Isolated ambulatory hypertension and changes in target organ damage in treated hypertensive patients

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.

[Usefulness of different techniques of blood pressure measurements in 2016]

The management of hypertensive patients is greatly influenced by blood pressure levels and accurate measurement of blood pressure is crucial in this context. Mercury sphygmomanometer has been progressively replaced by more precise oscillometric devices that can be widely used in the clinic and ambulatory setting. The purpose of this review was to detail the different methods for evaluating blood pressure, and to refine their indications and clinical benefit. Office blood pressure measurement has a great variability and should follow a strict protocol to give consistent results. National and international guidelines focus on blood pressure measurement in the ambulatory setting. When used by trained patients, home blood pressure monitoring is reproducible and can provide substantial prognostic information, even if ambulatory blood pressure monitoring remains the gold standard. The role of central blood pressure and pulse wave velocity monitoring in the therapeutic strategy of hypertension needs further assessment.

White coat effect and masked uncontrolled hypertension in treated hypertensive-diabetic patients: Prevalence and target organ damage

BACKGROUND

The association between hypertensive phenotypes of controlled hypertension (CH), white-coat effect (WCE), masked uncontrolled hypertension (MUH) and sustained hypertension (SH) with target organ damage have not been clearly established in diabetic hypertensive treated patients. The present study aims to evaluate the prevalence of the four phenotypes considering the current cut-off points for office and 24 h-ambulatory blood pressure monitoring (ABPM) and the association with left ventricle hypertrophy (LVH), diastolic function and nephropathy.

METHODS

Cross-sectional study with 304 patients on anti-hypertensive treatment aged 57.6 ± 6.1 years, who were submitted to ABPM and echocardiography. They were classified into CH (normal office BP and ABPM), WCE (high office BP and normal ABPM), MUH (normal office BP and high ABPM), and SH (high office BP and ABPM).

RESULTS

Median HbA1c and diabetes duration were 7.9% (6.8-9.2), and 10 years (5-16), respectively. Prevalences of CH, WCE, MUH and SH were 27.3%, 17.1%, 18.8%, and 36.8%. MUH prevalence was higher than previously described. There was a significant increasing trend across the four groups in variables related to LVH (P < 0.001 for trend). There was not a clear "dose-response" relationship of the four hypertensive phenotypes with nephropathy and diastolic function.

CONCLUSION

The use of ABPM beyond the traditional cardiovascular risk stratification tools has limitations, but is still useful in high-risk patients. Longitudinal studies could better evaluate the role of the use of ABPM in this scenario. Cut-off points for normality of office and ABPM influence the prevalences of WCH and MUH.

Relationship of short-term blood pressure variability with carotid intima-media thickness in hypertensive patients

Background

High blood pressure (BP) is among significant risk factor for stroke and other vascular occurrences, it experiences nonstop fluctuations over time as a result of a complex interface among cardiovascular control mechanisms. Large blood pressure variability (BPV) has been proved to be promising in providing potential regulatory mechanisms of the cardiovascular system. Although the previous studies also showed that BPV is associated with increased carotid intima-media thickness (IMT) and plaque, whether the correlation between variability in blood pressure and left common carotid artery-intima-media thickness (LCCA-IMT) is stronger than right common carotid artery-intima-media thickness (RCCA-IMT) remains uncertain in hypertension.

Methods

We conduct a study (78 hypertensive subjects, aged 28–79) to evaluate the relationship between BPV and carotid intima-media thickness in Shenzhen. The blood pressure was collected using the 24 h ambulatory blood pressure monitoring, and its variability was evaluated using standard deviation (SD), coefficient of variation (CV), and average real variability (ARV) during 24 h, daytime and nighttime. All the IMT measurements are collected by ultrasound.

