Day-night blood pressure variations: mechanisms, reproducibility and clinical relevance

Anti-hypertensive effect of a novel angiotensin II receptor neprilysin inhibitor (ARNi) -S086 in DSS rat model

Introduction

Angiotensin receptor-neprilysin inhibitor (ARNi), comprised of an angiotensin receptor blocker (ARB) and a neprilysin inhibitor (NEPi), has established itself as a safe and effective intervention for hypertension. S086 is a novel ARNi cocrystal developed by Salubris for the treatment of heart failure and hypertension.

Methods

Dahl Salt Sensitive (DSS) hypertensive rat model and telemetry system were employed in this study to investigate the anti-hypertensive efficacy of S086 and compare it with the first ARNi-LCZ696.

Results and discussion

The study showed that oral administration of S086 dose-dependently lowered blood pressure (P < 0.001). The middle dosage of S086 (23 mg/kg) exhibited efficacy comparable to LCZ696 (68 mg/kg), while also demonstrating superiority at specific time points (P < 0.05). Notably, water consumption slightly decreased post-treatment compared to the vehicle group. Furthermore, there were significant increases in natriuresis and diuresis observed on the first day of treatment with 23 mg/kg and 68 mg/kg S086 (P < 0.001). However, over the course of treatment, the effects in all treatment groups gradually diminished. This study demonstrates the anti-hypertensive efficacy of S086 in DSS hypertensive rat model, offering promising avenues for the clinical development of S086 as a hypertension treatment.

Subjective social status and nocturnal blood pressure dipping

OBJECTIVE

Low social status has been linked to cardiovascular disease. Subjective social status (SSS), which represents one's perceived position in a social hierarchy, has been suggested to predict health outcomes beyond objective measures of socioeconomic status. The present study examined if lower SSS is related to reduced nocturnal blood pressure (BP) dipping, a risk factor for cardiovascular disease.

METHODS

In this cross-sectional study, a community sample of 53 healthy adults underwent 24-h ambulatory BP monitoring. All participants provided information on SSS and objective measures of socioeconomic status (i.e., education, occupation, and income). SSS was measured in comparison to others in the country (national SSS) as well as in comparison to one's social environment (local SSS) using the German versions of the MacArthur Scales.

RESULTS

Analyses found that participants with low local SSS exhibited attenuated nocturnal diastolic blood pressure dipping (β = 0.29, 95% CI [0.01, 0.57], p = .043) and mean arterial pressure dipping (β = 0.29, 95% CI [0.01, 0.57], p = .041). These associations remained significant after adjusting for objective socioeconomic status. No significant associations between national SSS and cardiovascular measures were observed.

CONCLUSION

In conclusion, one's perceived social position in the social environment (i.e., local SSS) is associated with nocturnal BP dipping. Therefore, local SSS may be an important psychosocial factor linking social inequality and cardiovascular health.

Circadian rhythms of blood pressure in hypertensive patients with cerebral microbleeds

BACKGROUND

Whether the circadian rhythms of blood pressure (BP) contribute to the presence of cerebral microbleeds (CMBs) remains unknown. This study aimed to assess the relationship between nocturnal BP and CMBs in hypertensive patients.

METHODS

This prospective case-control study recruited 51 hypertensive patients with CMBs and 51 hypertensive patients without CMBs, matched with age and gender, serving as controls. A 24-h ambulatory BP monitoring was conducted in all subjects. Differences in ambulatory BP parameters between the two groups were compared. Logistic regression analyzes were conducted to investigate the relationship between the ambulatory BP parameters and presence of CMBs.

RESULTS

Patients with CMBs had a significant higher nocturnal mean SBP and lower relative nocturnal SBP dipping rate. Two logistic models were constructed to explore the association between ABPM indices and the presence of CMBs, adjusted with history of ischemic stroke and smoking. In model 1, higher nocturnal mean SBP positively correlated with presence of CMBs [standardized β = 0.254, odds ratio (OR) = 1.029, p = .041]. In model 2, the relative nocturnal SBP dipping rate was negatively correlated with CMBs (standardized β = -.363, OR = 0.918, p = .007). Only patients with deep CMBs had significant higher nocturnal mean SBP and lower relative nocturnal SBP dipping rate in comparison with those without CMBs.

CONCLUSIONS

Higher nocturnal SBP and lower relative nocturnal SBP dipping rate may be associated with CMBs in hypertensive patients.

High prevalence of non-dipping patterns among Black Africans with uncontrolled hypertension: a secondary analysis of the CREOLE trial

BACKGROUND

Dipping of blood pressure (BP) at night is a normal physiological phenomenon. However, a non-dipping pattern is associated with hypertension mediated organ damage, secondary forms of hypertension and poorer long-term outcome. Identifying a non-dipping pattern may be useful in assessing risk, aiding the decision to investigate for secondary causes, initiating treatment, assisting decisions on choice and timing of antihypertensive therapy, and intensifying salt restriction.

