Comparison of different schedules of nocturnal home blood pressure measurement using an information/communication technology-based device in hypertensive patients

Asian Expert Consensus on Nocturnal Hypertension Management

There is consistent and strong evidence that nighttime blood pressure is a better predictor of target organ damage and cardiovascular events, and the prevalence of nocturnal hypertension is high in all populations but higher in Asians than Europeans. Excessive salt intake and salt sensitivity have long been believed to be risk factors for elevated nighttime blood pressure in Asians. For various reasons, the control rate of nocturnal hypertension is low, for example, insufficient monitoring and inappropriate therapeutic regimens. With the increasing evidence and possibility of management, it is highly relevant to have thorough discussions among Asian experts and to reach a consensus on major aspects in regard to the management of nocturnal hypertension. The consensus involves 5 aspects, including definitions and diagnosis, epidemiology, risk and risk factors, treatment, and future perspectives.

Peak nocturnal home blood pressure as an early and strong novel risk factor for stroke: the practitioner-based nationwide J-HOP Nocturnal BP study

Clinical implications of high peak nighttime home blood pressure (BP) are currently unknown. This study investigated the association between peak nighttime home systolic BP (SBP) and cardiovascular events in individuals with at least one cardiovascular risk factor. In the Japan Morning Surge-Home Blood Pressure (J-HOP) study, nighttime home BP was automatically measured three times each night for 14 days at baseline using a nighttime home BP monitoring device (HEM-5001, Omron Healthcare). Peak nighttime home SBP was defined as average of the highest three values over the 14-night measurement period. Cardiovascular events (stroke, coronary artery disease, heart failure, aortic dissection) were tracked over a mean follow-up period of 7.1 years. This analysis included 2545 individuals (mean age 63.3 ± 10.3 years, 49% male). After adjusting for covariates (including age, sex, and average office, morning, evening, and nighttime home SBP), stroke risk was significantly higher in individuals with peak nighttime home SBP in the highest quintile (≥149.0 mmHg) compared to the lowest quintile (<119.3 mmHg) (hazard ratio [HR] 4.24, 95% confidence interval [CI] 1.07-16.77; p = 0.039 overall and 8.92, 1.49-53.43; p = 0.017 in the subgroup with ≥6 nighttime home SBP measurements). This increased stroke risk remained significant after controlling for day-by-day average real variability of nighttime BP. The average peak nighttime home SBP cut-off value for predicting an increased risk of incident stroke was 136 mmHg. We propose that exaggerated peak nighttime home SBP, determined from ≥6 measurements, is a novel risk factor for stroke, independent of conventional office and home BP values. The exaggerated peak nighttime home systolic blood pressure (HSBP) determined from six or more measurements as a novel risk factor for stroke, independent of conventional office and home blood pressure (BP) values.

Cardiovascular Events Risk in Office-Masked Nocturnal Hypertension Defined by Home Blood Pressure Monitoring

Background

Nocturnal home blood pressure monitoring (HBPM) may identify people at higher cardiovascular disease (CVD) risk than expected.

Objectives

The aim of this study was to examine the association between office-masked nocturnal hypertension, defined by HBPM, and CVD risk in a clinical practice-based population.

Methods

Prospective observational study including Japanese high cardiovascular-risk participants. Three office blood pressures (OBPs) were taken on two different occasions. Nocturnal home blood pressure (HBP) was measured three times per night for 2 weeks. The association between office-masked nocturnal hypertension and time to first CVD events (fatal and nonfatal stroke or coronary heart disease) was examined using Cox regression.

Results

The cohort included 2,545 participants who were followed for a median of 7.8 years (18,116 person-years), during which 152 CVD events occurred. The proportions of participants with nocturnal normotension (OBP <140/90 mm Hg and nocturnal HBP <120/70 mm Hg), white-coat nocturnal hypertension (OBP ≥140/90 mm Hg and nocturnal HBP <120/70 mm Hg), office-masked nocturnal hypertension (OBP <140/90 mm Hg and nocturnal HBP ≥120/70 mm Hg), and sustained nocturnal hypertension (OBP ≥140/90 mm Hg and nocturnal HBP ≥120/70 mm Hg) were 25.3%, 14.4%, 23.2%, and 37.1%, respectively. Relative to nocturnal normotension, those with both office-masked nocturnal hypertension (adjusted HR: 1.72; 95% CI: 1.01-2.92) and sustained nocturnal hypertension (adjusted HR: 1.75; 95% CI: 1.03-2.96) had similarly increased CVD risk, even after adjustment for daytime HBP values.

