Nocturnal dipping status and the association of morning blood pressure surge with subclinical target organ damage in untreated hypertensives

The effects of morning versus evening high-intensity interval exercise on the magnitude of the morning blood pressure surge

Blood pressure (BP) follows a circadian rhythm, dipping during sleep and surging in the morning. A larger morning BP surge is an independent predictor of cardiovascular events. Acute exercise can produce sustained periods of post-exercise hypotension that last up to 24 h; however, the timing of exercise (morning vs. evening) may influence this response. Whether the timing of exercise influences the morning BP surge remains unknown. The current study investigated the effects of a bout of high-intensity interval exercise (HIIE) performed in the morning versus evening on the magnitude of the morning BP surge in young healthy adults. Twenty-six young, otherwise healthy adults (23 ± 4 years; 15 females) completed a randomized crossover trial where, on different days, they completed a no exercise control visit or performed either morning (0800-1000 h) or evening (1700-1900 h) HIIE. Following each visit, ambulatory BP was assessed in 30 min intervals for 24 hrs. HIIE at either time did not alter the magnitude of the morning BP surge compared to control values (control: 22 ± 5 mmHg; morning exercise: 20 ± 8 mmHg; evening exercise: 22 ± 10 mmHg, P = 0.40) or when grouped separately by sex (visit × sex P = 0.42). A positive correlation existed between Morningness-Eveningness Questionnaire score and the change in nighttime BP following both exercise times (both r = 0.42 and P = 0.04). These findings suggest that HIIE does not attenuate the morning BP surge in young healthy adults and that chronotype can predict nighttime BP responses following HIIE, irrespective of exercise time of day. This study was registered on ClinicalTrials.gov (NCT06702930).

Characteristic of 24-Hour Blood Pressure Dipping Patterns in Hypertensive Stroke Patients

Objective

We conducted a study titled for Investigation on the characteristics of 24-hour blood pressure (BP) dipping patterns in hypertensive stroke patients.

Methods

Descriptive research, analysis, and comparison, the research was conducted from July 2019 to September 2020 at the Vietnam Heart Institute - Bach Mai Hospital. There are 100 patients diagnosed with idiopathic hypertension who were divided into two groups (without stroke complications and another group with chronic stroke complications > 6 weeks), both groups were similar in age (45-64 years old).

Results

The daytime systolic BP (SBP) indices, 24-hour BP including SBP, diastolic BP (DBP), and mean arterial pressure (MAP), and particularly night-time BP indices were elevated in the stroke group compared with those without stroke complications (p < 0.05); there were no significant differences observed in daytime DBP and MAP between the two groups. SBP indices were higher in those with hemorrhage stroke compared with those with ischemic stroke, albeit without statistical significance. The prevalence of non-dipper was significantly higher in the stroke group compared with the non-stroke group (p < 0.001).

Conclusion

The daytime SBP indices, 24-hour BP (SBP, DBP, MAP), and particularly night-time BP indices were elevated in the stroke group compared with those without stroke complications. The prevalence of non-dipper was significantly higher in the stroke group compared with the non-stroke group.

Study of nycthemeral variations in blood pressure in patients with non-arteritic anterior ischemic optic neuropathy

PURPOSE

The objective of this study was to analyze the nycthemeral variations in blood pressure (BP) in individuals who presented with non-arteritic anterior ischemic optic neuropathy (NAION).

METHODS

BP was recorded for 24 h (ambulatory blood pressure monitoring, ABPM) in 65 patients with acute NAION. Three definitions of nighttime periods were used: definition 1, 1 a.m.-6 a.m.; definition 2, 10 p.m.-7 a.m.; and definition 3, 10 p.m.-8 a.m. For each of these definitions, patients were classified according to the value of nocturnal reduction in BP into dippers (10-20%), mild dippers (0-10%), reverse dippers (< 0%), and extreme dippers (> 20%).