OBJECTIVES

To estimate the prevalence and factors associated with non-dipping pattern and determine the effect of 6 months of three antihypertensive regimens on the dipping pattern among Black African hypertensive patients.

METHODS

This was a secondary analysis of the CREOLE Study which was a randomized, single blind, three-group trial conducted in 10 sites in 6 Sub-Saharan African countries. The participants were 721 Black African patients, aged between 30 and 79 years, with uncontrolled hypertension and a baseline 24-h ambulatory blood pressure monitoring (ABPM). Dipping was calculated from the average day and average night systolic blood pressure measures.

RESULTS

The prevalence of non-dipping pattern was 78% (564 of 721). Factors that were independently associated with non-dipping were: serum sodium > 140 mmol/l (OR = 1.72, 95% CI 1.17-2.51, p-value 0.005), a higher office systolic BP (OR = 1.03, 95% CI 1.01-1.05, p-value 0.003) and a lower office diastolic BP (OR = 0.97, 95% CI 0.95-0.99, p-value 0.03). Treatment allocation did not change dipping status at 6 months (McNemar's Chi2 0.71, p-value 0.40).

CONCLUSION

There was a high prevalence of non-dipping among Black Africans with uncontrolled hypertension. ABPM should be considered more routinely in Black Africans with uncontrolled hypertension, if resources permit, to help personalise therapy. Further research is needed to understand the mechanisms and causes of non-dipping pattern and if targeting night-time BP improves clinical outcomes. Trial registration ClinicalTrials.gov (NCT02742467).

Patterns of Circadian Variation in 24-Hour Ambulatory Blood Pressure, Heart Rate, and Sympathetic Tone Correlate with Cardiovascular Disease Risk: A Cluster Analysis

To investigate whether specific time series patterns for blood pressure (BP), heart rate (HR), and sympathetic tone are associated with metabolic factors and the 10-year risk of atherosclerotic cardiovascular disease (ASCVD). A total of 989 patients who underwent simultaneous 24-hour ambulatory BP and Holter electrocardiogram monitoring were enrolled. The patients were categorized into sixteen groups according to their circadian patterns using the consensus clustering analysis method. Metabolic factors, including cholesterol profiles and apolipoprotein, were compared. The 10-year ASCVD risk was estimated based on the Framingham risk model. Overall, 16 significant associations were found between the clinical variables and cluster groups. Age was commonly associated with all clusters in systolic BP (SBP), diastolic BP (DBP), HR, and sympathetic tone. Metabolic indicators, including diabetes, body mass index, total cholesterol, high-density lipoprotein, and apolipoprotein, were associated with the four sympathetic tone clusters. In the crude analysis, the ASCVD risk increased incrementally from clusters 1 to 4 across SBP, DBP, HR, and sympathetic tone. After adjustment for multiple variables, however, only sympathetic tone clusters 3 and 4 showed a significantly high proportion of patients at high risk (≥7.5%) of 10-year ASCVD (odds ratio (OR) = 5.90, 95% confidential interval (CI) = 1.27-27.46, and P value = 0.024 and OR = 15.28, 95% CI = 3.59-65.11, and P value < 0.001, respectively). Time series patterns of BP, HR, and sympathetic tone can serve as an indicator of aging. Circadian variations in sympathetic tone can provide prognostic information about patient metabolic profiles and indicate future ASCVD risk.

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.

Blood Pressure Variability and Autonomic Dysfunction

PURPOSE OF REVIEW

This review considers the relationship between abnormal blood pressure (BP) variability and autonomic dysfunction through an attempt to answer questions about its clinical relevance and pertinence to diabetes and cardiovascular autonomic neuropathy (CAN) and which therapeutic measures can lessen its cardiovascular impact.

RECENT FINDINGS

Office, ambulatory, and home BP monitoring identify posture-related, circadian, short-term, and long-term BP variabilities. Abnormal BP variability is a risk marker for organ damage, mortality, and cardiovascular events. Moreover, BP variability changes are common in diabetes and associated with CAN and possibly exacerbated by comorbidities like nephropathy, obstructive sleep apnoea syndrome, and chronic pain. The prognostic role of nondipping and reverse dipping is well documented in diabetes. Some findings suggest the possibility of restoring dipping with the dosage time of antihypertensive agents. Diabetes is a favorable scenario for altered BP variability, which might mediate the harmful effects of CAN. Preliminary data suggest the protective effect of targeting BP variability. However, further longitudinal outcome studies are needed. In the meantime, BP variability measures and practical expedients in antihypertensive treatment should be implemented in diabetes.

Psychosocial Correlates of Nocturnal Blood Pressure Dipping in African Americans: The Jackson Heart Study

BACKGROUND

African Americans exhibit a lower degree of nocturnal blood pressure (BP) dipping compared with Whites, but the reasons for reduced BP dipping in this group are not fully understood. The aim of this study was to identify psychosocial factors associated with BP dipping in a population-based cohort of African Americans.

