Isolated Nocturnal Hypertension: What Do We Know and What Can We Do?

Circulating angiotensin-(1-7) is decreased in patients with isolated nocturnal hypertension

Isolated nocturnal hypertension (INHT), defined as nighttime elevated blood pressure (BP) with normal daytime BP assessed by ambulatory BP monitoring, is associated with higher cardiovascular morbidity and mortality. We hypothesized that an alteration in the circulating renin-angiotensin system (RAS) contributes to INHT development. We examined circulating levels of angiotensin (Ang) (1-7) and Ang II and ACE2 activity in 26 patients that met the INHT criteria, out of 50 that were referred for BP evaluation (62% women, 45 ± 16 years old). Those with INHT were older, had a higher BMI, lower circulating Ang-(1-7) (P = 0.002) and Ang II levels (P = 0.02) and no change in ACE2 activity compared to those normotensives. Nighttime DBP was significantly correlated with Ang-(1-7) and Ang II levels. Logistic regression showed significant association in Ang-(1-7) and Ang II levels with INHT. Our study reveals differences in circulating RAS in individuals with INHT.

Isolated Nocturnal Hypertension in People Living With Human Immunodeficiency Virus: A Cross-Sectional Study

BACKGROUND

Nocturnal hypertension (NH) is a potent cardiovascular risk factor described frequently in people with HIV (PWH). Isolated NH (INH) is less well reported in PWH because of the need for ambulatory blood pressure monitoring (ABPM) in office normotensive patients. We aim to document the prevalence of NH and INH and the clinical factors associated with these phenotypes.

METHODS

Cross-sectional study from an HIV program in Argentina. Office and ABPM measurements, as well as clinical and laboratory exploration, were performed. We defined INH as NH with daytime normotension in patients with office normotension.

RESULTS

We obtained ABPM in 66 PWH, 60% male, aged 44.7 (IQR 27-69) years; 87% receiving antiretroviral therapy, and 86.2% virologically suppressed. ABPM-based hypertension prevalence was 54.7% (95% CI: 42.5-66.3). The prevalence of NH was 48.5% (32/66), while the INH prevalence was 19.7% (95% CI: 11.7-30.9). No differences were found regarding sex, HIV viral load, CD4+ T lymphocytes count, or years of infection between normotensive and INH patients. Multiple linear regression model adjusted for sex and age determined that body mass index (β = 0.93, P < 0.01), plasma uric acid (β = 0.25, P = 0.04), plasma potassium (β = -10.1, P = 0.01), and high-sensitivity C-reactive protein (hs-CRP) (β = 0.78, P = 0.02) independently predicted nocturnal systolic blood pressure (BP) in PWH. In a multiple logistic regression model adjusted for age and sex, the presence of sedentariness, plasma potassium <4 mEq/L, BMI, and hs-CRP levels were predictors of INH.

CONCLUSION

INH is highly prevalent in PWH. Metabolic and inflammatory markers predict nocturnal SBP in PWH.

The effects of Olmesartan/amlodipine administered in the Morning or At Night on nocturnal blood pressure reduction in Chinese patients with mild-moderate essential hypertension (OMAN Trial): study protocol for a prospective, multicenter, randomized, open-label clinical trial {1}

INTRODUCTION

Hypertension increases the risk of cardiovascular disease. Uncontrolled nocturnal blood pressure is prevalent in patients taking antihypertensive medication, with an incidence rate of 30-60%. Although chronotherapy with antihypertensive agents may provide a new direction for effective control of nocturnal blood pressure, the clinical evidence base remains controversial. This research is presently underway to compare the effects of morning and bedtime administration of antihypertensive medication on nocturnal reduction and circadian rhythm of blood pressure in patients with hypertension.

METHODS AND ANALYSIS

This study is being performed as a randomized, multicenter, open-label, parallel-group, clinical trial in which 720 participants are to undergo 24-h ambulatory blood pressure measurement (ABPM) and office blood pressure measurement (OBPM) at baseline before being randomly assigned to a morning (6-10 am) or a bedtime (6-10 pm) administration group. Each participant receives one 20/5-mg tablet of olmesartan/amlodipine (OA) daily for 4 weeks and is then followed up at 4-week intervals for a total of 12 weeks. During follow-up, the OA dosage is adjusted according to the ABPM and OBPM results. Patients with uncontrolled hypertension at the first follow-up visit will receive an increase in OA dosage to 1.5 tablets/day. For patients with blood pressure that is still uncontrolled after a further 4 weeks, the dosage of OA can be increased to 2 tablets/day. The primary objective is the reduction in mean nocturnal systolic blood pressure between baseline and week 12. The secondary objectives are the reduction in ambulatory blood pressure at weeks 4 and 12 and the blood pressure control rate at weeks 4, 8, and 12.

