Subclinical Organ Damage in White-Coat Hypertension: The Possible Role of Cystatin C

Serum neutrophil gelatinase-associated lipocalin and cystatin C is associated with blood pressure in ex-preterm children and adolescents

BACKGROUND

As preterm birth is a risk factor for hypertension (HTN), biomarkers for early prediction of HTN in childhood is an emerging need. The aims of the study were to evaluate serum biomarkers in ex-preterm children and examine for associations with office peripheral and central SBP (cSBP), ambulatory BP parameters and pulse wave velocity (PWV).

METHODS

This case-control study included children and adolescents born prematurely (ex-preterms) and at full term (controls). All participants underwent office and ambulatory BP monitoring, assessment of cSBP, PWV and serum biomarkers at the same visit. Neutrophil gelatinase-associated lipocalin (NGAL), matrix metalloproteinase-2, metalloproteinase-9 (MMP-2, MMP-9) and Cystatin C (CysC) were measured using ELISA.

RESULTS

The study population included 52 ex-preterm individuals and 26 controls. Mean age was 10.7 ± 3.6 years. NGAL, MMP-2, MMP-9, and CysC levels were similar between the ex-preterm and the control group. In the ex-preterm group, NGAL is associated with office SBP z score (β = 1.007, 95% CI 1.001-0.014, P = 0.049), CysC with office DBP z score (β = 1.003, 95% CI 1.001-0.005, P = 0.018) and cSBP z score (β = 1.003, 95% CI 1.001-0.005, P = 0.006) independently of age, sex and BMI z score. Among ex-preterm children and adolescents 17% had ambulatory HTN and 31% had white-coat HTN. NGAL levels were higher in ex-preterm children with WCH compared with children with normal BP [57.9 (IQR 50.8) versus 34.6 (IQR 46.2)], P = 0.018].

CONCLUSION

WCH is common in ex-preterm children and adolescents and is associated with higher NGAL levels and CysC presents positive association with cSBP. The findings in this study provides preliminary evidence that NGAL and CysC may have a role in predicting the risk of developing hypertension later in life. Further studies are warranted.

Association between nocturnal blood pressure phenotype and adverse cardiovascular prognosis in patients with coronary heart disease and hypertension

Nocturnal blood pressure and nighttime dipping patterns are associated with the occurrence of cardiovascular events. However, there is few research on whether riser pattern is associated with the poor prognosis of patients with coronary heart disease (CHD) and hypertension independent of nighttime systolic blood pressure (SBP). This prospective and observational clinical study included 568 hospitalized patients with CHD and hypertension. All patients underwent 24-h ambulatory blood pressure (BP) monitoring during their hospitalization. Multivariate adjusted Cox proportional hazard models were utilized to examine the associations of nocturnal blood pressure and dipping status with primary endpoint events. Additionally, Harrell's C-statistics were employed to compare the discriminative ability of each model. During the 1-year follow-up period, 64 (11.3%) primary endpoint events were recorded, including 55 (9.7%) atherosclerotic cardiovascular disease (ASCVD) events. After adjusting for demographic and clinical risk variables, nighttime SBP was significantly related to the risk of incident primary endpoint events [per 20 mm Hg increase: hazard ratio (HR) = 1.775, 95% confidence interval (CI) 1.256-2.507]. The riser pattern group exhibited a significantly higher risk for primary endpoint events compared to the dipper pattern group, even after adjusting for office SBP (HR: 2.687, 95% CI: 1.015-7.110, p = .047). Furthermore, the addition of nighttime SBP or dipping status to the base model yielded statistically significant increments in C-statistic values (p = .036 and p = .007). However, adding both nighttime SBP and dipping status did not significantly enhance the model's performance in predicting the risk of primary endpoint events and ASCVD events according to the C-index (p = .053 and p = .054), which meant that the riser pattern group did not exhibit a significantly higher risk for primary endpoint events compared to the dipper pattern group after adjusting for nighttime SBP. In conclusion, nocturnal SBP and riser pattern demonstrated an association with adverse prognosis in patients with CHD and hypertension. Notably, nocturnal SBP proved to be a more reliable predictor than dipping status.