METHODS

This cross-sectional study included 668 Jackson Heart Study (JHS) participants with valid 24-hour ambulatory BP data and complete data on psychosocial factors of interest including stress, negative emotions, and psychosocial resources (e.g., perceived support). The association of each psychosocial factor with BP dipping percentage and nondipping status (defined as <10% BP dipping) was assessed using linear and Poisson regression models, respectively, with progressive adjustment for demographic, socioeconomic, biomedical, and behavioral factors.

RESULTS

The prevalence of nondipping was 64%. Higher depressive symptoms, higher hostility, and lower perceived social support were associated with a lower BP dipping percentage in unadjusted models and after adjustment for age, sex, body mass index, and mean 24-hour systolic BP (P < 0.05). Only perceived support was associated with BP dipping percentage in fully adjusted models. Also, after full multivariable adjustment, the prevalence ratio for nondipping BP associated with 1 SD (7.1 unit) increase in perceived support was 0.93 (95% CI: 0.88-0.99). No other psychosocial factors were associated with nondipping status.

CONCLUSIONS

Lower perceived support was associated with reduced BP dipping in this study. The role of social support as a potentially modifiable determinant of nocturnal BP dipping warrants further investigation.

Reproducibility of ambulatory blood pressure values and circadian blood pressure patterns in untreated subjects in a 1-11 month interval

OBJECTIVE

To evaluate in untreated subjects the reproducibility of mean values and four circadian patterns between two ambulatory blood pressure monitoring (ABPM) recordings separated by 1-11 months.

METHODS

We performed a retrospective analysis of 481 individuals (59% women) evaluated by ABPM on two occasions, visit 1 (V1) and 2 (V2), separated by 5.5+0.2 months. Four circadian patterns were defined by night/day systolic blood pressure (SBP) ratios: reverse dippers (RD), ratio >1.0; non-dippers (ND), ratio 0.9-1.0; dippers (D), ratio 0.8-<0.9; and extreme dippers (ED), ratio <0.8. Coefficients of correlation and concordance between the ABPM values at V1 and V2 and the reproducibility of the RD, ND, D and ED patterns were calculated by the percentage of the same profile from V1 to V2.

RESULTS

Mean 24-h blood pressure (BP) at V1 and V2 was 126.8/75.9±0.5/0.5 vs. 126.5/75.7±0.5/0.4 mmHg (NS). Nighttime SBP fall was 9.8±0.4 (V1) and 9.6±0.3% (V2) (NS). The correlation coefficient of ABPM data at V1 vs. at V2 was 0.41-0.69 (p<0.001) and the concordance coefficient was 0.34-0.57 (p<0.01). At V1, 38 subjects were classified as ED (7.9%); D, n=216 (44.9%), 187 as ND (38.9%) and 40 as RD (8.3%). At V2 only 26.3% of ED, 44.9% of D, 54.5% of ND and 40% of RD maintained the same profile as at V1.

CONCLUSION

In untreated subjects ABPM has high reproducibility for mean values but only modest reproducibility for circadian profiles, thereby challenging the prognostic value of BP dipping patterns.

Interactive influences of ethnicity, endothelin-1 gene, and everyday discrimination upon nocturnal ambulatory blood pressure

BACKGROUND

Everyday discrimination scale scores are associated with increased ambulatory blood pressure (BP) and reduced nocturnal dipping, and the endothelin-1 (ET-1)/Lys198Asn polymorphism is associated with increased resting BP and exaggerated BP reactivity among African Americans compared to European Americans. Combined influences of these factors on BP control are unknown.

PURPOSE

This study tested the hypothesis of a three-way interaction between ethnicity, ET-1 carrier status, and everyday discrimination upon ambulatory BP and nocturnal dipping.

METHODS

Baseline laboratory anthropometrics and the everyday discrimination scale were completed by 352 (175 African American) young adult normotensives, followed by 24-h ambulatory BP monitoring.

RESULTS

For nocturnal dipping, multiple regression models controlling for age, sex, ethnicity, and body mass index revealed significant three-way ET-1 × everyday discrimination × ethnicity interactions. Specifically, among African American ET-1 T-allele carriers, increases in everyday discrimination led to reduced nocturnal dipping.

CONCLUSIONS

African Americans that carry the ET-1/Lys198Asn T-allele and report higher everyday discrimination scores may be at particular risk for reduced nocturnal dipping.

A reverse dipping pattern predicts cardiovascular mortality in a clinical cohort

An abnormal dipping pattern in ambulatory blood pressure monitoring (ABPM) is a cardiovascular (CV) risk factor. However, its impact on CV mortality has not been investigated sufficiently in clinical practice to be considered a standard parameter. We assessed the association between abnormal dipping patterns and increased CV mortality in a tertiary hospital in Korea. Our retrospective cohort study included 401 patients who underwent ABPM between 1994 and 1996 in Hanyang University Hospital, Seoul, Korea. The patients were classified as risers (<0% drop in systolic BP; n=107), and others included dippers and non-dippers (≥0% drop, n=294). The follow-up period was 120 months. The frequency of CV mortality was 14.0% in risers and 5.8% in others. A Cox regression analysis found a significant association between dipping pattern and CV mortality, after adjusting for age, gender, body mass index, hypertension, diabetes mellitus, smoking and hypercholesterolemia. Risers were at greater risk of CV death than others (RR, 3.02, P=0.022), but there was no difference in event rates between dippers and non-dippers. The reverse dipping pattern may be more frequent in clinical settings than in the population at large, and it is strongly associated with increased risk of CV mortality in Korea.