Conclusions

Screening for office-masked nocturnal hypertension with HBPM identifies a potentially important group of patients with increased risk for incident CVD events for whom additional preventative measures may be appropriate.

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

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

Reproducibility of nighttime home blood pressure measured by a wrist-type nocturnal home blood pressure monitoring device

The authors investigated the reproducibility of nighttime home blood pressure (BP) measured by a wrist-type BP monitoring device. Forty-six hypertensive patients (mean 69.0±11.6 years, 56.5% male) self-measured their nighttime BP hourly using simultaneously worn wrist-type and upper arm-type nocturnal home BP monitoring devices at home on two consecutive nights. Using the average 7.4±1.3 measurements on the first night and the average 7.0 ± 1.8 measurements on the second night, the authors assessed the reliability and the reproducibility of nighttime BP measured on the two nights. The difference between nights in systolic BP (SBP) measured by the wrist-device was not significant (1.6±7.0 mmHg, p = .124), while the difference in diastolic BP (DBP) was marginally significant (1.4±4.9 mmHg, p = .050). The intraclass correlation coefficients (ICCs) for agreement between nights were high both in SBP and DBP average (SBP: 0.835, DBP: 0.804). Averaging only three points of SBP resulted in lower ICC values, but still indicated good correlations (ICC > 0.6). On the other hand, the correlations of the standard deviation and average real variability of SBP between nights were low, with ICCs of 0.220 and 0.436, respectively. In conclusion, the average SBP values measured on the first night were reliable even when averaging only three readings. The reproducibility of nighttime BP variability seemed inferior to that of BP average; it might be better to measure nighttime BP over multiple nights to assess BP variability. However, this hypothesis needs verification in other study population. In addition, our study population had well-controlled BP, which limits the generalizability of this findings to all hypertensive patients.

Home Blood Pressure Monitoring: Current Status and New Developments

Home blood pressure monitoring (HBPM) is a reliable, convenient, and less costly alternative to ambulatory blood pressure monitoring (ABPM) for the diagnosis and management of hypertension. Recognition and use of HBPM have dramatically increased over the last 20 years and current guidelines make strong recommendations for the use of both HBPM and ABPM in patients with hypertension. The accuracy and reliability of home blood pressure (BP) measurements require use of a validated device and standardized procedures, and good patient information and training. Key HBPM parameters include morning BP, evening BP, and the morning-evening difference. In addition, newer semi-automatic HBPM devices can also measure nighttime BP at fixed intervals during sleep. Advances in technology mean that HBPM devices could provide additional relevant data (e.g., environmental conditions) or determine BP in response to a specific trigger (e.g., hypoxia, increased heart rate). The value of HBPM is highlighted by a growing body of evidence showing that home BP is an important predictor of target organ damage, and cardiovascular disease (CVD)- and stroke-related morbidity and mortality, and provides better prognostic information than office BP. In addition, use of HBPM to monitor antihypertensive therapy can help to optimize reductions in BP, improve BP control, and reduce target organ damage and cardiovascular risk. Overall, HBPM should play a central role in the management of patients with hypertension, with the goal of identifying increased risk and predicting the onset of CVD events, allowing proactive interventions to reduce risk and eliminate adverse outcomes.

Nighttime Home Blood Pressure in Children: Association with Ambulatory Blood Pressure and Preclinical Organ Damage

[Figure: see text].