White coat hypertension is another clinical characteristic of patients with inflammatory bowel disease: A cross-sectional study

In this cross-sectional study, our aim was to analyze association of ambulatory blood pressure monitoring (ABPM) values with pulse wave velocity (PWV) in inflammatory bowel disease (IBD) patients as well as the prevalence and characteristics of white coat hypertension (WCH) in this group of patients with chronic inflammation and high prevalence of anxiety. We enrolled 120 consecutive IBD patients (77 Crohn´s disease; 43 ulcerative colitis) who were not treated with antihypertensive drugs without cardiovascular, cerebrovascular and renal morbidity. Office blood pressure, ABPM, and PWV were measured with Omrom M6, SpaceLab 90207, and Arteriograph, respectively. The prevalence of true normotension, sustained hypertension and WCH was analyzed in IBD patients. WCH was found in 27.5% patients. IBD-WCH patients had significantly lower prevalence of traditional risk factors than general WCH subjects. PWV and augmentation index (AIx) values were higher in WCH than in true normotensive patients. When adjusted for age and duration of IBD, only PWV was a positive predictor of WCH, and patients with higher PWV and longer disease duration had OR´s for WCH of 0.69 and 2.50, respectively. IBD patients had significantly higher prevalence of WCH and higher PWV values than healthy control patients. WCH is highly prevalent in IBD patients but IBD-WCH patients have lower frequency of traditional cardiovascular risk factors than general WCH population. Our results suggest that WCH could be considered as another clinical characteristic of IBD which is associated with increased arterial stiffness and those patients should be monitored more closely.

Pressure overload promotes cystatin C secretion of cardiomyocytes to regulate the MAPK signaling pathway and mediate cardiac hypertrophy

BACKGROUND

This study aimed to compare serum cystatin C (CysC) levels between hypertensive and non-hypertensive patients, and to explore the correlation between serum CysC and left ventricular hypertrophy (LVH). We also investigated the effects of pressure overload on cardiac expression and secretion of CysC, and explored the direct effect of CysC on the hypertrophy of primary cardiomyocytes.

METHODS

Serum CysC was compared in patients with hypertension (634 patients) and those without hypertension (411 patients), and the correlation between serum CysC levels and LVH was explored. A transverse aortic constriction (TAC) mouse model and a mechanical stretch model of primary cardiomyocytes and fibroblasts were developed to compare cardiac expression and secretion of CysC under pressure overload. After intervention with exogenous CysC, we compared the cross-sectional area of primary cardiomyocytes, cardiac hypertrophy-associated gene expression, and phosphorylation of the MAPK signaling pathway.

RESULTS

In chronic kidney disease (CKD) stage 1 patients, serum CysC was higher in hypertensive patients independent of renal function. Serum CysC elevation was an independent predictor of LVH after correction for endogenous creatinine clearance rate (eCCr), left ventricular ejection fraction (LVEF), and NT-proBNP. Cardiac levels of CysC in TAC mice were elevated. CST3 gene expression was upregulated, and both intracellular and culture supernatant CysC levels increased after mechanical stretch of primary cardiomyocytes. After intervention with exogenous CysC, the cross-sectional area of primary cardiomyocytes increased, as well as the gene expression of Nppa, Nppb, and Myh7, and the phosphorylation of ERK, p38, and TAK1.

CONCLUSIONS

Serum CysC levels were higher in hypertensive patients, and serum CysC elevation was an independent predictor of LVH after correction for eCCr. Pressure overload induced greater cardiomyocyte secretion of CysC. Exogenous CysC can enter cardiomyocytes, having a pro-hypertrophic effect on primary cardiomyocytes through regulation of the MAPK signaling pathways.

Cystatin C as a biomarker of chronic kidney disease: latest developments

INTRODUCTION

Chronic kidney disease (CKD) is common, occurring in over 10% of individuals globally, and is increasing in prevalence. The limitations of traditional biomarkers of renal dysfunction, such as serum creatinine, have been well demonstrated in the literature. Therefore, augmenting clinical assessment with newer biomarkers, such as serum cystatin C, has the potential to improve disease monitoring and patient care.

AREAS COVERED

The present paper assesses the utility and limitations of serum cystatin C as a biomarker for CKD in light of the current literature.

EXPERT OPINION

Serum cystatin C has been well established as an early and accurate biomarker of CKD that is particularly helpful in patients for whom creatinine is an inadequate marker or for whom more cumbersome methods of glomerular filtration rate (GFR) measurement are impractical. Current research questions are no longer focused on if, but rather when and how often cystatin C should be used in the evaluation of CKD patients. However, transition of all reagents and estimated GFR equations to the newly established International Standard is critical for developing generalizable data.