RESULTS

The proportions of dippers, mild dippers, reverse dippers, and extreme dippers varied significantly depending on the definition chosen. We found the highest number of patients with extreme dipping (23%) when using the strictest definition of nighttime period (definition 1, 1 a.m.-6 a.m.), as compared with 6.2% and 1.5% for the other definitions, respectively. Overall, 13 of 33 patients without known systemic hypertension (39%) were diagnosed with hypertension after ABPM. No risk factor for NAION was associated with the extreme-dipping profile. Finally, the prevalence of systemic hypertension was high (69%).

CONCLUSION

In our population of patients who had an episode of NAION, the proportion of extreme dippers was higher than that usually found in the literature. However, extreme dipping is not a frequent feature of patients with NAION as compared to patients with systemic hypertension. ABPM is recommended for all patients with NAION and unknown history of systemic hypertension.

The Option of Chronotherapy of Hypertension

The aim of the present paper is to explore the option of chronotherapy of hypertension and its effectiveness in blood pressure (BP) lowering compared with its standard daily treatment. The treatment of BP has gone through many different schemes over the years. From no treatment in the early 1930s, to step care, to multiple drug combinations, or to single daily drug combinations with 2-3 drugs, still BP is not well controlled in a significant number of patients. Recently, the role of the circadian rhythm in the treatment of hypertension has been tested by several studies comparing the evening versus the morning drug administration with no clear evidence of superiority of either mode of drug administration. However, in cases of morning surge of BP, nocturnal hypertension, and renal disease, the evening drug administration has been more effective than the morning drug administration, and thus, more preferable. In order to get a better perspective on this approach of hypertension treatment, a Medline search of the English literature was contacted between 2010 and 2023 using the terms BP control, circadian rhythm, morning drug administration, evening drug administration, and 38 pertinent papers were selected for analysis. Careful review of the selected papers showed that chronotherapy of hypertension is effective. However, the overall effectiveness of evening drug administration compared with the morning administration is not significantly more effective compared to the morning administration and more work is needed in this field.

Effects of aerobic exercise on ambulatory blood pressure responses to acute partial sleep deprivation: impact of chronotype and sleep quality

Blood pressure (BP) follows a circadian rhythm intertwined with the sleep-wake cycle. Acute partial sleep deprivation (PSD; sleep ≤ 6 h) can increase BP, associated with increased cardiovascular risk. Acute exercise can reduce BP for up to 24 h, a phenomenon termed postexercise hypotension. The present study tested whether aerobic exercise could mitigate the augmented 24-h ambulatory BP caused by acute PSD. Twenty-four young otherwise healthy adults (22 ± 3 yr; 14 females; self-reported chronotypes: 6 early/10 intermediate/8 late; Pittsburgh sleep quality index: 17 good/7 poor sleepers) completed a randomized crossover trial in which, on different days, they slept normally (2300-0700), restricted sleep [0330-0700 (PSD)], and cycled for 50 min (70-80% predicted heart rate maximum) before PSD. Ambulatory BP was assessed every 30 min until 2100 the next day. Acute PSD increased 24-h systolic BP (control 117 ± 9 mmHg, PSD 122 ± 9 mmHg; P < 0.001) and prior exercise attenuated (exercise + PSD 120 ± 9 mmHg; P = 0.04 vs. PSD) but did not fully reverse this response (exercise + PSD, P = 0.02 vs. control). Subgroup analysis revealed that the 24-h systolic BP reduction following exercise was specific to late types (PSD 119 ± 7 vs. exercise + PSD 116 ± 6 mmHg; P < 0.05). Overall, habitual sleep quality was negatively correlated with the change in daytime systolic BP following PSD (r = -0.56, P < 0.01). These findings suggest that the ability of aerobic cycling exercise to counteract the hemodynamic effects of acute PSD in young adults may be dependent on chronotype and that habitual sleep quality can predict the daytime BP response to acute PSD.NEW & NOTEWORTHY We demonstrate that cycling exercise attenuates, but does not fully reverse, the augmented 24-h ambulatory blood pressure (BP) response caused by acute partial sleep deprivation (PSD). This response was primarily observed in late chronotypes. Furthermore, daytime BP after acute PSD is related to habitual sleep quality, with better sleepers being more prone to BP elevations. This suggests that habitual sleeping habits can influence BP responses to acute PSD and their interactions with prior cycling exercise.