Results

As the results showed, 24 h systolic blood pressure variability (SBPV) evaluated by SD and ARV were significantly related to LCCA-IMT (r¹ = 0.261, P = 0.021; r¹ = 0.262, P = 0.021, resp.). For the daytime diastolic blood pressure variability (DBPV), ARV indices were significantly related to LCCA-IMT (r¹ = 0.239, P = 0.035), which differed form BPV evaluated by SD and CV. For the night time, there is no significant correlation between the BPV and IMT. Moreover, for all the subjects, there is no significant correlation between the BPV and RCCA-IMT/number of plaques, whereas, the SD, CV, and ARV of daytime SBP showed a positive correlation with LCCA-IMT (r¹ = 0.312, P = 0.005; r¹ = 0.255, P = 0.024; r¹ = 0.284, P = 0.012, resp.). Moreover, the ARV of daytime SBPV, 24 h SBPV and nighttime DBPV showed a positive correlation with the number of plaques of LCCA (r¹ = 0.356, P = 0.008; r¹ = 0.297, P = 0.027; r¹ = 0.278, P = 0.040, resp.). In addition, the number of plaques in LCCA had higher correlation with pulse pressure and diastolic blood pressure than that in RCCA. And multiple regression analysis indicated LCCA-IMT might not only be influenced by age or smoking but also by the SD index of daytime SBPV (p = 0.035).

Conclusions

The results show that SBPV during daytime and 24 h had significant correlation with IMT, for the hypertensive subjects from the southern area of China. Moreover, we also found the daytime SBPV to be the best predictor for the progression of IMT in multivariate regression analysis. In addition, the present study suggests that the correlation between BPV and left common carotid artery—intima-media thickness/number of plaques is stronger than right common carotid artery-intima-media thickness/number of plaques.

Association of isolated systolic, isolated diastolic, and systolic-diastolic masked hypertension with carotid artery intima-media thickness

Masked hypertension (MH) is associated with advanced target organ damage. However, patients with MH constitute a group of individuals with heterogeneous characteristics concerning their ambulatory blood pressure (BP) status. The aim of this study was to evaluate the association of isolated systolic MH, isolated diastolic MH, and systolic/diastolic MH with carotid artery intima-media thickness (CIMT). A total of 101 patients with MH underwent carotid artery ultrasonographic measurements. The patients were divided into three groups according to office and daytime BP values: isolated systolic MH, isolated diastolic MH, and systolic/diastolic MH. Patients with isolated systolic (n=36) (0.771 mm) and systolic/diastolic MH (n=37) (0.775 mm) had significantly (P<.05) higher CIMT values than those with isolated diastolic MH (n=28) (0.664 mm), even after adjustment for baseline characteristics and risk factors. Patients with isolated systolic and systolic/diastolic MH presented significantly higher CIMT values compared with patients with isolated diastolic MH.

Left ventricular hypertrophy and chronic fluid overload in peritoneal dialysis patients

PURPOSE

Cardiovascular disease is the leading cause of mortality in dialysis patients with left ventricular hypertrophy (LVH) being an important predictor of mortality. We wanted to determine the prevalence of LVH in peritoneal dialysis (PD) patients and factors contributing to it.

METHODS

This is a cross-sectional study assessing LVH using echocardiogram in PD patients. Left ventricular mass index (LVMI) was calculated to determine LVH. Chronic fluid overload (overhydration) was assessed using the body composition monitor, and blood pressure (BP) was measured using 24-h ambulatory BP monitoring.

