Diurnal blood pressure variation and related behavioral factors. Hypertens Res. 2011;34:281-285. [PMID: 21124325 DOI: 10.1038/hr.2010.241]

Prediction of cardiovascular risk factors from retinal fundus photographs: Validation of a deep learning algorithm in a prospective non-interventional study in Kenya

AIM

Hypertension and diabetes mellitus (DM) are major causes of morbidity and mortality, with growing burdens in low-income countries where they are underdiagnosed and undertreated. Advances in machine learning may provide opportunities to enhance diagnostics in settings with limited medical infrastructure.

MATERIALS AND METHODS

A non-interventional study was conducted to develop and validate a machine learning algorithm to estimate cardiovascular clinical and laboratory parameters. At two sites in Kenya, digital retinal fundus photographs were collected alongside blood pressure (BP), laboratory measures and medical history. The performance of machine learning models, originally trained using data from the UK Biobank, were evaluated for their ability to estimate BP, glycated haemoglobin, estimated glomerular filtration rate and diagnoses from fundus images.

RESULTS

In total, 301 participants were enrolled. Compared with the UK Biobank population used for algorithm development, participants from Kenya were younger and would probably report Black/African ethnicity, with a higher body mass index and prevalence of DM and hypertension. The mean absolute error was comparable or slightly greater for systolic BP, diastolic BP, glycated haemoglobin and estimated glomerular filtration rate. The model trained to identify DM had an area under the receiver operating curve of 0.762 (0.818 in the UK Biobank) and the hypertension model had an area under the receiver operating curve of 0.765 (0.738 in the UK Biobank).

CONCLUSIONS

In a Kenyan population, machine learning models estimated cardiovascular parameters with comparable or slightly lower accuracy than in the population where they were trained, suggesting model recalibration may be appropriate. This study represents an incremental step toward leveraging machine learning to make early cardiovascular screening more accessible, particularly in resource-limited settings.

Diurnal Variation in Choroidal Parameters Among Healthy Subjects Using Wide-Field Swept-Source Optical Coherence Tomography Angiography

Purpose

The purpose of this study was to evaluate the diurnal variation in choroidal parameters in a wide field area among healthy subjects and to identify correlations between choroidal luminal area and stromal area and various systemic factors.

Methods

In this cross-sectional study, 42 eyes from 21 healthy participants (mean age = 32.4 ± 8.8 years) were examined using wide-field swept-source optical coherence tomography angiography (WF SS-OCTA, 24 mm × 20 mm). Measurements of choroidal parameters, including choroidal volume (CV), choroidal thickness (CT), choroidal vessel volume (CVV), and choroidal stromal volume (CSV), were taken at 8:00, 12:00, 18:00, and 22:00. Systemic factors, such as blood pressure and heart rate, were concurrently monitored.

Results

Our study observed significant diurnal variations in the mean total CV, CT, CVV, and CSV, with minimum measurements around 12:00 (P < 0.001) and peak values at 22:00 (P < 0.001). Furthermore, changes in CV in specific regions were more closely associated with fluctuations in CVV than CSV in the same regions. No significant diurnal variations were found in systolic (P = 0.137) or diastolic blood pressure (P = 0.236), whereas significant variations were observed in the heart rate (P = 0.001).

Conclusions

Our study reveals diurnal variations in choroidal parameters and their associations, emphasizing that changes in choroidal volume relate more to the luminal than the stromal area in vessel-rich regions. This enhances our understanding of choroidal-related ocular diseases.

Translational Relevance

Regions with higher choroidal vasculature observed greater choroidal volume changes.

Examining the Pre- and Post-percutaneous Coronary Intervention Blood Pressure Variability Using Ambulatory Blood Pressure Monitoring in Patients With Stable and Unstable Coronary Artery Disease