DISCUSSION

Antihypertensive chronotherapy remains controversial. A superiority test hypothesis design has been adopted for this trial, in which all participants will be taking the same antihypertensive medication. We anticipate that our findings will determine if nocturnal blood pressure control in Chinese patients with essential hypertension varies according to whether antihypertensive medication is taken in the morning or at bedtime. This study may provide scientific evidence for the application of chronotherapy in clinical practice.

TRIAL REGISTRATION

ChiCTR2200059719. Registered on 10 May 2022 ( http://www.chictr.org.cn/edit.aspx?pid=169782&htm=4 ) {2a,2b}.

Effect of Cuff Inflation on Blood Pressure, Arousals, Sleep Efficiency, and Desaturations: Sub-Analysis of the VAST Pilot Study

The influence of cuff inflations on night-time measurements during 24 h ambulatory blood pressure (BP) measurements is unknown. We investigated the potential effect of cuff inflations on sleep parameters using measurements taken simultaneously with a cuffless device using pulse-transit-time (PTT). On the first day of measurement, standard cuff-based 24 h BP and cuffless measurements were simultaneously performed on the right and left arms (CUFF/PTT-D). In this experiment, 1-2 days after the first measurement, the cuffless device was worn alone (PTT-D). Only data from the cuffless device were analyzed. The following mean sleep parameters were analyzed: mean systolic and diastolic BP, arousals, sleep efficiency, total arousals, arousal per hour, and desaturations. In total, 21 individuals were prospectively enrolled. The mean (SD) age was 47 (±15) years, and 57% were female. The mean systolic asleep BP during CUFF/PTT-D and during PTT-D were 131 (±21) and 131 (±26) mmHg, respectively. The mean diastolic asleep BP values during CUFF/PTT-D and during PTT-D were 80 (±14) and 84 (±14) mmHg, respectively (p = 0.860, p = 0.100, respectively). Systolic and diastolic asleep mean difference was 0.1 (±18.0) and -3.6 (±9.8) mmHg, respectively. There were significantly more total arousals during PTT-D (p = 0.042). There were no significant differences seen in sleep efficiency (p = 0.339) or desaturations (p = 0.896) between the two measurement periods. We could not show any significant impact from cuff inflations during sleep, as documented by PTT-D measurements.

Prevalence and Characteristics of Isolated Nocturnal Hypertension and Masked Nocturnal Hypertension in a Tertiary Hospital in the City of Buenos Aires

Isolated nocturnal hypertension (INH) and masked nocturnal hypertension (MNH) increase cardiovascular risk. Their prevalence and characteristics are not clearly established and seem to differ among populations. We aimed to determine the prevalence and associated characteristics of INH and MNH in a tertiary hospital in the city of Buenos Aires. We included 958 hypertensive patients ≥ 18 years who underwent an ambulatory blood pressure monitoring (ABPM) between October and November 2022, as prescribed by their treating physician to diagnose or to assess hypertension control. INH was defined as nighttime BP ≥ 120 mmHg systolic or ≥70 diastolic in the presence of normal daytime BP (<135/85 mmHg regardless of office BP; MNH was defined as the presence of INH with office BP < 140/90 mmHg). Variables associated with INH and MNH were analyzed. The prevalences of INH and MNH were 15.7% (95% CI 13.5-18.2%) and 9.7 (95% CI 7.9-11.8%), respectively. Age, male sex, and ambulatory heart rate were positively associated with INH, whereas office BP, total cholesterol, and smoking habits showed a negative association. In turn, diabetes and nighttime heart rate were positively associated with MNH. In conclusion, INH and MNH are frequent entities, and determination of clinical characteristics such as those detected in this study is critical since this might contribute to a more appropriate use of resources.