RESULTS

Thirty-one patients (21 females:10 males, 48.97 ± 14.50 years and dialysis vintage 40.0 ± 28.9 months) were studied. More than two-thirds (77.4 %) were hypertensive, and a third (35.5 %) were diabetic. Baseline data included mean serum albumin (37.34 ± 4.43 g/l), weekly Kt/V (2.02 ± 0.23), residual renal function of 68 (0-880) ml and ultrafiltration of 1,606.9 ± 548.6 ml. Majority of patients (80.6 %) had LVH on echocardiogram with LVMI of 136.5 ± 37.8 g/m(2) and overhydration of 2.23 ± 1.77 l. Average systolic BP, diastolic BP and mean arterial pressure were 141.2 ± 23.3, 90.8 ± 19.7 and 107.6 ± 19.6 mmHg, respectively. Patients with LVH had a lower serum albumin (p = 0.003), were more overhydrated (p = 0.010) and were on higher number of anti-hypertensive agents (p ≤ 0.001). Predictors of LVMI were overhydration (p = 0.002), the presence of diabetes (p = 0.008) and the number of anti-hypertensive agents used (p = 0.026). However, overhydration (p = 0.007) was the main predictor of LVH on multivariate analysis.

CONCLUSION

Overhydration is strongly associated with LVH in PD patients.

Blood pressure measurement: clinic, home, ambulatory, and beyond

Blood pressure traditionally has been measured in the clinic setting using the auscultatory method and a mercury sphygmomanometer. Technologic advances have led to improvements in measuring clinic blood pressure and allowed for measuring blood pressures outside the clinic. This review outlines various methods for evaluating blood pressure and the clinical utility of each type of measurement. Home blood pressures and 24-hour ambulatory blood pressures have improved our ability to evaluate the risk of target-organ damage and hypertension-related morbidity and mortality. Measuring home blood pressures may lead to more active participation in health care by patients and has the potential to improve blood pressure control. Ambulatory blood pressure monitoring enables measuring nighttime blood pressures and diurnal changes, which may be the most accurate predictors of risk associated with elevated blood pressure. Additionally, reducing nighttime blood pressure is feasible and may be an important component of effective antihypertensive therapy. Finally, estimating central aortic pressures and pulse wave velocity are 2 of the newer methods for assessing blood pressure and hypertension-related target-organ damage.

Masked hypertension: evidence of the need to treat

The diagnosis of masked hypertension has been made easier with the widespread availability of home blood pressure monitoring devices with levels of accuracy comparable to ambulatory blood pressure monitoring. The negative impact of masked hypertension on cardiovascular morbidity and mortality is evidenced by numerous well-designed clinic-based and population-based studies. The relationship of masked hypertension and target organ damage is also well documented. These two factors, combined with the robust evidence of reduced cardiovascular morbidity and mortality achieved with blood pressure treatment, makes the argument for actively identifying patients with masked hypertension and prescribing treatment similar to that for patients with sustained hypertension. In this paper, we review the evidence for the cardiovascular prognosis of masked hypertension compared with sustained hypertension, we review its impact on target organ damage, we propose an algorithm for the treatment of patients with masked hypertension, and we point out the pitfalls in adopting such an approach.

The association of masked hypertension in treated type 2 diabetic patients with carotid artery IMT

OBJECTIVES

To evaluate the association of masked hypertension (MH) in treated type 2 diabetic patients without history of cardiovascular disease with carotid artery target organ damage.

METHODS

Sixty-four type 2 diabetic patients treated for hypertension with office BP below 140/90 mm Hg were examined by 24-h BP monitoring and carotid sonography. MH was diagnosed if daily mean ambulatory BP was >or=135/85 mm Hg. The association of MH with carotid artery parameters was evaluated.

RESULTS

The average age of patients was 62+/-5 years. Twenty-four patients had MH (37.5%). Carotid artery IMT was 0.74+/-0.08 mm in patients with MH and 0.69+/-0.06 mm without MH (p=0.03). The distensibility of common carotid artery was 0.24+/-0.07 mmHg(-1) in patients with MH and 0.29+/-0.1mm Hg(-1) without MH (p=0.14). After adjustment for age, gender, smoking, duration of diabetes, BMI and clinic blood pressure (BP) values the association of MH with carotid artery IMT was sustained.

CONCLUSION

Masked hypertension in treated type 2 diabetic patients is associated with carotid artery IMT.