Comparison of nighttime measurement schedules using a wrist-type nocturnal home blood pressure monitoring device

We investigated the optimal nighttime home blood pressure (BP) measurement schedule for wrist BP monitoring. Fifty hypertensive patients (mean age 68.9 ± 11.3 years) self‐measured their nighttime BP hourly using a wrist‐type nocturnal home BP monitoring device at home on two consecutive nights. Using the average 7.2 ± 1.5 measurements per night, we compared the clock‐based index (average of three measurements at 2:00, 3:00, and 4:00 a.m.) and the bedtime‐based index (average of three measurements at 2, 3, and 4 h after bedtime). The clock‐based average was significantly higher than the bedtime‐based average for both systolic BP (2.7 ± 8.2 mmHg, P = .002) and diastolic BP (1.9 ± 5.1 mmHg, P < .001). Compared to the average of all measurements throughout a night (the same definition of ambulatory BP monitoring, ie, from the time point of going to bed to awakening), the clock‐based average was comparable (systolic/diastolic BP: −0.5 ± 5.5/−0.2 ± 3.7), whereas the bedtime‐based average was significantly lower (−3.3 ± 5.0/−2.1 ± 3.6). Thus, the repeated measurement of wrist‐measured nighttime BP at three clock‐based time points per night provided reliable values. Further prospective studies of larger populations are required to confirm the optimal nighttime BP measurement schedule for wrist BP monitoring for the prediction of cardiovascular events.

Clinical significance of nocturnal home blood pressure monitoring and nocturnal hypertension in Asia

Nocturnal home blood pressure (BP) monitoring has been used in clinical practice for ~20 years. The authors recently showed that nocturnal systolic BP (SBP) measured by a home BP monitoring (HBPM) device in a Japanese general practice population was a significant predictor of incident cardiovascular disease (CVD) events, independent of office and morning home SBP levels, and that masked nocturnal hypertension obtained by HBPM (defined as nocturnal home BP ≥ 120/70 mmHg and average morning and evening BP < 135/85 mmHg) was associated with an increased risk of CVD events compared with controlled BP (nocturnal home BP < 120/70 mmHg and average morning and evening BP < 135/85 mmHg). This evidence revealed that (a) it is feasible to use a nocturnal HBPM device for monitoring nocturnal BP levels, and (b) such a device may offer an alternative to ambulatory BP monitoring, which has been the gold standard for the measurement of nocturnal BP. However, many unresolved clinical problems remain, such as the measurement schedule and conditions for the use of nocturnal HBPM. Further investigation of the measurement of nocturnal BP using an HBPM device and assessments of the prognostic value are thus warranted. Asians are at high risk of developing nocturnal hypertension due to high salt sensitivity and salt intake, and the precise management of their nocturnal BP levels is important. Information and communication technology‐based monitoring devices are expected to facilitate the management of nocturnal hypertension in Asian populations.

Nighttime Blood Pressure Measured by Home Blood Pressure Monitoring as an Independent Predictor of Cardiovascular Events in General Practice

We developed an innovative automated home blood pressure (BP) monitoring method that measures BP while asleep repeatedly over several days. Our aim was to assess the predictive ability of nighttime BP obtained using the home BP device for incident cardiovascular disease (CVD) in general practice patients. We used data from the nationwide practice-based J-HOP (Japan Morning Surge-Home Blood Pressure) Nocturnal BP Study, which recruited 2545 Japanese with a history of or risk factors for CVD (mean age 63 years; antihypertensive medication use 83%). The associations between nighttime home BPs (measured at 2:00, 3:00, and 4:00 am using validated, automatic, and oscillometric home BP devices) and incident CVD, including coronary disease and stroke events, were assessed with Cox proportional hazards models. The mean±SD office, morning home, and nighttime home systolic BP (SBP)/diastolic BP were 140±15/82±10, 137±15/79±10, and 121±15/70±9 mm Hg, respectively. During a follow-up of 7.1±3.8 years (18,116 person-years), 152 CVD events occurred. A 10-mm Hg increase of nighttime home SBP was associated with an increased risk of CVD events (hazard ratios [95% CIs]: 1.201 [1.046-1.378]), after adjustments for covariates including office and morning home SBPs. The model fit assessed by the change in Goodness-of-Fit was improved when we added nighttime home SBP into the base models including office and morning home SBPs (Δ6.838 [5.6%]; P=0.009). This is among the first and largest nationwide practice-based study demonstrating that nighttime SBP obtained using a home device is a predictor of incident CVD events, independent of in-office and morning in-home SBP measurement. Clinical Trial Registration- URL: http://www.umin.ac.jp/icdr/index.html . Unique identifier: UMIN000000894.