antagonists have been shown in randomised trials to lower blood pressure and further reduce the risk of progression of CKD and cardiovascular disease in people with type 2 diabetes. This guideline reviews the current evidence and makes recommendations about blood pressure control and the use of RAAS-blocking agents in different stages of CKD in people with both type 1 and type 2 diabetes.

New Aspects in the Management of Hypertension in Patients with Chronic Kidney Disease not on Renal Replacement Therapy

With chronic kidney disease (CKD) being a global arising health problem, strategies for delaying kidney disease progression and reducing the high cardiovascular risk inherent to CKD, are the main objectives of the actual management of patients with kidney diseases. In these patients, the control of arterial hypertension is essential, as high blood pressure (BP) is a strong determinant of worst cardiovascular and renal outcomes. Achieving target blood pressures recommended by international guidelines is mandatory and often demands a multiple levels management, including several pharmacological and lifestyle measures. Even in the presence of adequate BP control, the residual cardiovascular risk remains high. In this respect, the recent demonstration that novel agents such as sodium glucose transporter 2 (SGLT2) inhibitors or the new non-steroidal mineralocorticoid antagonist finerenone can retard the progression of kidney diseases and reduce cardiovascular mortality on top of standard of care treatment with renin-angiotensin system inhibitors represent enormous progresses. These studies also demonstrate that cardiovascular and renal protection can be obtained beyond blood pressure control. Other promising novelties are still to come such as renal denervation and endothelin receptor antagonists in the setting of diabetic and non-diabetic kidney diseases. In the present review, we shall discuss the classic and the new aspects for the management of hypertension in CKD, integrating the new data from recent clinical studies.

Home blood pressure monitoring: methodology, clinical relevance and practical application: a 2021 position paper by the Working Group on Blood Pressure Monitoring and Cardiovascular Variability of the European Society of Hypertension

The present paper provides an update of previous recommendations on Home Blood Pressure Monitoring from the European Society of Hypertension (ESH) Working Group on Blood Pressure Monitoring and Cardiovascular Variability sequentially published in years 2000, 2008 and 2010. This update has taken into account new evidence in this field, including a recent statement by the American Heart association, as well as technological developments, which have occurred over the past 20 years. The present document has been developed by the same ESH Working Group with inputs from an international team of experts, and has been endorsed by the ESH.

Hypertension in Chronic Kidney Disease (CKD): Diagnosis, Classification, and Therapeutic Targets

Blood pressure (BP) in the office is often recorded without standardization of the technique of measurement. When office BP measurement is performed with a research-grade methodology, it can inform better therapeutic decisions. The reference-standard method of ambulatory BP monitoring (ABPM) together with the assessment of BP in the office enables the identification of white-coat and masked hypertension, facilitating the stratification of cardiorenal risk. Compared with general population, the prevalence of resistant hypertension is 2- to 3-fold higher among patients with chronic kidney disease (CKD). The use of ABPM is mandatory in order to exclude the white-coat effect, a common cause of pseudoresistance, and confirm the diagnosis of true-resistant hypertension. After the premature termination of Systolic Blood Pressure Intervention Trial due to an impressive cardioprotective benefit of intensive BP-lowering, the 2017 American Heart Association/American College of Cardiology guideline reappraised the definition of hypertension and recommended a tighter BP target of <130/80 mm Hg for the majority of adults with a high cardiovascular risk profile, inclusive of patients with CKD. However, the benefit/risk ratio of intensive BP-lowering in particular subsets of patients with CKD (i.e., those with diabetes or more advanced CKD) continues to be debated. We explore the controversial issue of BP targets in CKD, providing a critical evaluation of the available clinical-trial evidence and guideline recommendations. We argue that the systolic BP target in CKD, if BP is measured correctly, should be <120 mm Hg.

Hypertension Canada's 2020 Comprehensive Guidelines for the Prevention, Diagnosis, Risk Assessment, and Treatment of Hypertension in Adults and Children

Hypertension Canada's 2020 guidelines for the prevention, diagnosis, risk assessment, and treatment of hypertension in adults and children provide comprehensive, evidence-based guidance for health care professionals and patients. Hypertension Canada develops the guidelines using rigourous methodology, carefully mitigating the risk of bias in our process. All draft recommendations undergo critical review by expert methodologists without conflict to ensure quality. Our guideline panel is diverse, including multiple health professional groups (nurses, pharmacy, academics, and physicians), and worked in concert with experts in primary care and implementation to ensure optimal usability. The 2020 guidelines include new guidance on the management of resistant hypertension and the management of hypertension in women planning pregnancy.

Secondary Hypertension in Children and Adolescents: Novel Insights

Hypertension is a significant risk factor for cardiovascular morbidity and mortality, not only in adults, but in youths also, as it is associated with long-term negative health effects. The predominant type of hypertension in children is the secondary hypertension, with the chronic kidney disease being the most common cause, however, nowadays, there is a rising incidence of primary hypertension due to the rising incidence of obesity in children. Although office blood pressure has guided patient management for many years, ambulatory blood pressure monitoring provides useful information, facilitates the diagnosis and management of hypertension in children and adolescents, by monitoring treatment and evaluation for secondary causes or specific phenotypes of hypertension. In the field of secondary hypertension, there are numerous studies, which have reported a strong association between different determinants of 24-hour blood pressure profile and the underlying cause. In addition, in children with secondary hypertension, ambulatory blood pressure monitoring parameters offer the unique advantage to identify pediatric low- and high-risk children for target organ damage. Novel insights in the pathogenesis of hypertension, including the role of perinatal factors or new cardiovascular biomarkers, such as fibroblast growth factor 23, need to be further evaluated in the near future.