Impact of Environmental Factors on Hypertension and Associated Cardiovascular Disease

Hypertension is the primary cause of cardiovascular diseases and is responsible for nearly 9 million deaths worldwide annually. Increasing evidence indicates that in addition to pathophysiologic processes, numerous environmental factors, such as geographic location, lifestyle choices, socioeconomic status, and cultural practices, influence the risk, progression, and severity of hypertension, even in the absence of genetic risk factors. In this review, we discuss the impact of some environmental determinants on hypertension. We focus on clinical data from large population studies and discuss some potential molecular and cellular mechanisms. We highlight how these environmental determinants are interconnected, as small changes in one factor might affect others, and further affect cardiovascular health. In addition, we discuss the crucial impact of socioeconomic factors and how these determinants influence diverse communities with economic disparities. Finally, we address opportunities and challenges for new research to address gaps in knowledge on understanding molecular mechanisms whereby environmental factors influence development of hypertension and associated cardiovascular disease.

Different Factors Associated with Morning Blood Pressure Surge in Antihypertensive-Naïve Dipper and Non-Dipper Subjects

The relationship between the morning blood pressure surge (MBPS) and cardiovascular risk is inconclusive. Previous studies have not taken into consideration dipping status in examining the MBPS and its associated factors. The aim was to examine factors associated with the MBPS in dippers and non-dippers. The MBPS was calculated by data obtained from ambulatory blood pressure monitoring, using the definition of sleep-trough morning surge. Dipping systolic blood pressure (DipSBP) was defined as [1 - (SBPsleeping/SBPawake)] × 100%. The value in milliseconds of standard deviation of normal-to-normal RR interval after waking up (SDNNaw) was calculated during the 2 h period after waking up. A total of 140 eligible subjects were divided into dippers (n = 62) and non-dippers (n = 78). Multiple regression analysis on data for all subjects revealed different correlations with the MBPS: positive in age, body mass index (BMI), and DipSBP, and inverse in cholesterol/high density lipoprotein-cholesterol (HDL-C) ratio, fasting blood glucose, and 2 h SDNNaw. When dippers were examined separately, age, female gender, and BMI correlated positively with MBPS, while cholesterol/HDL-C ratio and 2 h SDNNaw correlated negatively. For non-dippers, only age was associated with the MBPS. The factors associated with the MBPS were different for dippers and non-dippers. The MBPS seems to be a physiological response in this dipper group because age and BMI correlated positively with the MBPS, while parasympathetic neural activity after waking up and cholesterol/HDL-C ratio showed inverse correlations.

Early Left Ventricular Dysfunction and Non-Dipping: When Ejection Fraction is Not Enough. A Meta-Analysis of Speckle tracking Echocardiography Studies

BACKGROUND

There is evidence that a reduced nocturnal fall in blood pressure (BP) entails an increased risk of hypertensive-mediated organ damage (HMOD) and cardiovascular events. Most studies focusing on left ventricular (LV) systolic function, assessed by conventional LV ejection fraction (LVEF) in non-dippers compared to dippers failed to detect significant differences. To provide a new piece of information on LV systolic dysfunction in the non-dipping setting, we performed a meta-analysis of speckle tracking echocardiography (STE) studies investigating LV global longitudinal strain (GLS), a more sensitive index of LV systolic function.

METHODS

A computerized search was performed using PubMed, OVID, EMBASE, and Cochrane library databases from inception until 31 July, 2022. Full articles reporting data on LV GLS and LVEF in non-dippers and dippers were considered suitable.