Blood Pressure Measurement and Treatment Decisions

White-coat and masked hypertension are important hypertension phenotypes. Out-of-office blood pressure measurement is essential for the accurate diagnosis and monitoring of these conditions. This review summarizes literature related to the detection and diagnosis, prevalence, epidemiology, prognosis, and treatment of white-coat and masked hypertension. Cardiovascular risk in white-coat hypertension appears to be dependent on the presence of coexisting risk factors, whereas patients with masked hypertension are at increased risk of target organ damage and cardiovascular events. There is an unmet need for robust data to support recommendations around the use of antihypertensive treatment for the management of white-coat and masked hypertension.

Expert panel consensus recommendations for ambulatory blood pressure monitoring in Asia: The HOPE Asia Network

Hypertension is an important public health issue because of its association with a number of significant diseases and adverse outcomes. However, there are important ethnic differences in the pathogenesis and cardio-/cerebrovascular consequences of hypertension. Given the large populations and rapidly aging demographic in Asian regions, optimal strategies to diagnose and manage hypertension are of high importance. Ambulatory blood pressure monitoring (ABPM) is an important out-of-office blood pressure (BP) measurement tool that should play a central role in hypertension detection and management. The use of ABPM is particularly important in Asia due to the specific features of hypertension in Asian patients, including a high prevalence of masked hypertension, disrupted BP variability with marked morning BP surge, and nocturnal hypertension. This HOPE Asia Network document summarizes region-specific literature on the relationship between ABPM parameters and cardiovascular risk and target organ damage, providing a rationale for consensus-based recommendations on the use of ABPM in Asia. The aim of these recommendations is to guide and improve clinical practice to facilitate optimal BP monitoring with the goal of optimizing patient management and expediting the efficient allocation of treatment and health care resources. This should contribute to the HOPE Asia Network mission of improving the management of hypertension and organ protection toward achieving "zero" cardiovascular events in Asia.

White coat syndrome and its variations: differences and clinical impact

Hypertension is closely linked to increased cardiovascular risk and development of target organ damage (TOD). Therefore, proper clinical follow-up and treatment of hypertensive subjects are mandatory. A great number of individuals present a variation on blood pressure (BP) levels when they are assessed either in the office or in the out-of-office settings. This phenomenon is defined as white coat syndrome - a change in BP levels due to the presence of a physician or other health professional. In this context, the term "white coat syndrome" may refer to three important and different clinical conditions: 1) white coat hypertension, 2) white coat effect, and 3) masked hypertension. The development of TOD and the increased cardiovascular risk play different roles in these specific subgroups of white coat syndrome. Correct diagnose and clinical guidance are essential to improve the prognosis of these patients. The aim of this review was to elucidate contemporary aspects of these types of white coat syndrome on general and hypertensive population.

Effect of white-coat hypertension on arterial stiffness: A meta-analysis

BACKGROUND

White-coat hypertension (WCH) is a debatable risk factor of cardio-cerebrovascular diseases and the current study results on the association between WCH and arterial stiffness are inconsistent. The aim was to investigate the effect of WCH on arterial stiffness using meta-analysis.

METHODS

Based on prespecified search strategies and inclusion criteria, Medline, Embase, Web Of Science, Cochrane Library, and BioSciences Information Service Preview databases were reviewed. A total of 20 studies involving 1538 WCH patients and 3582 normotensives (NT) were included. Literatures were screened for data extraction and quality assessment. Overall analysis and subgroup analysis were conducted in RevMan version 5.3 and Stata version 14.0 software.

RESULTS

Overall analysis showed that carotid-femoral pulse wave velocity (cf-PWV) was significantly higher in WCH group than in the NT group (P < .00001, 95% CI: 0.79-3.26). Subgroup analysis showed that in adults, cf-PWV was significantly higher in the WCH patients than in the NT subjects (P<.001, 95% CI: 0.46-0.87), while in juveniles, cf-PWV was comparable between the WCH group and the NT group (P = .25, 95% CI: -0.39 to 0.61).

CONCLUSION

This meta-analysis showed that WCH may increase arterial stiffness in adult population.