Role of ambulatory and home blood pressure recording in clinical practice

Because of shortcomings of the office blood pressure (BP) measurement in individuals with hypertension (eg, white coat and masked hypertension effects, terminal digit bias, and large variability in BP among a small number of readings), use of out-of-office blood pressure measurements has become more common in clinical practice. The presence of the syndromes of white-coat and masked hypertension creates the concern that the office BP measurements are not reflective of an individual patient's true BP values. Home (or self) and ambulatory BP assessments have been used in numerous types of clinical trials and have demonstrated their usefulness as reliable research and clinical tools. In this article, we review the recent literature on the benefits and limitations of home (self) and ambulatory monitoring of the BP in clinical practice. In particular, how it relates to the diagnosis of patients with various presentations of hypertension and to cardio-vascular outcomes with long-term follow-ups of population cohorts.

Home blood pressure monitoring in clinical practice: a review

Home blood pressure monitoring is a convenient and inexpensive technique to monitor blood pressure in hypertensive patients. There are convincing data that home blood pressure monitoring is a good predictor of future cardiovascular risk, perhaps better than office blood pressure. Home blood pressure measurement can be standardized using validated instruments and systematic protocols; normative criteria have established home blood pressure >135/85 mm Hg as hypertensive. Home blood pressure monitoring has been shown to improve compliance and blood pressure control, and to reduce health care costs. Ongoing studies are evaluating management of hypertension based on home blood pressure readings compared with traditional office-based readings. Home blood pressure monitoring is particularly useful for evaluation of white coat hypertension and masked hypertension. In this article, we discuss the methodology for measuring blood pressure at home, its comparison to the other measurement techniques, the advantages and disadvantages, cost benefit analyses, and ongoing clinical trials to help define the role of home blood pressure monitoring in the clinical management of hypertension.

Vascular permeability, blood pressure, and organ damage in primary hypertension

Sub-clinical organ damage is a strong independent predictor of cardiovascular mortality in primary hypertension, and its changes over time parallel those in risk of cardiovascular events. A better understanding of the pathogenetic mechanisms underlying the development of target organ damage may help us devise more effective therapeutic strategies. We therefore investigated the relationship between the presence of organ damage and some of its potential determinants, such as blood pressure severity and early atherosclerotic abnormalities. Thirty-seven untreated, non-diabetic hypertensive patients were enrolled. Target organ damage was assessed by albuminuria and left ventricular mass index; systemic vascular permeability was evaluated by transcapillary escape rate of albumin (TERalb); and blood pressure was measured by 24h ambulatory blood pressure monitoring. The albumin-to-creatinine ratio and left ventricular mass index were directly related to TERalb (r = 0.48, p = 0.003 and r = 0.39, p < 0.020, respectively) and 24-h systolic blood pressure values (r = 0.54, p < 0.001; r = 0.60, p < 0.001). The simultaneous occurrence of increased blood pressure load and TERalb was associated with higher left ventricular mass index values (p = 0.012) and entailed an increased risk of having at least one sign of damage (chi2 = 17.4; p < 0.001). Logistic regression analysis showed that the risk of presenting at least one sign of organ damage increased more than ten-fold when TERalb was above the median and more than five-fold with each 10 mmHg increase in 24-h systolic blood pressure. Blood pressure load and vascular permeability are potentially modifiable factors that are independently associated with the occurrence of sub-clinical signs of renal and cardiac damage in hypertensive patients.

Masked hypertension, a review of the literature

Masked hypertension (blood pressure that is normal in the physicians' office but elevated elsewhere) is a common phenomenon as prevalence among studies varies from 8 to 45% and is seen at all ages. large discrepancies, however, exist between studies that have dealt with masked hypertension. It is of high clinical importance as it is associated with higher target organ damage as compared with sustained normotension. Therefore more research should be determined. This paper provides an overview of current literature to improve knowledge about masked hypertension and about the cause of this phenomenon. In addition it provides some questions, which need to be answered for performing appropriate research into this subject in future.