Factors Associated With Physician Recommendation of Home Blood Pressure Monitoring and Blood Pressure in the US Population

BACKGROUND

Hypertension guidelines recommend home blood pressure monitoring (HBPM) to help achieve blood pressure (BP) control. We hypothesized that HBPM use with a physician recommendation would be associated with lower BP and greater medication adherence.

METHODS

We used data from 6,320 adults with hypertension in the National Health and Nutrition Examination Survey 2009-2014 to characterize the association of (i) provider recommendation for HBPM and (ii) HBPM use on 2 outcomes: measured BP (linear regression) and medication adherence (logistic regression). Provider recommendation, HBPM use, and medication use were self-reported.

RESULTS

Among adults with hypertension, 30.1% reported a physician recommendation for HBPM, among whom 82.0% reported using HBPM. Among those who did not report a physician recommendation for HBPM, 28.3% used HBPM. Factors associated with a physician recommendation were having health insurance, higher education attainment, hypertension awareness, and having a prescription for antihypertensive medication. Among those who reported receiving a physician recommendation, those who used HBPM had a mean BP that was 3.1/4.5 mm Hg lower than those who did not. Those who reported having a physician recommendation and using HBPM were more likely to report hypertension medication adherence (odds ratio 2.9; 95% confidence interval: 2.0, 4.4).

CONCLUSIONS

HBPM use was associated with lower BP and higher medication adherence. Use of HBPM was higher among those with a physician recommendation. These results support a role for physicians in counseling and partnering with patients on HBPM use for BP management.

Blood Pressure Measurement: A KDOQI Perspective

The majority of patients with chronic kidney disease (CKD) have elevated blood pressure (BP). In patients with CKD, hypertension is associated with increased risk for cardiovascular disease, progression of CKD, and all-cause mortality. New guidelines from the American College of Cardiology/American Heart Association (ACC/AHA) recommend new thresholds and targets for the diagnosis and treatment of hypertension in patients with and without CKD. A new aspect of the guidelines is the recommendation for measurement of out-of-office BP to confirm the diagnosis of hypertension and guide therapy. In this KDOQI (Kidney Disease Outcomes Quality Initiative) perspective, we review the recommendations for accurate BP measurement in the office, at home, and with ambulatory BP monitoring. Regardless of location, validated devices and appropriate cuff sizes should be used. In the clinic and at home, proper patient preparation and positioning are critical. Patients should receive information about the importance of BP measurement techniques and be encouraged to advocate for adherence to guideline recommendations. Implementing appropriate BP measurement in routine practice is feasible and should be incorporated in system-wide efforts to improve the care of patients with hypertension. Hypertension is the number 1 chronic disease risk factor in the world; BP measurements in the office, at home, and with ambulatory BP monitoring should adhere to recommendations from the AHA.

Blood pressure phenotype reproducibility in CKD outpatients: a clinical practice report

Out-of-office blood pressure (BP) measurement is encouraged by recent hypertension guidelines for assessing BP phenotypes. These showed acceptable reproducibility in the short term, but few data exist about long-term reproducibility, particularly for chronic kidney disease (CKD) patients. We evaluated changes of the BP phenotypes at 6 and 12 months in 280 consecutive non-dialysis CKD outpatients (186 males, age 71 ± 12 years, eGFR 38 ± 13 ml/min/1.73), without any change in drug therapy. Elevated BP is defined as office BP > 140/90 and home BP > 135/85 mmHg for defining the following BP phenotypes: sustained uncontrolled hypertension (SUCH); white-coat uncontrolled hypertension (WUCH); masked uncontrolled hypertension (MUCH); and controlled hypertension (CH). At baseline, the prevalence of the phenotypes was SUCH 36.6%, CH 30.1%, WUCH 25.4% and MUCH 7.9%, and it was similar at 6 months and 12 months. On the other hand, individual phenotype reproducibility at 12 months was poor both overall (38.0%) and across the different phenotypes (SUCH 53.9%, WUCH 32.4% and CH 32.1%, MUCH 9.1%). Patients who were not maintaining the same phenotype (non-concordant) were not distinguished by age, sex, BMI, eGFR, presence of diabetes or cardiovascular disease, or pharmacological therapy. When reproducibility of BP phenotypes both at 6 months and at 12 months was assessed, it was very low (19.6%), particularly for MUCH (0%), CH (14%) and WUCH (15.5%), while it was 31% for SUCH. In a CKD cohort, the overall prevalence of the different BP phenotypes defined by office and home BP remains constant over time. However, only 38% of patients maintained the same phenotype at 12 months, suggesting a poor reproducibility over time for the BP phenotypes.

Ambulatory blood pressure monitoring-based analysis of long-term outcomes for kidney disease progression

Non-dipping nocturnal blood pressure (BP) pattern is a predictor of the future decline of renal function; however, it is unclear whether it is still a risk for chronic kidney disease (CKD) patients with normal BP. To solve this question, a retrospective cohort study was conducted, and 1107 CKD patients who underwent ambulatory blood pressure monitoring (ABPM) were enrolled. We divided patients into 4 groups based on their nocturnal BP dipping pattern (dipper or non-dipper) and average 24-hour BP (hypertension or normotension). The cumulative incidence of composite renal outcomes, including a 40% reduction in eGFR, the induction of renal-replacement therapy, or death from renal causes, was analyzed. Overall, 86.1% of participants were non-dippers and 48.2% of them were normotensive. During the median follow-up period of 4.72 years, the incidence of renal composite outcomes was highest in hypertensive non-dipper patients, and was similar between normotensive dipper and non-dipper patients. Multivariate regression analysis revealed that the 24-hour systolic BP, amount of urinary protein, and hemoglobin values were associated with the incidence of renal outcomes. In conclusion, our ABPM-based analysis revealed that a non-dipping BP pattern with normotension does not predict the future incidence of composite renal outcomes in CKD patients.