Nonlinear mixed effects modeling of the diurnal blood pressure profile in a multiracial population

BACKGROUND

Cardiac and cerebrovascular events in hypertensive patients are related to specific features of the 24-hour diurnal blood pressure (BP) profile (i.e., daytime and nighttime BP, nocturnal dip (ND), and morning surge (MS)). This investigation aimed to characterize 24-hour diurnal systolic BP (SBP) with parameters that correlate directly with daytime and nighttime SBP, ND, and MS using nonlinear mixed effects modeling.

METHODS

Ambulatory 24-hour SBP measurements (ABPM) of 196 nontreated subjects from three ethnic groups were available. A population model was parameterized in NONMEM to estimate and evaluate the parameters baseline SBP (BSL), nadir (minimum SBP during the night), and change (SBP difference between day and night). Associations were tested between these parameters and patient-related factors to explain interindividual variability.

RESULTS

The diurnal SBP profile was adequately described as the sum of 2 cosine functions. The following typical values (interindividual variability) were found: BSL = 139 mm Hg (11%); nadir = 122 mm Hg (14%); change = 25 mm Hg (52%), and residual error = 12 mm Hg. The model parameters correlate well with daytime and nighttime SBP, ND, and MS (R (2) = 0.50-0.92). During covariate analysis, ethnicity was found to be associated with change; change was 40% higher in white Dutch subjects and 26.8% higher in South Asians than in blacks.

CONCLUSIONS

The developed population model allows simultaneous estimation of BSL, nadir, and change for all individuals in the investigated population, regardless of individual number of SBP measurements. Ethnicity was associated with change. The model provides a tool to evaluate and optimize the sampling frequency for 24-hour ABPM.

Glucose abnormalities associated with impaired nocturnal fall in blood pressure in normotensive severely obese patients

BACKGROUND

The purpose of this study was to identify factors affecting the nocturnal decline in blood pressure (BP) in severe obesity.

METHODS

Clinical, biochemical, polysomnographic data, glucose tolerance status, and body fat composition were obtained in 82 candidates for bariatric surgery (mean age: 40 (11) years; BMI: 46 (4)kg/m(2)). To determine the nocturnal BP fall we used 24-h ambulatory BP monitoring to measure the magnitude (Δ) of nocturnal decline, the % day-night systolic BP (SBP) and diastolic BP (DBP), dipper status and nocturnal hypertension (HT).

RESULTS

Twenty-three percent of patients had nocturnal HT. Sixty percent had non dipper status, of which 95% had nocturnal HT. No specific factors were associated with the average 24-h SBP and DBP. Having glucose abnormalities was of primary importance for all variables evaluating nocturnal BP decline independent of daytime BP levels and severity of obesity. In comparing patients with or without glucose tolerance abnormalities, the night-time SBP and DBP were significantly higher and the Δ nocturnal decline and % day-night in both SBP and DBP were significantly lower in those with glucose tolerance abnormalities. In an adjusted multivariate model, having both glucose abnormalities and nocturnal HT remained associated with non dipper status with an OR of 3.13 (95% CI 1.11-8.87, p=0.03) and 14.93 (95% CI 1.77-125.62, p=0.001), respectively.

CONCLUSION

In normotensive severely obese patients, non dipper status and nocturnal HT are common, and the presence of glucose abnormalities was the primary variable associated with impaired nocturnal fall in BP.

Changes in haemostatic and platelet activation markers in non-dipper hypertensive patients

BACKGROUND

Non-dipper hypertensive patients are at increased risk for cardiovascular disease. Coagulation and fibrinolysis activation factors are considered as risk factors for cardiovascular disease. The aim of this study was to examine the relationship between the haemostatic and platelet activation markers and the non-dipping pattern in treated hypertensive patients.

PATIENTS AND METHODS

Seventy-one treated hypertensive patients (53 with essential and 18 with secondary hypertension, due to chronic kidney disease-stage 4), aged 33 to 81 years (30 men), were classified as dippers and non-dippers, according to the presence or absence, respectively, of a decline of nocturnal average systolic blood pressure (BP) by more than 10% of the diurnal BP (non-dipping pattern) on 24-hour ambulatory BP monitoring. Plasma levels of factors VIII and IX, fibrinogen, prothrombin fragment 1 + 2, thrombin-antithrombin complex, protein C, plasmin-alpha-2 antiplasmin complex, D-dimer and platelet factor 4 were measured in all patients.