Ambulatory Blood Pressure Monitoring in Pediatrics, an Update on Interpretation and Classification of Hypertension Phenotypes

PURPOSE OF REVIEW

This review highlights the major changes reflected in the 2022 American Heart Association (AHA) Scientific Statement on Ambulatory Blood Pressure Monitoring (ABPM) in Children and Adolescents with a specific focus on the newly defined phenotypes of hypertension and their epidemiology and associated outcomes.

RECENT FINDINGS

The 2022 AHA guidelines' most notable changes include the following: (1) alignment of blood pressure (BP) thresholds with the 2017 American Academy of Pediatrics (AAP) clinical practice guidelines, 2017 American College of Cardiology (ACC)/AHA hypertension guidelines, and 2016 European Society of Hypertension (ESH) pediatric recommendations; (2) expansion of the use of ABPM to diagnose and phenotype pediatric hypertension in all pediatric patients; (3) removal of BP loads from diagnostic criteria; and (4) simplified classification of new hypertension phenotypes to prognosticate risks and guide clinical management. Recent studies suggest that utilizing the 2022 AHA pediatric ABPM guidelines will increase the prevalence of pediatric ambulatory hypertension, especially for wake ambulatory hypertension in older, taller males and for nocturnal hypertension in both males and females ≥ 8 years of age. The new definitions simplify the ambulatory hypertension criteria to include only the elements most predictive of future health outcomes, increase the sensitivity of BP thresholds in alignment with recent data and other guidelines, and thus make hypertension diagnoses more clinically meaningful. This guideline will also aid in the transition of adolescents and young adults to adult medical care. Further studies will be necessary to study ambulatory BP norms in a more diverse pediatric population and evaluate the impact of these guidelines on prevalence and future outcomes.

Bedtime dosing of antihypertensive medications: systematic review and consensus statement: International Society of Hypertension position paper endorsed by World Hypertension League and European Society of Hypertension

Antihypertensive drug therapy is one of the most efficient medical interventions for preventing disability and death globally. Most of the evidence supporting its benefits has been derived from outcome trials with morning dosing of medications. Accumulating evidence suggests an adverse prognosis associated with night-time hypertension, nondipping blood pressure (BP) profile and morning BP surge, with increased incidence of cardiovascular events during the first few morning hours. These observations provide justification for complete 24-h BP control as being the primary goal of antihypertensive treatment. Bedtime administration of antihypertensive drugs has also been proposed as a potentially more effective treatment strategy than morning administration. This Position Paper by the International Society of Hypertension reviewed the published evidence on the clinical relevance of the diurnal variation in BP and the timing of antihypertensive drug treatment, aiming to provide consensus recommendations for clinical practice. Eight published outcome hypertension studies involved bedtime dosing of antihypertensive drugs, and all had major methodological and/or other flaws and a high risk of bias in testing the impact of bedtime compared to morning treatment. Three ongoing, well designed, prospective, randomized controlled outcome trials are expected to provide high-quality data on the efficacy and safety of evening or bedtime versus morning drug dosing. Until that information is available, preferred use of bedtime drug dosing of antihypertensive drugs should not be routinely recommended in clinical practice. Complete 24-h control of BP should be targeted using readily available, long-acting antihypertensive medications as monotherapy or combinations administered in a single morning dose.

Isolated nocturnal hypertension in pediatric kidney transplant recipients

BACKGROUND

Isolated nocturnal hypertension (INH) is defined as nighttime hypertension in the setting of normal daytime blood pressure (BP), diagnosed by ambulatory BP monitoring (ABPM).

METHODS AND RESULTS

Hypertension affects 60%-80% of pediatric kidney transplant recipients, and INH is the most common type of ambulatory hypertension. INH is associated with an increased prevalence of hypertension-mediated target organ damage such as left ventricular hypertrophy in adults and in pediatric kidney transplant recipients.

CONCLUSION

Ambulatory BP monitoring should be performed annually in all pediatric kidney transplant recipients to diagnose hypertension phenotypes that are not detectable by office BP such as masked hypertension, white-coat hypertension, or INH. Isolated nocturnal hypertension in pediatric transplant patients requires study as a treatment target.

Isolated Nocturnal Hypertension in Children

Isolated nocturnal hypertension (INH) is attracting attention because it has been shown to correlate with target organ damage as well as cardiovascular events in adults. INH has also been reported in children especially in those with underlying diseases including chronic kidney disease and some studies reported association with markers of early target organ damage. INH occupies the majority of nocturnal hypertension. On the other hand, masked hypertension is largely attributed to INH. INH is usually diagnosed by ambulatory blood pressure monitoring. Recently, it became possible to monitor sleep blood pressure by an automated home blood pressure device feasible also in children. The epidemiology, methodology and reproducibility, pathophysiology, relation to target organ damage, and treatment of INH in children will be reviewed here along with adult data.