High frequency of nocturnal hypertension in lupus nephritis: should ABPM be implemented in usual practice?

INTRODUCTION/OBJECTIVES

Hypertension management in lupus nephritis (LN) is guided by in-office blood pressure (BP); however, recent studies demonstrate that lupus patients frequently have nocturnal hypertension and reduced BP dipping. The aim of the study was to evaluate 24-h blood pressure in patients with active LN and after response to treatment.

METHODS

Seventy active LN patients were evaluated during a LN flare by ambulatory blood pressure monitoring (ABPM). Later, 10 patients with complete response were re-evaluated after 12 months along with 20 matched controls. Overall, daytime and nightime BP, day-to-night dipping, BP load and variability, and the incidence of abnormal BP patterns were assessed. Blood pressure levels were correlated with clinical and histologic parameters and independent associations evaluated by linear regression.

RESULTS

Overall systolic hypertension occurred in 25 (36%) patients and diastolic hypertension in 28 (40%). Nighttime systolic and diastolic hypertension occurred in 35 (50%) and 44 (63%) of patients, respectively. Nocturnal systolic day-to-night BP decrease was abnormal in 59 (84%) patients. Only 18 (26%) were diagnosed with HT by in-office evaluation while 29 (41%) had masked hypertension (MH)/masked uncontrolled hypertension (MUCH), and 3 (4%) had white coat hypertension. Patients with MH had lower eGFR, complement C3, hemoglobin, and higher systolic variability compared with patients with normal BP. Systolic and diastolic BP levels were associated with the years under corticosteroid treatment, activity biomarkers (proteinuria, complement C3), and the degree of interstitial inflammation in the kidney biopsy. A re-evaluation at 12 months showed that although 9 out of 10 patients had normal in-office BP and BP loads improved, still 5 patients remained with MH due to nocturnal hypertension, and 7 remained with abnormal day-to-night dipping. These numbers were higher than those of matched controls.

CONCLUSIONS

Due to the high frequency of nocturnal hypertension and abnormal day-to-night dipping, office BP measurements alone may not be sufficient to guide hypertension management in patients with LN.Key Points• Nocturnal hypertension and abnormal BP patterns are frequent and not detectable by the standard in-office BP evaluation in LN patients.• BP abnormalities may not be fully corrected after a complete clinical response to treatment in lupus nephritis and are only detectable by ABPM.• The degree of interstitial inflammation in the kidney biopsy in LN patients is associated to BP levels. This supports the hypotheses underlining the role of interstitial inflammation in salt sensitivity and hypertension.

International consensus statement on the diagnosis and management of autosomal dominant polycystic kidney disease in children and young people

These recommendations were systematically developed on behalf of the Network for Early Onset Cystic Kidney Disease (NEOCYST) by an international group of experts in autosomal dominant polycystic kidney disease (ADPKD) from paediatric and adult nephrology, human genetics, paediatric radiology and ethics specialties together with patient representatives. They have been endorsed by the International Pediatric Nephrology Association (IPNA) and the European Society of Paediatric Nephrology (ESPN). For asymptomatic minors at risk of ADPKD, ongoing surveillance (repeated screening for treatable disease manifestations without diagnostic testing) or immediate diagnostic screening are equally valid clinical approaches. Ultrasonography is the current radiological method of choice for screening. Sonographic detection of one or more cysts in an at-risk child is highly suggestive of ADPKD, but a negative scan cannot rule out ADPKD in childhood. Genetic testing is recommended for infants with very-early-onset symptomatic disease and for children with a negative family history and progressive disease. Children with a positive family history and either confirmed or unknown disease status should be monitored for hypertension (preferably by ambulatory blood pressure monitoring) and albuminuria. Currently, vasopressin antagonists should not be offered routinely but off-label use can be considered in selected children. No consensus was reached on the use of statins, but mTOR inhibitors and somatostatin analogues are not recommended. Children with ADPKD should be strongly encouraged to achieve the low dietary salt intake that is recommended for all children.

Improved home BP profile with dapagliflozin is associated with amelioration of albuminuria in Japanese patients with diabetic nephropathy: the Yokohama add-on inhibitory efficacy of dapagliflozin on albuminuria in Japanese patients with type 2 diabetes study (Y-AIDA study)

Background

The Y-AIDA study was designed to investigate the renal- and home blood pressure (BP)-modulating effects of add-on dapagliflozin treatment in Japanese individuals with type 2 diabetes mellitus (T2DM) and albuminuria.

Methods

We conducted a prospective, multicenter, single-arm study. Eighty-six patients with T2DM, HbA1c 7.0–10.0%, estimated glomerular filtration rate (eGFR) ≥ 45 mL/min/1.73 m², and urine albumin-to-creatinine ratio (UACR) ≥ 30 mg/g creatinine (gCr) were enrolled, and 85 of these patients were administered add-on dapagliflozin for 24 weeks. The primary and key secondary endpoints were change from baseline in the natural logarithm of UACR over 24 weeks and change in home BP profile at week 24.