RESULTS

Thirty-seven patients were classified as dippers and 34 as non-dippers. The percentages of patients with essential and with secondary hypertension were similar in the dippers and in the non-dippers groups (both P = 0.754). Multivariate analysis of variance showed statistically significant differences in all measured variables between dippers and non-dippers (P = 0.043). Plasma levels of factors VIII and IX, fibrinogen, prothrombin fragment 1 + 2, protein C, plasmin-alpha-2-antiplasmin complex, and D-dimers were significantly higher in non-dippers when compared to dippers (P < 0.05 for all). In contrast, there were no significant differences in plasma levels of thrombin-antithrombin complex (P = 0.955) and platelet factor 4 (P = 0.431) between the two groups.

CONCLUSION

This study provides evidence that non-dipper treated hypertensive patients exhibit alterations in haemostasis, which may affect their cardiovascular risk.

The effect of zolpidem on sleep quality, stress status, and nondipping hypertension

OBJECTIVE

Poor sleep quality and stress status have previously been shown to be closely associated with higher activation of the sympathetic nervous system and to be independent predictors of nondipping hypertension. This study aimed to evaluate the effects of the non-hypotensive sedative zolpidem on sleep quality, stress status, and nondipping hypertension.

METHODS

A total of 103 nondippers were defined as poor or good sleepers by the Pittsburgh Sleep Quality Index. They were randomized to receive zolpidem or placebo treatment for 30 days. Stress status was assessed by the Perceived Stress Scale, and levels of epinephrine and norepinephrine were examined to investigate the underlying mechanisms.

RESULTS

Poor sleepers treated with zolpidem for 30 days showed significant improvements in sleep quality and stress levels (P<0.01). More nondippers were converted to dippers in the group of poor sleepers treated with zolpidem (11 of 22 patients, 50.0%) than in the placebo (2 of 23, 8.7%) (P<0.01). Epinephrine and norepinephrine levels were significantly reduced in poor sleepers treated with zolpidem (P<0.05).

CONCLUSION

The results of this study suggest that zolpidem can improve sleep quality and stress status, and can convert nondippers with poor sleep quality into dippers. It may be an option for treating nondipping hypertensive patients with poor sleep quality.

Short-term reproducibility of ambulatory blood pressure monitoring in autosomal dominant polycystic kidney disease

BACKGROUND AND OBJECTIVES

Nondipping, defined as a less than 10% decline in Night:Day (N:D) ratio of blood pressure using 24 h ambulatory blood pressure monitoring, is associated with poor cardiovascular outcomes. However, its reproducibility has been questioned in autosomal dominant polycystic kidney disease.

MATERIALS AND METHODS

Twenty-five of 29 recruited hypertensive or prehypertensive patients with autosomal dominant polycystic kidney disease completed ambulatory blood pressure monitoring on two occasions, 7-15 days apart, on a stable antihypertensive regimen. Daytime and night-time were defined as 6:00-21:59 h and 22:00-5:59 h, respectively. Correlation and concordance coefficients for systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate were determined based on N:D and Asleep:Awake (A:A) ratios. Consistency of dipping was assessed by using Cohen's Kappa statistics.

RESULTS

Mean (±standard deviation) for age, estimated glomerular filtration rate, differences in daytime and night-time SBP and DBP were 43.12 years (8.55 years), 63.1 ml/min (20.5 ml/min), 11.74 mmHg (8.2 mmHg), and 10.82 mmHg (6.4 mmHg), respectively. Seventeen of 25 (68%) and 18 of 25 (72%) participants maintained the same dipping category based on D:N or A:A separation. Cohen's Kappa was 0.34 for D:N ratio and 0.38 for A:A ratio. Correlation and concordance coefficients were 0.89 and 0.88 for daytime SBP, 0.91 and 0.91 for daytime DBP, 0.79 and 0.78 for night-time SBP, 0.81 and 0.80 for night-time DBP, 0.58 and 0.56 for N:D ratio of SBP, and 0.56 and 0.53 for N:D ratio of DBP. Coefficients for A:A ratio were almost identical to N:D values except for A:A ratios of SBP (0.69 and 0.67) and DBP (0.48 and 0.45).

CONCLUSION

Repeated measures of SBP and DBP, 7-15 days apart, are highly correlative and concordant in the studied population, but nondipping, even though predominant, was found to be modestly reproducible.

Non-Dipper Pattern is a Determinant of the Inappropriateness of Left Ventricular Mass in Essential Hypertensive Patients

Background and Objectives

Inappropriately high left ventricular mass (iLVM) is known to be related to cardiovascular prognosis. A non-dipper pattern has a greater mean left ventricular (LV) mass than the dipper pattern in hypertensive patients. However, the appropriateness of LV mass in dipper or non-dipper patterns has not been adequately investigated. The aim of this study was to define the relationship between nocturnal dipping and the appropriateness of LV mass.