Clinical risk factors and predictive score for the non-dipper profile in hypertensive patients: a case-control study

Background

Night-time BP, especially non-dipper, is a stronger predictor of adverse cardiovascular outcomes. Ambulatory blood pressure monitoring (ABPM) is a gold standard for the detection of non-dippers but it often is unavailable and expensive. This study aims to determine clinical risk factors that predict non-dipper.

Methods

An exploratory traditional case-control study, exclusive sampling of control was conducted from January 2013 to September 2018 to explore clinical risk factors associated with non-dippers in hypertensive patients. Subgroup analysis was performed in each treated and untreated hypertensive patient. The parsimonious predictive score for non-dippers was constructed.

Results

The study included 208 hypertensive patients receiving 24 h ABPM. There were 104 dippers and 104 non-dippers. Significant clinical risk factors associated with non-dippers were the age of > 65 years, average office diastolic blood pressure (DBP), and fasting plasma glucose of > 5.6 mmol/L. Results of subgroup analysis showed that dyslipidemia, history of coronary artery disease, use of angiotensin-converting enzyme inhibitors (ACEIs) and direct vasodilators, average office DBP, and serum uric acid were associated with non-dippers in treated hypertensive patients, however, there were no risk factors associated with non-dippers in the untreated group. The predictive score for non-dippers in treated group included average office DBP, dyslipidemia, serum uric acid, male, calcium channel blockers and ACEIs use. The area under Receiver Operating Characteristic (AuROC) was 0.723. A cut-off point which was > 0.0701 and prevalence of non-dippers of 46%, this score had a sensitivity of 77.4%, specificity of 65.6%, positive predictive value (PPV) of 66.1%, and negative predictive value (NPV) of 79.6%. For untreated group, age, hemoglobin and body mass index were included in the predictive model. AuROC was 0.74. There was a sensitivity of 51.9%, specificity of 91.2%, PPV of 82.4%, and NPV of 70.5% at the cut-off point of > 0.357, and prevalence of 44%.

Conclusion

There were several significant clinical risk factors associated with non-dippers in treated hypertensive patients. The predictive score might be useful for the detection of non-dippers; however, it cannot replace ABPM.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40885-021-00180-4.

Whole blood viscosity predicts nondipping circadian pattern in essential hypertension

Aim: We aimed to investigate the association between whole blood viscosity (WBV) and nondipping pattern in patients with essential hypertension. Materials & methods: A total of consecutive 530 patients who had been evaluated by ambulatory blood pressure monitoring were included. WBV was estimated by using hematocrit and plasma total protein levels for both WBV in low shear rate (0.5 s-1) and WBV in high shear rate (208 s-1) according to the de Simone's formula. Results: In the multivariate analysis, low shear rate and high shear rate of WBV were associated independently with nondipping pattern in patients with essential hypertension. Conclusion: As a simple, inexpensive and noninvasive tool, WBV seems to be a significant predictor of nondipping hypertension.

The Role of Nocturnal Blood Pressure and Sleep Quality in Hypertension Management

The accurate measurement, prediction and treatment of high blood pressure (BP) are essential to the management of hypertension and the prevention of its associated cardiovascular (CV) risks. However, even if BP is optimally controlled during the day, nocturnal high blood pressure may still increase the risk of CV events. The pattern of circadian rhythm of BP can be evaluated by ambulatory BP monitoring (ABPM). Night-time ABPM is more closely associated with fatal and nonfatal CV events than daytime ambulatory BP. However, the use of ABPM is limited by low availability and the fact that it can cause sleep disturbance, therefore may not provide realistic nocturnal measurements. Home blood pressure monitoring (HBPM) offers an inexpensive alternative to ABPM, is preferred by patients and provides a more realistic assessment of BP during an individual’s daily life. However, until recently, HBPM did not offer the possibility to measure nocturnal (sleep time) BP. The development and validation of new BP devices, such as the NightView (OMRON Healthcare, HEM9601T-E3) HBPM device, could overcome these limitations, offering the possibility of daytime and night-time BP measurements with minimal sleep disturbance.