Results

Baseline median UACR was 181.5 mg/gCr (interquartile range 47.85, 638.0). Baseline morning, evening, and nocturnal home systolic/diastolic BP was 137.6/82.7 mmHg, 136.1/79.3 mmHg, and 125.4/74.1 mmHg, respectively. After 24 weeks, the logarithm of UACR decreased by 0.37 ± 0.73 (P < 0.001). In addition, changes in morning, evening, and nocturnal home BP from baseline were as follows: morning systolic/diastolic BP − 8.32 ± 11.42/− 4.18 ± 5.91 mmHg (both P < 0.001), evening systolic/diastolic BP − 9.57 ± 12.08/− 4.48 ± 6.45 mmHg (both P < 0.001), and nocturnal systolic/diastolic BP − 2.38 ± 7.82/− 1.17 ± 5.39 mmHg (P = 0.0079 for systolic BP, P = 0.0415 for diastolic BP). Furthermore, the reduction in UACR after 24 weeks significantly correlated with an improvement in home BP profile, but not with changes in other variables, including office BP. Multivariate linear regression analysis also revealed that the change in morning home systolic BP was a significant contributor to the change in log-UACR.

Conclusions

In Japanese patients with T2DM and diabetic nephropathy, dapagliflozin significantly improved albuminuria levels and the home BP profile. Improved morning home systolic BP was associated with albuminuria reduction.

Trial registration The study is registered at the UMIN Clinical Trials Registry (UMIN000018930; http://www.umin.ac.jp/ctr/index-j.htm). The study was conducted from July 1, 2015 to August 1, 2018.

Electronic supplementary material

The online version of this article (10.1186/s12933-019-0912-3) contains supplementary material, which is available to authorized users.

Masked Hypertension and Obesity in Renal Transplant Recipients

The diagnosis of arterial hypertension has traditionally been based on measurements of blood pressure (BP) in the clinic. However, home or ambulatory BP monitoring (ABPM) is reported to correlate better with target organ damage than clinic BP readings. The other potential advantage of out-of-clinic BP measurement is the detection of both white-coat hypertension (WCHT) and masked hypertension (MHT). Studies have suggested that MHT have an increased risk of cardiovascular disease (CVD). We aimed to investigate the prevalence of MHT and to evaluate risk factors by ABPM in our renal transplant recipients. One hundred twenty-ninety patients who were followed up in our nephrology clinic were included in the study. The prevalence of MHT was 17%. In logistic regression analysis, we investigated factors associated with MHT. In a model with age, sex, smoking, presence of Diabetes mellitus (DM) and blood glucose, estimated glomerular filtration rate (eGFR), donor type, body mass index, waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR), we found that WHR (r: 18.61, P: .007) and smoking (r: 2.79, P: .011) were related with MHT. MHT was related to target organ damage and cardiovascular disease. The diagnosis and treatment of MHT are important. These findings suggesting that patients with high WC and smokers should be investigated with ABPM to diagnose masked hypertension. This approach may reduce adverse cardiovascular outcomes after transplantation.

Masked Hypertension in CKD: Increased Prevalence and Risk for Cardiovascular and Renal Events

PURPOSE OF REVIEW

Hypertension and chronic kidney disease (CKD) are inextricably linked. The causal nature of the relationship is bidirectional. This relationship holds when blood pressure is assessed in the clinic and outside the clinic with home and ambulatory blood pressure monitoring. Patients with CKD are more likely to have high-risk hypertension phenotypes, such as masked and sustained hypertension, and are at increased risk for cardiovascular disease. The purpose of this review is to describe the increased prevalence of masked hypertension in patients with CKD and then describe the increased risk for target organ damage and adverse clinical events associated with masked hypertension in patients with CKD.

RECENT FINDINGS

The prevalence of masked hypertension is greater in patients with CKD than that of the general population. Recent studies have demonstrated that masked hypertension is associated with increased risk for target organ damage including left ventricular hypertrophy, elevated pulse wave velocity, proteinuria, and decreased estimated glomerular filtration rate in patients with CKD. Additionally, in patients with CKD, masked hypertension is associated with increased risk for cardiovascular disease, end-stage renal disease, and all-cause mortality. Patients with CKD are at increased risk for masked hypertension. Masked hypertension is associated with increased risk for target organ damage and adverse cardiovascular and renal outcomes in patients with CKD. Further research is necessary to better understand the pathophysiology of masked hypertension, the optimal method for diagnosing masked hypertension, and to determine whether masked hypertension is a modifiable risk factor.

KDOQI US Commentary on the 2017 ACC/AHA Hypertension Guideline

Hypertension is a modifiable risk factor for cardiovascular morbidity and mortality and reduction of elevated blood pressure (BP) remains an important intervention for slowing kidney disease progression. Over the past decade, the most appropriate BP target for initiation and titration of BP-lowering medications has been an area of intense research and debate within the clinical community. In 2017, the American College of Cardiology and the American Heart Association (ACC/AHA) in conjunction with several other professional societies released new hypertension guidelines based on data from a systematic review of clinical trials and observational data. While many of the recommendations in the ACC/AHA hypertension guideline are relevant to nephrology practice, BP targets and management strategies for patients receiving dialysis are not discussed. This Kidney Disease Outcomes Quality Initiative (KDOQI) commentary focuses largely on recommendations from the ACC/AHA hypertension guidelines that are pertinent to individuals at risk of chronic kidney disease or with non-dialysis-dependent chronic kidney disease. This KDOQI commentary also includes a brief discussion of the consensus statement regarding hypertension diagnosis and management for adults receiving maintenance dialysis published by the European Renal and Cardiovascular Medicine Working Group of the European Renal Association-European Dialysis and Transplant Association (ERA-EDTA) and the Hypertension and the Kidney working group of the European Society of Hypertension. Overall, we support the vast majority of the ACC/AHA recommendations and highlight select areas in which best diagnosis and treatment options remain controversial.