RESULTS

A total of 648 non-dipper and 530 dipper individuals were included in 9 studies. LV GLS was worse in non-dipper than in their dipper counterparts (-18.4 ± 0.30 vs. -20.1 ± 0.23%, standard means difference [SMD]: 0.73 ± 0.14, confidence interval [CI]: 0.46/1.00, P < 0.0001) whereas this was not the case for LVEF (61.4 ± 0.8 and 62.0 ± 0.8%, respectively), SMD: --0.15 ± 0.09, CI: -0.32/0.03, P = 1.01). A meta-regression analysis between nighttime systolic BP and myocardial GLS showed a significant, relationship between these variables (coefficient 0.085, P < 0.0001).

CONCLUSIONS

Our findings suggest that early changes in LV systolic function not detectable by conventional echocardiography in the non-dipping setting can be unmasked by STE; implementation of STE in current practice may improve the detection of HMOD of adverse prognostic significance in individuals with altered circadian BP rhythm.

Vitamin D Deficiency in Children With Vasovagal Syncope Is Associated With Impaired Circadian Rhythm of Blood Pressure

BACKGROUND

Vitamin D deficiency is associated with the risk of cardiovascular diseases. We aimed to investigate the serum vitamin D levels in children with vasovagal syncope (VVS) and explore the correlation of vitamin D status and circadian rhythm of blood pressure in VVS pediatric patients.

METHODS

This was a retrospective study. 130 syncopal children diagnosed with VVS were included in the study. 110 age and gender matched healthy individuals were enrolled as control. According to serum 25(OH)D levels, VVS patients were divided into vitamin D sufficient group and vitamin D deficient group. Detailed information of VVS children with vitamin D deficiency and sufficiency on demographic data, baseline laboratory testing, echocardiogram, ambulatory blood pressure monitoring, and Holter ECG recording were extracted and analyzed.

RESULTS

VVS children had a higher prevalence of vitamin D deficiency compared with healthy individuals (33.8% vs. 20.0%, P = 0.017). VVS patients with vitamin D deficiency had a higher rate of non-dipper blood pressure (79.5% vs. 59.3%, P = 0.021) and a lower value of square root of mean squared differences of successive normal to normal intervals (rMSSD) (median 107.8 vs. 141.0 ms, P = 0.035) compared with those with vitamin D sufficiency. Logistic regression analysis showed that non-dipper blood pressure was associated with serum 25(OH)D level [OR = 0.979, 95% CI (0.960, 0.999), P = 0.036].

CONCLUSION

VVS pediatric patients had a higher prevalence of vitamin D deficiency. VVS children with vitamin D deficiency showed a higher rate of non-dipper blood pressure, suggesting that vitamin D deficiency is correlated with impaired circadian rhythm of blood pressure.

Difference between morning and evening home blood pressure and cardiovascular events: the J-HOP Study (Japan Morning Surge-Home Blood Pressure)

Little is known about the relationship of the difference between morning and evening systolic blood pressure (BP) (MEdif) in home BP with cardiovascular disease (CVD) incidence. To assess this relationship, we used data from the nationwide practice-based J-HOP (Japan Morning Surge-Home BP) study, which recruited 4258 cardiovascular risk participants (mean age 64.9 years; 46.8% men; 79.2% using antihypertensive medications) who underwent morning and evening home BP monitoring using a validated, automated device for 14 consecutive days. During a mean ± SD follow-up of 6.2 ± 3.8 years (26,295 person-years), 269 CVD events occurred. Adjusted Cox models suggested that higher MEdif (≥20 mmHg) was associated with higher CVD risks than was medium MEdif (0-20 mmHg) independent of the average morning and evening (MEave) home systolic BP (SBP) (adjusted hazard ratio [HR]: 1.40; 95% confidence interval [CI] 1.02-1.91). We also divided participants into four BP phenotype groups as follows: "both non-elevated" (MEdif < 20 mmHg and MEave SBP < 135 mmHg), "elevated-MEdif" (MEdif ≥ 20 mmHg and MEave SBP < 135 mmHg), "elevated-MEave" (MEdif < 20 mmHg and MEave SBP ≥ 135 mmHg), and "both elevated" (MEdif ≥ 20 mmHg and MEave SBP ≥ 135 mmHg). The cumulative incidence of CVD events was higher in patients with the "elevated-MEdif," "elevated-MEave," and "both elevated" phenotypes than in those with the "both non-elevated" phenotype. After adjusting for covariates, the "both elevated" phenotype was associated with higher CVD risk than the "both non-elevated" phenotype (adjusted HR: 1.64; 95% CI: 1.09-2.46). This is the first study demonstrating a direct correlation between CVD outcomes and the difference between morning and evening home SBP.