Subjects and Methods

Using the ambulatory blood pressure monitoring (ABPM) database, the data of 361 patients who underwent ABPM and echocardiography was analyzed retrospectively. Appropriateness of LV mass was calculated as observed/predicted ratio of LV mass (OPR) using a Korean-specified equation. Nocturnal dipping was expressed as percent fall in systolic blood pressure (BP) during the night compared to the day.

Results

Daytime, nighttime and 24 hours BP in hypertensive patients was 140.4±14.8 mmHg, 143.7±15.2 mmHg and 129.4±20.0 mmHg, respectively. OPR was 106.3±19.9% and nocturnal dipping was 10.2±10.9 mmHg. In a multiple linear regression model, 24 hours systolic BP (β=0.097, p=0.043) and nocturnal dipping (β=-0.098, p=0.046) were independent determinants of OPR as well as age (β=0.130, p=0.025) and body mass index (BMI) (β=0.363, p<0.001). Odds ratio of the non-dipper pattern was 2.134 for iLVM (p=0.021) and 3.694 for obesity (p<0.001; BMI >25 kg/m²).

Conclusion

The non-dipper pattern is independently associated with iLVM in hypertensive patients as well as obesity.

Efficacy of an olmesartan medoxomil-based treatment algorithm in patients with hypertension and type 2 diabetes: analysis of diurnal blood pressure control as assessed by 24-hour ambulatory blood pressure monitoring

Objective: Secondary, prespecified analysis of a single-arm, open-label study evaluating the efficacy of olmesartan medoxomil (OM) plus hydrochlorothiazide (HCTZ) in patients with hypertension and type 2 diabetes.

Methods: After placebo run-in, 192 patients received OM 20 mg/day for 3 weeks. If blood pressure (BP) remained ≥120/70 mmHg, patients were uptitrated every 3 weeks to OM 40 mg/day, OM/HCTZ 40/12.5 mg/day, and OM/HCTZ 40/25 mg/day. Efficacy was evaluated by 24-hour ambulatory BP monitoring. Secondary endpoints included changes in ambulatory systolic BP (SBP) and diastolic BP (DBP) during daytime (08:00 to 16:00) and nighttime (22:00 to 06:00), as well as achievement of prespecified ambulatory BP targets in the total cohort and subgroups based on gender, race, hypertension severity, and age (≥65 or <65 years). Dipper status (nocturnal decrease in BP ≥10% of mean daytime BP) was assessed.

Results: At baseline, mean ambulatory BP was 151.2 ± 12.7/87.6 ± 9.0 mmHg during the daytime and 140.3 ± 13.1/78.1 ± 8.6 mmHg during the nighttime. Mean daytime and nighttime ambulatory BP was reduced from baseline by 22.3 ± 13.7/12.0 ± 8.9 mmHg and 18.8 ± 12.4/ 10.2 ± 7.2 mmHg, respectively. The reduction in daytime ambulatory SBP was 24.4 ± 11.8 mmHg in Blacks, 21.7 ± 14.2 mmHg in non-Blacks, 23.6 ± 12.3 mmHg in females, 21.2 ± 14.8 mmHg in males, 23.4 ± 11.6 mmHg in patients aged ≥65 years, and 21.9 ± 14.4 mmHg in those aged <65 years. Ambulatory BP targets of <130/80, <125/75, and <120/80 mmHg were reached by 51.7%, 36.0%, and 32.6% of patients during the daytime and 69.8%, 60.5%, and 50.6% of patients during the nighttime. After 12 weeks of treatment, 36.4% of baseline nondippers converted to dippers.

Conclusions: OM ± HCTZ effectively lowered ambulatory BP in patients with type 2 diabetes and hypertension, enabling them to achieve ambulatory BP targets during both the daytime and nighttime.

From pioneering to implementing automated blood pressure measurement in clinical practice: Thomas Pickering's legacy

Thomas G. Pickering spent most of his scientific career in carrying out research on clinical hypertension and blood pressure (BP) measurement. In our review of Pickering's seminal work, we first focused on white-coat hypertension and masked hypertension, two terms that he had introduced. Next, we highlighted the early publications of Pickering on diurnal BP variability and on the clinical application of self-measured BP. Pickering's work inspired many investigators worldwide and constituted a solid basis for further research. Pickering's original ideas led to algorithms for risk stratification involving white-coat hypertension and masked hypertension, diurnal BP variability, and self-measured BP. Recent studies validated Pickering's observations in terms of cardiovascular outcome and bridged the path from concept to application in clinical practice.