Assessment of Blood Pressure: Techniques and Implications From Clinical Trials

Hypertension is a global health problem and without adequate diagnosis and treatment is a risk factor for morbidity and mortality. Proper assessment of blood pressure is key to diagnosis and management of hypertension. Different methods of measurement are available for use and varying techniques are applied to patient care. Understanding the proper methods of blood pressure measurement both in and out of the physician's office is crucial for providing appropriate care to an individual patient. In addition, understanding the techniques used in research, on which current guidelines are based, is critical for proper application to daily practice. In this article, we review the types of blood pressure measurement techniques, discuss the benefits and limitations to each, explore future technological advances in measurement devices, and provide insight into research techniques, which ultimately guide our practice.

Masked hypertension and kidney function decline: the Jackson Heart Study

BACKGROUND

Hypertension diagnosed by blood pressure (BP) measured in the clinic is associated with rapid kidney function decline (RKFD) and incident chronic kidney disease (CKD). The extent to which hypertension defined using out-of-clinic BP measurements is associated with these outcomes is unclear.

METHODS

We evaluated the association of any masked hypertension (daytime SBP/DBP ≥ 135/85 mmHg, night-time SBP/DBP ≥ 120/70 mmHg or 24-h SBP/DBP ≥ 130/80 mmHg) with RKFD and incident CKD among 676 African-Americans in the Jackson Heart Study with clinic-measured SBP/DBP less than 140/90 mmHg who completed ambulatory BP monitoring in 2000-2004. RKFD was defined as a decline in estimated glomerular filtration rate (eGFR) at least 30% and incident CKD was defined as development of eGFR less than 60 ml/min per 1.73 m with an at least 25% decline in eGFR between 2000-2004 and 2009-2013.

RESULTS

The mean age of participants was 57.6 years, 28.8% were men and 52.7% had any masked hypertension. After a median follow-up of 8 years, 13.8 and 8.6% of participants had RKFD and incident CKD, respectively. In unadjusted analyses, masked hypertension was associated with an increased odds for incident CKD [odds ratio (OR) 2.20, 95% confidence interval (CI) 1.22, 3.97]. This association remained statistically significant after adjustment for demographic characteristics, baseline eGFR and albumin-to-creatinine ratio (OR 1.95, 95% CI 1.04, 3.67) but was eliminated after propensity score adjustment (OR 1.62, 95% CI 0.87, 3.00). There was no association between masked hypertension and RKFD.

CONCLUSION

Masked hypertension may be associated with the development of CKD in African-Americans.

Role and prognostic value of individual ambulatory blood pressure components in chronic kidney disease

Hypertension is a key risk factor for chronic kidney disease (CKD), but can also be a detrimental consequence of established CKD. Unsurprisingly, the majority of subjects with abnormal creatinine in the general population are also hypertensive, with a huge toll on national health care systems worldwide due to a staggering increase in the risk of cardiovascular complications and end-stage renal disease requiring renal replacement therapy. In this setting, a comprehensive and careful assessment of the whole 24-h blood pressure (BP) profile could be of paramount importance in ensuring a timely diagnosis of hypertension and an optimal therapeutic control. Hence, ambulatory BP monitoring (ABPM) has the potential to become the preferred method for optimal clinical management of CKD patients. ABPM might better define the relationship between BP, target organ damage (TOD), and clinical outcomes. Current evidence suggests that specific day-night BP components, along with average BP values, may have clinical relevance in such patients, despite the suboptimal statistical power of available studies and inconsistencies on the prognostic value of individual BP components. The main aim of our review is to scrutinize the evidence for the usage of ABPM in CKD patients, including the relationship between ambulatory BP recordings and cardiovascular events, and the distinctive features of ABPM in these subjects.

Comparison of Optimal Diagnostic Thresholds of Hypertension With Home Blood Pressure Monitoring and 24-Hour Ambulatory Blood Pressure Monitoring

BACKGROUND

Differences between the recently suggested outcome-driven diagnostic threshold of home blood pressure (HBP) measurements and the currently recommended diagnostic threshold of HBP measurements may cause a disagreement between 24-hour ambulatory blood pressure (ABP) and HBP measurements in the diagnosis of hypertension. We evaluated the agreement of various HBP diagnostic thresholds (135/85, 130/85, and 130/80 mm Hg) to ABP measurements, as a reference method.

METHODS

Patients who were confirmed to have high BP (≥140/90 mm Hg) at the outpatient clinic were referred. HBP measurement was performed for 7 days in triplicates every morning and evening. The 24-hour ABP measurement was performed on the 8th day. Using 24-hour ABP measurement as a reference method, we analyzed HBP diagnostic thresholds at 135/85, 130/85, and 130/80 mm Hg.

RESULTS

Among 319 patients, 256 patients (mean age, 51.8 ± 9.7 years; 119 men) with valid HBP measurements and 24-hour ABP measurements were enrolled. The threshold of 130/80 mm Hg showed the highest diagnostic sensitivity (P = 0.001) with diagnostic agreement by Kappa statistics. Using 130/80 mm Hg as a diagnostic threshold of hypertension, the prevalence of masked hypertension was significantly lower than 130/85 and 135/85 mm Hg (7.8, 15.2, and 18.4%, respectively, P = 0.002).