Reverse dipping and subclinical cardiac organ damage: a meta-analysis of echocardiographic studies

AIM

Available evidence on the association between reverse dipping pattern and subclinical cardiac damage is scanty. We performed a systematic meta-analysis of echocardiographic studies in order to provide an updated and comprehensive information on this issue.

METHODS

The PubMed, OVID-MEDLINE, and Cochrane library databases were analyzed to search English-language articles published from January from the inception up to 31 July 2020. Studies were identified by using MeSH terms and crossing the following search items: 'reverse dipping', 'nondipping', 'inverted dipping', 'ambulatory blood pressure', 'cardiac damage', 'hypertensive heart disease', 'left ventricular mass', 'left ventricular hypertrophy', and 'echocardiography'.

RESULTS

Data from 14 studies including 1429 patients with reverse dipping, 2584 dippers and 3508 nondippers were considered. Left ventricular (LV) mass index and relative wall thickness were greater in reverse dippers than in dippers (SMD: 0.40 ± 0.04 g/m2, P < 0.0001; 0.31 ± 0.07, P < 0.0001) and nondippers (SMD: 0.25 ± 0.04 g/m2, P < 0.0001; 0.21 ± 0.07, P = 0.004). The reverse dipping group had an increased risk of LV hypertrophy compared with dipping (OR = 1.85, CI 1.47-2.32, P < 0.0001) and nondipping group (OR = 1.45, CI 1.19-1.78, P < 0.0001). A significant progressive reduction in the E/A ratio, paralleled by an increase in left atrium diameter occurred from dippers, to nondippers and reverse dippers.

CONCLUSION

The present meta-analysis provides a novel piece of information about the unfavourable association between the reverse dipping pattern and subclinical cardiac alterations and suggests that the detection of this blood pressure phenotype may identify individuals at increased risk for subclinical organ damage.

Reproducibility study of nocturnal blood pressure dipping in patients with high cardiovascular risk

It has been shown that in most people there is a physiological reduction in blood pressure during nighttime sleep, it falling by approximately 10% compared to daytime values (dippers). On the other hand, in some people, there is no nighttime reduction (non‐dippers). Various studies have found an association between being a non‐dipper and a higher risk of cardiovascular disease, but few have assessed whether the nocturnal pattern is maintained over time. From the database of the TAHPS study, data were available on 225 patients, each of whom underwent 24‐hour ambulatory blood pressure monitoring (ABPM) on four occasions over a period of 5 months. We studied the reproducibility of the nocturnal BP dipping pattern with mixed linear analysis and also calculated the concordance in the classification of patients as dippers or non‐dippers. The intraclass correlation coefficients between the different ABPM recordings were 0.482 and 0.467 for systolic and diastolic blood pressure, respectively. Two‐thirds (67%) and 70% of the patients classified, respectively, as dippers or non‐dippers based on systolic and diastolic blood pressure readings in the first ABPM recording were found to have the same classification based on the subsequent recordings. We conclude that the reproducibility of nocturnal dipping patterns and concordance of dipper vs non‐dipper status in individual patients is modest and therefore that we should be cautious about recommending treatments or interventions based on these patterns.