Reverse white-coat effect as an independent risk for left ventricular concentric hypertrophy in patients with treated essential hypertension

Recent studies have shown that the converse phenomenon of white-coat hypertension called 'reverse white-coat hypertension' or 'masked hypertension' is associated with poor cardiovascular prognosis. We assessed the hypothesis that this phenomenon may specifically influence left ventricular (LV) structure in treated hypertensive patients. A total of 272 outpatients (mean age, 65 years) with chronically treated essential hypertension and without remarkable white-coat effect were enrolled. Patients were classified into two groups according to office and daytime ambulatory systolic blood pressure (SBP); that is subjects without (Group 1: office SBP > or =daytime SBP, n=149) and with reverse white-coat effect (Group 2: office SBP<daytime SBP, n=123). LV mass index and relative wall thickness were echocardiographically determined. In all subjects, LV mass index and relative wall thickness were positively correlated with daytime and 24-h SBP, but not with office SBP. In addition, these two indices were inversely correlated with office--daytime SBP difference. LV mass index (136+/-31 and 115+/-28 g/m(2), mean+/-s.d.) and relative wall thickness (0.49+/-0.09 and 0.46+/-0.07) were significantly greater in Group 2 than in Group 1. As for LV geometric patterns, Group 2 had a significantly higher rate of concentric hypertrophy compared with Group 1 (48 and 28%). Multivariate analyses revealed that the presence of reverse white-coat effect was a predictor for LV concentric hypertrophy, independent of age, sex, hypertension duration, antihypertensive treatment and ambulatory blood pressure levels. Our findings demonstrate that reverse white-coat effect is an independent risk factor for LV hypertrophy, especially concentric hypertrophy, in treated hypertensive patients.

Effects of angiotensin II receptor blockade-based therapy with losartan on left ventricular hypertrophy and geometry in previously treated hypertensive patients

BACKGROUND

The 2003 European Society of Hypertension/European Society of Cardiology (ESH/ESC) guidelines recommend angiotensin II receptor antagonists (AIIRAs) as a first-line therapy in hypertensives with left ventricular hypertrophy (LVH).

AIM

We investigated the long-term effects of an AIIRA-based therapy on left ventricular (LV) structure and geometry in previously, unsatisfactorily treated essential hypertensive patients.

METHODS

Sixty-eight consecutive patients referred to our hypertension hospital outpatient clinic with: (i) LVH (LV mass index, LVMI 51 g/m(2.7) in men and 47 g/m(2.7) in women), (ii) uncontrolled clinic blood pressure (BP140 and/or 90 mmHg) and (iii) antihypertensive therapy not including angiotensin-converting enzyme (ACE) inhibitors or AIIRAs were selected for this study. Two-dimensionally guided M-mode echocardiograms were carried out at baseline and after 6, 12, 18 and 24 months of follow-up. In all patients, losartan (50-100 mg/day, mean dose 82 mg/day) was added as first step to the previous therapy. Additional drugs, tailored to the single patient, were added, if necessary, to achieve target BP values (<140/90 mmHg).

RESULTS

Overall, 59 patients completed the study with the primary efficacy measurements (LVMI) at all appropriate times. A significant reduction in both clinic systolic BP and diastolic BP was found across the entire period of study respect to baseline (-17/10, -22/12, -24/13 and -26/14 mmHg at 6, 12, 18 and 24 months, p < 0.001 respectively), leading to target clinic BP in 75.6% of cases. LVMI was significantly lower after 1 year of treatment (-11 +/- 12%, p < 0.05) with a further significant reduction at the end of treatment (-22 +/- 18%, p < 0.01). The proportion of patients achieving normalization of LVMI was 47.4% and more importantly, the prevalence of concentric LVH fell from 38.9% to 6.7% (p < 0.01).