CONCLUSIONS

The present study suggests that lowering the diagnostic thresholds of HBP measurement from 135/85 mm Hg to 130/80 mm Hg may improve diagnostic accuracy for hypertension.

Glomerular hyperfiltration is a predictor of adverse cardiovascular outcomes

The association between glomerular hyperfiltration and cardiovascular events is not well known. To investigate whether glomerular hyperfiltration is independently associated with risk of adverse outcome we analyzed 8794 participants, average age 52 years enrolled in 8 prospective studies. Of these, 89% had hypertension. Using the 5th and 95th percentiles of the age- and sex-specific quintiles of CKD-EPI-calculated estimated glomerular filtration rate (eGFR), we identified three participant groups with low, high and normal eGFR. The ambulatory pulse pressure interval was wider and nighttime blood pressure fall was smaller in both the low and high than in the normal eGFR participants. During a mean follow-up of 6.2 years, there were 722 cardiovascular events. Crude event rates were significantly higher for both high (1.8 per 100-person-year) and low eGFR groups (2.1 per 100 person-year) as compared with group with normal eGFR (1.2 per 100 person-year). In multivariable Cox models including age, sex, average 24-hour blood pressure, smoking, diabetes, and cholesterol, both high eGFR (hazard ratio 1.5 (95% confidence interval 1.2-2.1) and low eGFR (2.0 [1.5-2.6]) participants had a significantly higher risk of cardiovascular events as compared to those with normal eGFR. Addition of body mass index to the multivariable survival model did not change the magnitude of hazard estimates. Thus, glomerular hyperfiltration is a strong and independent predictor of cardiovascular events in a large multiethnic population of predominantly hypertensive individuals. Our findings support a U-shaped relationship between eGFR and adverse outcome.

Effect of Home Blood Pressure on Inducing Remission/Regression of Microalbuminuria in Patients With Type 2 Diabetes Mellitus

BACKGROUND

The Home Blood Pressure for Diabetic Nephropathy study is a prospective observational study conducted to determine the effect of home blood pressure (HBP) on remission/regression of microalbuminuria in patients with type 2 diabetes mellitus (DM).

METHODS

Patients with type 2 DM having microalbuminuria were followed-up for 3 years. Remission of microalbuminuria was defined as shift from microalbuminuria to normoalbuminuria. Regression of microalbuminuria was defined as a 50% reduction in urinary albumin-creatinine ratio from baseline. All measurements of morning and evening HBP were averaged every year and defined as all HBP.

RESULTS

In total, 235 patients were followed up. The 3-year cumulative incidences of remission and regression were 32.3% and 44.7%, respectively. Following analysis of all cases, the degree of decline in all home systolic blood pressure (AHSBP), rather than mean AHSBP, influenced the incidence of remission/regression. There was a strong relationship between the decline in AHSBP during the follow-up period and AHSBP at baseline. Therefore, separate analyses of the patients with AHSBP below 140 mm Hg at baseline were performed, which revealed that mean AHSBP during the follow-up period independently affected the incidence of remission/regression. The hazard ratio for inducing remission/regression was significantly lower in patients with AHSBP during the follow-up period above 130 mm Hg than in those with AHSBP below 120 mm Hg.

CONCLUSIONS

Optimal AHSBP for the induction of remission/regression of microalbuminuria might be below 130 mm Hg. It is required to confirm whether keeping AHSBP below 130 mm Hg leads to subsequent renoprotection or not.

CLINICAL TRIALS REGISTRATION

Trial Number UMIN000000804.

Blood pressure and proteinuria control remains a challenge in patients with type 2 diabetes mellitus and chronic kidney disease: experience from the prospective observational ALICE-PROTECT study

BACKGROUND

Type 2 diabetes (T2DM) is the leading cause of chronic kidney disease (CKD) in western countries. The combination of both increases the risk of end stage renal disease (ESRD), cardiovascular events and all-cause mortality. Early control of blood pressure (BP) and proteinuria (Pu) is crucial to slow down the progression of the CKD and prevent cardiovascular events and mortality. The primary objective of the study was to assess BP and Pu control after a 2-year follow-up in T2DM patients with CKD.

METHODS

Prospective, multicenter, observational study. Overall, 153 French nephrologists included 986 T2DM patients with Pu (≥0.5 g/day) and an eGFR >15 ml/min/1.73 m². Data from 729 patients were available after a 2-year follow-up. BP and Pu control were respectively defined as less than 140/90 mmHg and 0.5 g/day. We also looked at renal and cardiovascular events.

RESULTS

At baseline, 74 % of the patients were male, mean age was 70 years. The mean T2DM duration was 17 years with a mean HbA1c of 7.4 %. All were treated for hypertension and 33 % had a controlled BP; 81 % had dyslipidemia and LDLc was <1 g/L for 54 %; 44 % had retinopathy, 40 % macrovascular complications and 12 % heart failure. Mean Pu was 2 g/day and eGFR 40 ± 20 mL/min/1.73 m², with 13, 18, 32 and 37 % of the patients in respectively stage 2, 3a, 3b and 4 CKD. After two years, 21 % reached the Pu target and 39 % the BP target. The mean eGFR of 40 ± 20.3 ml/min/1.73 m² at baseline dropped to 33.9 ± 22.6 ml/min/1.73 m² by year two (p < 0.001). This corresponded to a mean annual eGFR reduction of 3.2 ml/min/1.73 m². 118 patients presented a renal event (16.2 %): doubling of serum creatinine for 86 patients (11.8 %) and start of dialysis for 72 (9.9 %); 176 patients (24.1 %) developed at least one cardiovascular complication (mainly coronary events and acute heart failure) during the follow-up period, and among these, 50 had also developed renal complications. Sixty patients died, i.e., 8.2 %, 26 patients from cardiovascular causes.