The reproducibility of ethnic differences in the proportional awake-sleep blood pressure decline among women

A growing body of evidence indicates that African Americans (AA), on average, have a smaller proportional decline in blood pressure (BP) from waking to sleep than European Americans (EA), but this difference is largely based on correlational data from a single assessment day. The persistence of this difference over repeated sampling is not well established. The purpose of this study was to evaluate whether ethnic differences in the awake-sleep BP decline between AA and EA persisted over three monthly assessments. The subjects were 47 AA (age = 39.7 +/- 8.7) and 92 EA (age = 37.4 +/- 9.2) normotensive women. Subjects had 24-h ambulatory BP monitoring done on midweek workdays at 1-month intervals for three consecutive months. The proportional decline in BP was calculated as follows: (average awake - average sleep)/average sleep. The persistence of ethnic differences was evaluated using repeated-measures ANCOVA and by examining Bland-Altman plots. The ANCOVA results revealed that overall, the proportional decline of AA women was less than that of EA women for both SBP (P < 0.038) and DBP (P < 0.083), consistent with previous research, and that there were also no significant ethnic differences by monthly assessment. Bland-Altman plots revealed that overall and by ethnicity, the proportional decline in BP among individual subjects over the 3 months was also reproducible. These results suggest that the ethnic difference in awake-sleep BP between AA and EA women persists over time and that the awake-sleep decline in BP among individuals, whether AA or EA, is also reproducible.

Low life purpose and high hostility are related to an attenuated decline in nocturnal blood pressure

OBJECTIVE

An attenuation of the nighttime decline in blood pressure (BP) predicts cardiovascular disease and cardiovascular-related mortality, beyond daytime BP levels. We investigated whether positive and negative psychological attributes were associated with sleep-wake BP ratios and examined sleep parameters as potential mediators of these relationships.

DESIGN

Two hundred twenty-four participants (50% men; 43% Black; mean age = 60 years) underwent ambulatory BP monitoring for 2 days and nights. Self-reports of positive and negative psychological attributes were collected. In-home polysomnography was conducted for 2 nights, and a wrist actigraph was worn for 9 nights.

MAIN OUTCOME MEASURES

Sleep-wake mean arterial pressure (MAP) ratios.

RESULTS

After adjustment for demographics, body mass index, and hypertensive status, low life purpose and high hostility were associated with high sleep-wake MAP ratios. Depression, anxiety, and optimism were not related to MAP ratios. Sleep latency, fragmentation, architecture, and the apnea-hypopnea index were examined as potential mediators between psychological attributes and MAP ratios; only long sleep latency mediated the relationship between hostility and MAP ratios.

CONCLUSION

Low life purpose and high hostility are associated with high sleep-wake BP ratios in Black and White adults, and these relationships are largely independent of sleep.

Everyday discrimination and nocturnal blood pressure dipping in black and white americans

OBJECTIVE

To investigate whether an association exists between experiences of everyday discrimination and blood pressure (BP) dipping in a biracial sample of black and white adults. Attenuated nocturnal BP dipping is closely linked to cardiovascular morbidity and mortality. Self-reported experiences of everyday discrimination have also been associated with negative cardiovascular health outcomes.

METHODS

Seventy-eight hypertensive and normotensive women and men (n = 30 black and 48 white) reported on their experiences of everyday discrimination (Everyday Discrimination Scale) and underwent two separate 24-hour ambulatory BP monitoring (ABPM) sessions approximately 1 week apart.

RESULTS

Correlation analysis revealed that higher endorsement of everyday discrimination was significantly associated with less diastolic BP (DBP) and systolic BP (SBP) dipping (p < .05). Subsequent hierarchical regression analyses indicated that everyday discrimination explained 8% to 11% of the variance in SBP and DBP dipping above and beyond other demographic and life-style-related factors, including race, age, 24-hour BP, body mass index, and current socioeconomic status. The relationship between discrimination and dipping was significantly stronger on the second night of monitoring. Finally, analyses revealed that everyday discrimination mediated the relationship between race and BP dipping.

CONCLUSIONS

These findings suggest that experiences of everyday discrimination are associated with less nocturnal SBP and DBP dipping above and beyond the effect of known covariates. The use of multiple ABPM sessions may facilitate the detection of relationships between psychological variables and BP dipping.

Brain microbleeds relate to higher ambulatory blood pressure levels in first-ever lacunar stroke patients

BACKGROUND AND PURPOSE

Hypertension is an important risk factor for brain microbleeds (BMBs) in lacunar stroke patients. However, beyond the qualitative label "hypertension," little is known about the association with ambulatory blood pressure (BP) levels.

METHODS

In 123 first-ever lacunar stroke patients we performed 24-hour ambulatory BP monitoring after the acute stroke-phase. We counted BMBs on T2*-weighted gradient-echo MR images. Because a different etiology for BMBs according to location has been suggested, we distinguished between BMBs in deep and lobar location.

RESULTS

BMBs were seen in 36 (29.3%) patients. After adjusting for age, sex, number of antihypertensive drugs, asymptomatic lacunar infarcts, and white matter lesions, we found 24-hour, day, and night systolic and diastolic BP levels to be significantly associated with the presence and number of BMBs (odds ratios 1.6 to 2.3 per standard deviation increase in BP). Distinguishing between different locations, various BP characteristics were significantly associated with the presence of deep (or combined deep and lobar) BMBs, but not with purely lobar BMBs.