Introduction The World Health Organization has drawn attention to the fact that coronary artery disease (CAD) is our modern "epidemic." Nowadays, sudden death during sleep has become prevalent due to a lack of oxygen supply to the heart. CAD causes more deaths and disabilities and incurs greater economic costs than any other illness in the developed world. The prevalence of cardiovascular disorders and heart disease is on the rise in India. Hypertension is one of the leading risk factors for all cardiovascular diseases. This study aims to compare blood pressure variability before and after percutaneous coronary intervention (PCI), using ambulatory blood pressure monitoring (ABPM) in patients with stable and unstable CAD. Materials and methods This prospective observational study was conducted among 52 patients with stable and unstable CAD, admitted to the medicine department, who required PCI at a tertiary care hospital. Before and after PCI, the same antihypertensive drugs were orally administered. ABPM was performed before PCI and one day after PCI. ABPM was conducted every 30 minutes during the day and every 60 minutes during the night over a 24-hour period using a mobil-o-graph (IEM, Germany). The results of the observed parameters were analyzed using the HMS Client-Server 4.0 system (Informer Technologies, Inc., Los Angeles, USA). The collected data were analyzed using SPSS Statistics version 21.0 software (IBM Corp. Released 2012. IBM SPSS Statistics for Windows, Version 21.0. Armonk, NY: IBM Corp.). Results Out of 52 patients, 28 (53.8%) had stable CAD and 24 (46.2%) had unstable CAD. The mean age of patients with stable and unstable CAD was 56.64±9.44 and 57.04±12.36 years, respectively. The majority of patients with stable (67.9%) and unstable CAD (62.5%) were males. Various other variables were considered, such as lipid profile, blood sugar, cardiac troponin-I, and medical history, including hypertension and type 2 diabetes mellitus. Among stable CAD patients, a comparison between pre- and post-PCI systolic blood pressure (SBP) did not show a significant difference in all SBP measurements (p>0.05). However, the mean diurnal index was significantly lower following PCI compared to before PCI (p=0.019). Among unstable CAD patients, a comparison between pre- and post-PCI SBP showed a significant change in peak daytime, average daytime, and diurnal index (p<0.05). For all other SBP measurements, the difference between pre- and post-PCI measurements was not statistically significant (p>0.05). In patients with stable CAD, a statistically significant change in diastolic blood pressure (DBP) following PCI was observed for peak daytime, peak nighttime, and average nighttime values. In contrast, for patients with unstable CAD, a statistically significant change in DBP following PCI was observed for peak daytime, peak nighttime, and minimum daytime values (p<0.05). Statistically, post-PCI, there was no significant difference between the two groups for SBP and DBP measurements (p>0.05). Additionally, there was no significant difference between the two groups pre- and post-PCI in the pattern of dipping. Conclusion A comparison of the ABPM before and after PCI showed that, within 48 hours post-PCI, the ambulatory blood pressure indicators did not differ statistically from those before PCI.

Fragmented Ventricular Complexes and Blood Pressure Variability Assessed by Ambulatory Blood Pressure Monitoring in Patients With Metabolic Syndrome

Introduction Hypertension is a leading risk factor for the development of cardiovascular and metabolic derangements. In patients with metabolic syndrome (MetS), hypertension is one of the cornerstones showing high variability which is detected in ambulatory blood pressure monitoring. Fragmented ventricular complexes on ECG are seen as hypertensives and are a viable and easy measure of myocardial fibrosis even in the absence of obvious hypertrophy. Aim The present study was undertaken to study the blood pressure variability in patients of MetS with fragmented QRS (fQRS) versus normal ventricular complexes (QRS). Results Out of 100 patients, 22 (22%) had fQRS complexes. Hypertension and diabetes were the most prevalent associated in both groups but a difference was seen with coronary artery disease, which was significantly associated in the fQRS group (8.97% vs 95.45%, p<0.001) as compared to the non-fQRS group. Significant differences were observed in waist circumference (p=0.019), triglyceride (p=0.006) and left ventricular ejection fraction (p<0.001) between the two groups. There was a marked difference (p<0.05) between heart rate variability during day and night time between normal and fQRS sub-groups, being higher in the latter. A similar pattern of change was observed for systolic and diastolic blood pressures and associated dipping. Conclusion Significant differences exist between heart rate and blood pressure changes in patients with fQRS of MetS, thus making fQRS a potent indicator of cardiovascular status.

Orthostatic Hypotension in Adults With Hypertension: A Scientific Statement From the American Heart Association

Although orthostatic hypotension (OH) has long been recognized as a manifestation of autonomic dysfunction, a growing body of literature has identified OH as a common comorbidity of hypertension. This connection is complex, related to pathophysiology in blood pressure regulation and the manner by which OH is derived as the difference between 2 blood pressure measurements. While traditional therapeutic approaches to OH among patients with neurodegenerative disorders focus on increasing upright blood pressure to prevent cerebral hypoperfusion, the management of OH among patients with hypertension is more nuanced; resting hypertension is itself associated with adverse outcomes among these patients. Although there is substantial evidence that intensive blood pressure treatment does not cause OH in the majority of patients with essential hypertension, some classes of antihypertensive agents may unmask OH in patients with an underlying autonomic impairment. Practical steps to manage OH among adults with hypertension start with (1) a thorough characterization of its patterns, triggers, and cause; (2) review and removal of aggravating factors (often pharmacological agents not related to hypertension treatment); (3) optimization of an antihypertensive regimen; and (4) adoption of a tailored treatment strategy that avoids exacerbating hypertension. These strategies include countermaneuvers and short-acting vasoactive agents (midodrine, droxidopa). Ultimately, further research is needed on the epidemiology of OH, the impact of hypertension treatment on OH, approaches to the screening and diagnosis of OH, and OH treatment among adults with hypertension to improve the care of these patients and their complex blood pressure pathophysiology.