CONCLUSION

Our study highlights that achieving BP and Pu targets remains a major challenge in patients with T2DM and nephropathy. Renal failure emerges as a more frequent event than death.

The effect of low-sodium dialysate on ambulatory blood pressure measurement parameters in patients undergoing hemodialysis

Background

End stage renal disease is related to increased cardiovascular mortality and morbidity. Hypertension is an important risk factor for cardiovascular disorder among hemodialysis (HD) patients. The aim of this study was to investigate the effect of low-sodium dialysate on the systolic blood pressure (SBP) and diastolic blood pressure (DBP) levels detected by ambulatory BP monitoring (ABPM) and interdialytic weight gain (IDWG) in patients undergoing sustained HD treatment.

Patients and methods

The study included 46 patients who had creatinine clearance levels less than 10 mL/min/1.73 m² and had been on chronic HD treatment for at least 1 year. After the enrollment stage, the patients were allocated low-sodium dialysate or standard sodium dialysate for 6 months via computer-generated randomization.

Results

Twenty-four hour SBP, daytime SBP, nighttime SBP, and nighttime DBP were significantly decreased in the low-sodium dialysate group (P<0.05). No significant reduction was observed in both groups in terms of 24-hour DBP and daytime DBP (P=NS). No difference was found in the standard sodium dialysate group in terms of ABPM. Furthermore, IDWG was found to be significantly decreased in the low-sodium dialysate group after 6 months (P<0.001).

Conclusion

The study revealed that low-sodium dialysate leads to a decrease in ABPM parameters including 24-hour SBP, daytime SBP, nighttime SBP, and nighttime DBP and it also reduces the number of antihypertensive drugs used and IDWG.

Managing hypertension with ambulatory blood pressure monitoring

There has been a dramatic shift in the manner in which blood pressure (BP) is measured to provide far more comprehensive clinical information than that provided by a single set of office BP readings. Extensive clinical and epidemiological research shows an important role of ambulatory BP monitoring (ABPM) in the management of hypertensive patients. A 24-h BP profile helps to determine the absence of nocturnal dipping status and evaluate BP control in patients on antihypertensive therapy. The ability to detect white-coat or masked hypertension is enhanced by ambulatory BP monitoring. In 2001, the Center for Medicare and Medicaid Services approved ABPM for reimbursement for the identification of patients with white-coat hypertension. In 2011, the National Institute for Health and Clinical Excellence (NICE) in the UK published guidelines that recommended the routine use of ABPM in all patients suspected of having hypertension. The European Society of Hypertension (ESH) 2013 guidelines also support greater use of ABPM in clinical practice. While the advantages of ABPM are apparent from a clinical perspective, its use should be considered in relation to its cost, the complexity of data evaluation, as well as patient inconvenience. In this review, we evaluate the clinical importance of ABPM, highlighting its role in the current management of hypertension.

Masked Uncontrolled Hypertension in CKD

Masked uncontrolled hypertension (MUCH) is diagnosed in patients treated for hypertension who are normotensive in the clinic but hypertensive outside. In this study of 333 veterans with CKD, we prospectively evaluated the prevalence of MUCH as determined by ambulatory BP monitoring using three definitions of hypertension (daytime hypertension ≥135/85 mmHg; either nighttime hypertension ≥120/70 mmHg or daytime hypertension; and 24-hour hypertension ≥130/80 mmHg) or by home BP monitoring (hypertension ≥135/85 mmHg). The prevalence of MUCH was 26.7% by daytime ambulatory BP, 32.8% by 24-hour ambulatory BP, 56.1% by daytime or night-time ambulatory BP, and 50.8% by home BP. To assess the reproducibility of the diagnosis, we repeated these measurements after 4 weeks. Agreement in MUCH diagnosis by ambulatory BP was 75-78% (κ coefficient for agreement, 0.44-0.51), depending on the definition used. In contrast, home BP showed an agreement of only 63% and a κ coefficient of 0.25. Prevalence of MUCH increased with increasing clinic systolic BP: 2% in the 90-110 mmHg group, 17% in the 110-119 mmHg group, 34% in the 120-129 mmHg group, and 66% in the 130-139 mmHg group. Clinic BP was a good determinant of MUCH (receiver operating characteristic area under the curve 0.82; 95% confidence interval 0.76-0.87). In diagnosing MUCH, home BP was not different from clinic BP. In conclusion, among people with CKD, MUCH is common and reproducible, and should be suspected when clinic BP is in the prehypertensive range. Confirmation of MUCH diagnosis should rely on ambulatory BP monitoring.

MEthods of ASsessing blood pressUre: identifying thReshold and target valuEs (MeasureBP): a review & study protocol

Despite progress in automated blood pressure measurement (BPM) technology, there is limited research linking hard outcomes to automated office BPM (OBPM) treatment targets and thresholds. Equivalences for automated BPM devices have been estimated from approximations of standardized manual measurements of 140/90 mmHg. Until outcome-driven targets and thresholds become available for automated measurement methods, deriving evidence-based equivalences between automated methods and standardized manual OBPM is the next best solution. The MeasureBP study group was initiated by the Canadian Hypertension Education Program to close this critical knowledge gap. MeasureBP aims to define evidence-based equivalent values between standardized manual OBPM and automated BPM methods by synthesizing available evidence using a systematic review and individual subject-level data meta-analyses. This manuscript provides a review of the literature and MeasureBP study protocol. These results will lay the evidenced-based foundation to resolve uncertainties within blood pressure guidelines which, in turn, will improve the management of hypertension.