CONCLUSIONS

Our findings indicate that long-term intensive treatment based on the AIIRA losartan induced a normalization of LVH in about 50% of patients and more importantly caused an almost complete regression of concentric LVH, the most dangerous adaptive pattern. The transition from concentric to normal or eccentric LV geometry may have in these high-risk patients a favourable prognostic implication in addition to the recognized positive effect of reducing LVMI.

Masked hypertension: a common but insidious presentation of hypertension

A patient has masked hypertension when his office blood pressure is less than 140/90 mmHg but his ambulatory or home blood pressure readings are in the hypertensive range. Several recent studies have demonstrated that cardiovascular risk is similar between those with masked hypertension and those with sustained hypertension. The prevalence of masked hypertension in Canada is not known, but data from other countries suggest rates greater than 8%. Physicians need to use careful clinical judgment to identify and treat subjects with masked hypertension. The present review discusses masked hypertension, its importance to clinical practice and some aspects of patient management.

Ambulatory blood pressure variability and brachial-ankle pulse wave velocity in untreated hypertensive patients

Blood pressure (BP) variability is estimated as the standard deviation of 24-h ambulatory BP. The present study was performed to determine the effect of the mean 24-h ambulatory BP values and standard deviations on arterial wall stiffness assessed by brachial-ankle pulse wave velocity (baPWV). Brachial-ankle pulse wave velocity, carotid intima-media thickness (IMT), urinary albumin excretion (UAE) and 24-h ambulatory BP were measured before the start of antihypertensive therapy in 203 newly diagnosed hypertensive patients (53.3+/-0.7 years old; clinic systolic/diastolic BP: 154+/-1/98+/-1 mm Hg), and univariate and multivariate regression analyses of these clinical and biological parameters were performed. Univariate regression analyses revealed a significant association between mean baPWV values and the standard deviations of ambulatory systolic/diastolic BP. Mean ambulatory systolic/diastolic BP values were also associated with UAE, and the standard deviations of ambulatory systolic BP were associated with maximum carotid IMT. Quintile analyses showed that patients with a mean 24-h ambulatory mean BP value and standard deviation below 110 and 20 mm Hg, respectively, had the lowest baPWV. Moreover, the multivariate regression analyses confirmed a significant correlation between baPWV and the standard deviation of 24-h ambulatory systolic BP. In conclusion, untreated hypertensive patients with a higher 24-h ambulatory systolic BP variability had stiffer arterial walls. Ambulatory systolic BP variability may be involved in stiffening of the arteries of hypertensive patients.

Applications of 24-hour Noninvasive Ambulatory Blood Pressure Monitoring

Casual blood pressure (CBP) measurements using a standard sphygmomanometer have traditionally constituted the principal modality for the assessment and management of hypertension. However, CBP measurement has shortcomings. Ambulatory blood pressure monitoring (ABPM) provides abundant information on blood pressure (BP), including heart rate, all BP readings for test periods, BP average, BP variability, BP load, load index, distribution pattern of BP, reduction percentage of BP, trough/peak ratio, and summary statistics for overall 24-hour, daytime and nighttime periods. Over the last three decades, ABPM has evolved from a research device to an established and valuable clinical tool for assessment and management of hypertension. This technology has been proven to be useful in terms of the distribution pattern of BP, characterization of BP profiles in normotensive and hypertensive patients, evaluation of patients with mild or labile hypertension, physiologic and psychologic factors for fluctuation of BP, load index study, study of white coat hypertension, etiology of hypertension, prognosis of hypertension, and assessment of antihypertensive management. Nevertheless, the technology remains underused due to lack of insurance reimbursement in most countries. Accordingly, insurance reimbursement is crucial to promote increased utility of ABPM. Clinicians should be familiar with the role of this technology in the care of patients with abnormal BP. This review is an attempt to increase clinicians' understanding of ABPM and the appropriate use of this technology.