CONCLUSIONS

Our results underline the role of a high 24-hour BP load as an important risk factor for BMBs. The association of BP levels with deep but not purely lobar BMBs is in line with the idea that different vasculopathies might be involved. Deep BMBs may be a particular marker of BP-related small vessel disease, but longitudinal and larger studies are now warranted to substantiate these findings.

Socioeconomic and psychosocial factors mediate race differences in nocturnal blood pressure dipping

BACKGROUND

Reduced nocturnal blood pressure (BP) dipping is more prevalent among blacks living in the United States than whites and is associated with increased target organ damage and cardiovascular risk. The primary aim of this study was to determine whether socioeconomic and psychosocial factors help to explain racial differences in dipping. In order to address the limited reproducibility of dipping measures, we investigated this question in a sample of participants who underwent multiple ambulatory BP monitoring (ABPM) sessions.

METHODS

The study sample included 171 black and white normotensive and mildly hypertensive participants who underwent three ABPM sessions, each 1 month apart, and completed a battery of questionnaires to assess socioeconomic and psychosocial factors.

RESULTS

As expected, blacks showed less dipping than whites, after adjusting for age, sex, body mass index (BMI), and mean 24-h BP level (mean difference = 3.3%, P = 0.002). Dipping was related to several of the socioeconomic and psychosocial factors examined, with higher education and income, being married, and higher perceived social support, each associated with a larger dipping percentage. Of these, marital status and education were independently associated with dipping and together accounted for 36% of the effect of race on dipping.

CONCLUSIONS

We identified a number of socioeconomic and psychosocial correlates of BP dipping and found that reduced dipping among blacks vs. whites is partially explained by marital status (being unmarried) and lower education among blacks. We also present results suggesting that repeated ABPM may facilitate the detection of associations between dipping and other variables.

Prevalence and factors associated with circadian blood pressure patterns in hypertensive patients

Ambulatory blood pressure (BP) monitoring has become useful in the diagnosis and management of hypertensive individuals. In addition to 24-hour values, the circadian variation of BP adds prognostic significance in predicting cardiovascular outcome. However, the magnitude of circadian BP patterns in large studies has hardly been noticed. Our aims were to determine the prevalence of circadian BP patterns and to assess clinical conditions associated with the nondipping status in groups of both treated and untreated hypertensive subjects, studied separately. Clinical data and 24-hour ambulatory BP monitoring were obtained from 42,947 hypertensive patients included in the Spanish Society of Hypertension Ambulatory Blood Pressure Monitoring Registry. They were 8384 previously untreated and 34,563 treated hypertensives. Twenty-four-hour ambulatory BP monitoring was performed with an oscillometric device (SpaceLabs 90207). A nondipping pattern was defined when nocturnal systolic BP dip was <10% of daytime systolic BP. The prevalence of nondipping was 41% in the untreated group and 53% in treated patients. In both groups, advanced age, obesity, diabetes mellitus, and overt cardiovascular or renal disease were associated with a blunted nocturnal BP decline (P<0.001). In treated patients, nondipping was associated with the use of a higher number of antihypertensive drugs but not with the time of the day at which antihypertensive drugs were administered. In conclusion, a blunted nocturnal BP dip (the nondipping pattern) is common in hypertensive patients. A clinical pattern of high cardiovascular risk is associated with nondipping, suggesting that the blunted nocturnal BP dip may be merely a marker of high cardiovascular risk.

Prognostic value of nocturnal blood pressure and reverse-dipping status on the occurrence of cardiovascular events in hypertensive diabetic patients

AIM

To assess whether reverse-dipping status is associated with cardiovascular (CV) events such as CV death, myocardial infarction (MI) or stroke in diabetic patients with hypertension.

METHODS

A total of 97 diabetic patients underwent their first ambulatory blood pressure monitoring (ABPM 1). "Reverse dippers" were defined as patients with a nighttime systolic and/or diastolic blood pressure (BP) greater than daytime systolic and/or diastolic BP. Other patients were called "others". A second ABPM (ABPM 2) was done after a median delay of 2.6 years. Patients were then followed for a further 2.9-year median period (total median follow-up: 5.5 years).

RESULTS

After ABPM 1, CV events occurred in 53% of the reverse dippers (n=15) and in 29% of the others (n=82). Kaplan-Meier curves showed significant differences between the two groups (P=0.003). Mean nighttime systolic BP on ABPM 1 was 148+/-23 mmHg and 142+/-19 mmHg in patients who did and did not experience a CV event, respectively. With Cox analysis adjusted for confounders, a 10 mmHg increase in nighttime systolic BP was associated with a 35% increase in the risk of a CV event (hazard ratio [HR]: 1.35, P=0.003). The HR for a CV event in reverse- versus nonreverse-dipping status was 2.79 (P=0.023). After ABPM 2, the relationship between the reverse-dipping status and occurrence of CV events was no longer evident (P=0.678). Nighttime systolic BP remained predictive of CV events (P=0.001).

CONCLUSION

These findings suggest that nighttime systolic BP per se appeared to be a stronger predictor of an excess risk of CV events compared with reverse-dipping status.