Assessing cardiorespiratory fitness in clinical and community settings: Lessons and advancements in the 100th year anniversary of VO2max

Cardiorespiratory fitness (CRF) is a well-established biomarker that has applications to all adults across the health and disease spectrum. Despite overwhelming evidence supporting the prognostic utility of CRF, it remains vastly underutilized. CRF is optimally measured via cardiopulmonary exercise testing which may not be feasible to implement on a large scale. Therefore, it is prudent to develop ways to accurately estimate CRF that can be applied in clinical and community settings. As such, several prediction equations incorporating non-exercise information that is readily available from routine clinical encounters have been developed that provide an adequate reflection of CRF that could be implemented to raise awareness of the importance of CRF. Further, technological advances in smartphone apps and consumer-grade wearables have demonstrated promise to provide reasonable estimates of CRF that are widely available, which could enhance the utilization of CRF in both clinical and community settings.

The Role of Circadian Rhythms in Stroke: A Narrative Review

Stroke, a debilitating condition often leading to long-term disability, poses a substantial global concern and formidable challenge. The increasing incidence of stroke has drawn the attention of medical researchers and neurologists worldwide. Circadian rhythms have emerged as pivotal factors influencing stroke's onset, pathogenesis, treatment, and outcomes. To gain deeper insights into stroke, it is imperative to explore the intricate connection between circadian rhythms and stroke, spanning from molecular mechanisms to pathophysiological processes. Despite existing studies linking circadian rhythm to stroke onset, there remains a paucity of comprehensive reviews exploring its role in pathogenesis, treatment, and prognosis. This review undertakes a narrative analysis of studies investigating the relationship between circadian variation and stroke onset. It delves into the roles of various physiological factors, including blood pressure, coagulation profiles, blood cells, catecholamines, cortisol, and the timing of antihypertensive medication, which contribute to variations in circadian-related stroke risk. At a molecular level, the review elucidates the involvement of melatonin, circadian genes, and glial cells in the pathophysiology. Furthermore, it provides insights into the diverse factors influencing stroke treatment and outcomes within the context of circadian variation. The review underscores the importance of considering circadian rhythms when determining the timing of stroke interventions, emphasizing the necessity for personalized stroke management strategies that incorporate circadian rhythms. It offers valuable insights into potential molecular targets and highlights areas that require further exploration to enhance our understanding of the underlying pathophysiology. In comparison to the published literature, this manuscript distinguishes itself through its coverage of circadian rhythms' impact on stroke across the entire clinical spectrum. It presents a unique synthesis of epidemiological, clinical, molecular, and cellular evidence, underscoring their collective significance.

Night-Time Hot Spring Bathing Is Associated with a Lower Systolic Blood Pressure among Japanese Older Adults: A Single-Institution Retrospective Cohort Study

Hot spring bathing is practiced to help manage hypertension. We retrospectively investigated the effects of hot spring bathing on hypertension with the aim of identifying a novel approach to prevent and manage hypertension. The study cohort comprised 99 patients aged ≥65 years admitted to Kyushu University Beppu Hospital between 1 December 2021 and 30 November 2022 who could walk by themselves and who used hot springs for ≥3 days during their hospital stay. The changes in both systolic and diastolic blood pressure were significantly decreased in the night-time bathing group (n = 21) compared with the noontime (n = 26) and afternoon (n = 52) groups. Night-time hot spring bathing was significantly associated with reduced systolic blood pressure the next morning in older adults. Although prospective randomized controlled trials on night-time hot spring bathing as a hypertension treatment are warranted to investigate whether the practice can prevent hypertension among adults aged ≥65 years, we have initiated a single-center, phase II study on the relationship between sleep quality and quality of life in hypertensive patients after night-time hot spring bathing.

Association of blood pressure measurements in sitting, supine, and standing positions with the 10-year risk of mortality in Korean adults

OBJECTIVES

This prospective cohort study investigated the association between blood pressure (BP) as measured in different body postures and all-cause and cardiovascular (CV) mortality risk.