Ambulatory blood pressure monitoring in children undergoing polysomnography

Ambulatory blood pressure monitoring (ABPM) is recommended for the diagnosis of hypertension in children at high risk, such as children with obesity or obstructive sleep apnea (OSA). Nocturnal hypertension is highly predictive of cardiovascular outcomes. ABPM allows for early detection of nocturnal hypertension in children. Although OSA is the most common sleep disorder associated with hypertension, studies have also shown an increase in cardiovascular risk in adult patients with other sleep disorders; therefore, there is an imperative need to provide early diagnosis in children at high risk. In the present study, we evaluated the feasibility of using ABPM during polysomnography (PSG) in children referred for sleep disordered breathing to the Seattle Children's Hospital Sleep Disorders Center. A total of 41 children aged 7-18 years were included in this study. The ABPM monitor was worn for a mean (SD) of 10.2 (1.5) hr. No significant changes were seen in PSG parameters when ABPM was co-performed with PSG, including sleep efficiency and arousals. In total, 12 of the 41 patients were identified as having nocturnal hypertension. Our study is important in that it shows that concomitant use of ABPM during PSG can aid in the early identification of nocturnal hypertension in this population.

Peak blood pressure-guided monitoring may serve as an effective approach for blood pressure control in the out-of-office setting

We aimed to explore whether diurnal blood pressure (BP) peak characteristics have a significant influence on the association between left ventricular damage with the two BP components (morning BP vs. afternoon peak BP) in untreated hypertensives. This cross-sectional study included 1084 hypertensives who underwent echocardiography and 24-h ambulatory BP monitoring. Participants were stratified according to the relationship between morning systolic BP (MSBP; average SBP within 2 h of waking up) and afternoon peak systolic BP (ASBP; average SBP between 16:00 and 18:00). Afternoon and morning hypertension was defined as ≥ 135/85 mm Hg. The morning and afternoon peak BPs occurred at around 7:00 and 17:00, respectively. In general hypertensives, morning BP and afternoon peak BP are significantly different in absolute values (for binary SBP, McNemar's χ²  = 6.42; p = .014). ASBP was more pronounced than MSBP in 602 patients (55.5%), in whom 24-h SBP showed higher consistency with ASBP than with MSBP (Kappa value: 0.767 vs 0.646, both p < .01). In subjects with ASBP ≥ MSBP, ASBP was associated with left ventricular hypertrophy independent of MSBP (logistic regression analysis odds ratio: 1.046, p < .01), and left ventricular mass index was more strongly correlated with ASBP than with MSBP (multiple regression coefficient β: 0.453, p < .01), in which the relationships held true independently of 24-h SBP. The opposite results were obtained in subjects with MSBP > ASBP. Peak BP-guided monitoring may serve as an effective approach to out-of-office hypertension monitoring and control, providing the best consistency with 24-h average SBP and highest discrimination performance for target organ damage, independently of 24-h SBP.

The disadvantage of morning blood pressure management in hypertensive patients

To investigate whether the control of morning blood pressure (MBP) reflects the control of blood pressure (BP) in other periods (daytime, nighttime and 24-hour) and to assess whether morning BP displays a closer association with subclinical target organ damage (TOD) than the BP measured in other periods.One thousand one hundred forty patients with primary hypertension who completed subclinical TOD detection and 24-hour ambulatory BP monitoring were included in the analysis. Pearson correlation analysis, Kappa consistency test, multiple linear regression analysis, and area under the receiver operating curve were used to analyze the data.Morning BP and daytime BP displayed good agreement, but not 24-hour BP , particularly the nighttime BP (all P < .001). Approximately 39.4% of the hypertensive patients receiving drug treatment who had achieved control of the morning BP presented masked nocturnal hypertension, which was associated with worse subclinical TOD. The BP measured in all periods correlated with subclinical TOD, and the correlation was more obvious in the treatment subgroup. However, morning BP did not independently affect subclinical TOD. Morning BP appeared to exhibit less discriminatory power than nighttime BP, particularly with respect to the urinary albumin to creatinine ratio.The use of morning BP for monitoring during hypertension management may not be enough. Masked uncontrolled nocturnal hypertension should be screened when morning BP is controlled.