The complex relationship between CKD and ambulatory blood pressure patterns

Hypertension and CKD frequently coexist, and both are risk factors for cardiovascular events and mortality. Among people with hypertension, the loss of the normal fall in night-time BP, called nondipping, can only be diagnosed by ambulatory BP monitoring (ABPM) and is a risk factor for cardiovascular events. The pathophysiology of nondipping is complex, and CKD is an independent risk factor for nondipping. In fact, nondipping can be seen in as many as 80% of people with CKD. However, the evidence for nondipping as an independent risk factor or causal agent for adverse outcomes in CKD remains mixed. ABPM has been shown to be superior to clinical BP measurement for correlating with end-organ damage and prognosis in CKD. This review covers the evidence for the use of ABPM in CKD, the evidence linking ABPM patterns to outcome in CKD and the evidence for treatment of nondipping in CKD.

Clinical significance of home blood pressure measurements for the prevention and management of high blood pressure

1. Ambulatory blood pressure (ABP) monitoring (M) provides BP information at many points on any particular day during unrestricted routine daily activities, whereas home blood pressure (HBP) monitoring provides a lot of BP information obtained under fixed times and conditions over a long period of time, thus mean values of HBP provide high reproducibility, and thus an overall superiority compared with ABP.  2. HBP is at least equally or better able than ABP to predict hypertensive target organ damage and prognosis of cardiovascular disease.  3. HBPM allows for ongoing disease monitoring by patients, improves adherence to antihypertensive treatment, and can provide health-care providers with timely clinical data and direct and immediate feedback regarding diagnosis and treatment of hypertension.  4. HBPM provides BP information in relation to time; that is, BP in the morning, in the evening and at night during sleep, and it is an essential tool for the diagnosis of white-coat and masked hypertension.  5. HBPM yields minimal alerting affects and no or minimal placebo effect, and can therefore distinguish small, but significant, serial changes in BP. It is thus the most practical method for monitoring BP in the day-to-day management of hypertension. 6. The superiority of HBPM over ABPM and clinic BPM is apparent from almost all practical and clinical research perspectives.

Practical use of home blood pressure monitoring in chronic kidney disease

Despite the availability of blood pressure (BP)-lowering medications and dietary education, hypertension is still poorly controlled in the chronic kidney disease (CKD) population. As glomerular filtration rate declines, the number of medications required to achieve BP targets increases, which may lead to reduced patient adherence and therapeutic inertia by the clinician. Home BP monitoring (HBPM) has emerged as a means of improving diagnostic accuracy, risk stratification, patient adherence, and therapeutic intervention. The definition of hypertension by HBPM is an average BP >135/85 mm Hg. Twelve readings over the course of 3-5 days are sufficient for clinical decision making. Diagnostic accuracy is especially important in the CKD population as approximately half of these patients have either white coat hypertension or masked hypertension. Preliminary data suggest that HBPM outperforms office BP monitoring in predicting progression to end-stage renal disease or death. When combined with additional support such as telemonitoring, medication titration, or behavioral therapy, HBPM results in a sustained improvement in BP control. HBPM must be adapted to provide information on the phenomena of nondipping (absence of nocturnal fall in BP) and reverse dipping (paradoxical increase in BP at night). These diurnal patterns are more prevalent in the CKD population and are important cardiovascular risk factors. Ambulatory BP monitoring provides nocturnal BP readings and unlike HBPM may be reimbursed by Medicare when certain criteria are met. Further studies are needed to determine whether HBPM is cost-effective in the current US healthcare system.

Significance of white-coat and masked hypertension in chronic kidney disease and end-stage renal disease

Hypertension is a frequent and modifiable cardiovascular risk factor with a cyclic relationship with chronic kidney disease (CKD). The diagnosis, treatment, monitoring and control of high blood pressure are all mandatory not only in CKD but also in end-stage renal disease (ESRD). As demonstrated by studies using population and hypertensive patients, white-coat hypertension (WCHT) and masked hypertension (MHT) carry a particular degree of risk. The advantages of ambulatory techniques in the management and prognostic stratification of patients with CKD and ESRD have also been recognized. However, most of the evidence underlines the importance of nocturnal hypertension and neglects WCHT and MHT. The absence of specific reports involving untreated and treated patients hinders the ability to significantly discriminate WCHT from the white-coat effect and MHT from masked uncontrolled hypertension. The heterogeneous definitions that are used add additional difficulty in translating experimental evidence into clinical practice. Reaching a consensus in definitions is mandatory for designing future research. Cross-sectional studies underscore the frequency of misdiagnosis, potentially leading to undertreatment (MHT) and overtreatment (WCHT) in renal disease. The divergent prevalence of WCHT and MHT reported in CKD could be related to the diverse definitions of hypertension and the heterogeneity of the pathologies pooled under the CKD definition. Even in the absence of randomized clinical trials specifically addressing this issue, the scarce longitudinal studies confirm that WCHT carries a risk close to that of sustained normotension, whereas MHT is associated with a risk close or identical to that of sustained hypertension.