METHODS

This population-based investigation included 8,901 Korean adults in 2001 and 2002. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured sequentially in the sitting, supine, and standing positions and classified into 4 categories: 1) normal, SBP <120 mmHg and DBP <80 mmHg; 2) high normal/prehypertension, SBP 120-129 mmHg and DBP <80 mmHg/SBP 130-139 mmHg or DBP 80-89 mmHg; 3) grade 1 hypertension (HTN), with SBP 140-159 mmHg or DBP 90-99 mmHg; and 4) grade 2 HTN, SBP ≥160 mmHg or DBP ≥100 mmHg. The date and cause of individual deaths were confirmed in the death record data compiled until 2013. Data were analyzed using Cox proportional hazard regression.

RESULTS

Significant associations were found between the BP categories and all-cause mortality, but only when BPs were measured in the supine position. The multivariate hazard ratios (95% confidence intervals) were 1.36 (1.06-1.75) and 1.59 (1.06-2.39) for grade 1 and grade 2 HTN, respectively, compared with the normal category. The associations between the BP categories and CV mortality were significant regardless of body posture among participants ≥65 years, whereas they were significant for supine BP measurements only in those <65 years.

CONCLUSIONS

BP measured in the supine position predicted all-cause mortality and CV mortality better than BP measured in other postures.

Best Time of Day for Strength and Endurance Training to Improve Health and Performance? A Systematic Review with Meta-analysis

BACKGROUND

Current recommendations for physical exercise include information about the frequency, intensity, type, and duration of exercise. However, to date, there are no recommendations on what time of day one should exercise. The aim was to perform a systematic review with meta-analysis to investigate if the time of day of exercise training in intervention studies influences the degree of improvements in physical performance or health-related outcomes.

METHODS

The databases EMBASE, PubMed, Cochrane Library, and SPORTDiscus were searched from inception to January 2023. Eligibility criteria were that the studies conducted structured endurance and/or strength training with a minimum of two exercise sessions per week for at least 2 weeks and compared exercise training between at least two different times of the day using a randomized crossover or parallel group design.

RESULTS

From 14,125 screened articles, 26 articles were included in the systematic review of which seven were also included in the meta-analyses. Both the qualitative synthesis and the quantitative synthesis (i.e., meta-analysis) provide little evidence for or against the hypothesis that training at a specific time of day leads to more improvements in performance-related or health-related outcomes compared to other times. There was some evidence that there is a benefit when training and testing occur at the same time of day, mainly for performance-related outcomes. Overall, the risk of bias in most studies was high.

CONCLUSIONS

The current state of research provides evidence neither for nor against a specific time of the day being more beneficial, but provides evidence for larger effects when there is congruency between training and testing times. This review provides recommendations to improve the design and execution of future studies on this topic.

REGISTRATION

PROSPERO (CRD42021246468).

Circadian Rhythms Disrupted by Light at Night and Mistimed Food Intake Alter Hormonal Rhythms and Metabolism

Availability of artificial light and light-emitting devices have altered human temporal life, allowing 24-hour healthcare, commerce and production, and expanding social life around the clock. However, physiology and behavior that evolved in the context of 24 h solar days are frequently perturbed by exposure to artificial light at night. This is particularly salient in the context of circadian rhythms, the result of endogenous biological clocks with a rhythm of ~24 h. Circadian rhythms govern the temporal features of physiology and behavior, and are set to precisely 24 h primarily by exposure to light during the solar day, though other factors, such as the timing of meals, can also affect circadian rhythms. Circadian rhythms are significantly affected by night shift work because of exposure to nocturnal light, electronic devices, and shifts in the timing of meals. Night shift workers are at increased risk for metabolic disorder, as well as several types of cancer. Others who are exposed to artificial light at night or late mealtimes also show disrupted circadian rhythms and increased metabolic and cardiac disorders. It is imperative to understand how disrupted circadian rhythms alter metabolic function to develop strategies to mitigate their negative effects. In this review, we provide an introduction to circadian rhythms, physiological regulation of homeostasis by the suprachiasmatic nucleus (SCN), and SCN-mediated hormones that display circadian rhythms, including melatonin and glucocorticoids. Next, we discuss circadian-gated physiological processes including sleep and food intake, followed by types of disrupted circadian rhythms and how modern lighting disrupts molecular clock rhythms. Lastly, we identify how disruptions to hormones and metabolism can increase susceptibility to metabolic syndrome and risk for cardiovascular diseases, and discuss various strategies to mitigate the harmful consequences associated with disrupted circadian rhythms on human health.

Oral hygiene, mouthwash usage and cardiovascular mortality during 18.8 years of follow-up

Aim(s) We tested the following hypotheses: would better oral hygiene self-care (OHS) influence cardiovascular (CVD) mortality? Will using mouthwash in addition to OHS affect CVD mortality? How does mouthwash usage impact the oral microbes?Design and methods Among 354 dentate subjects from the Kuopio Oral Health and Heart study, the association of OHS with CVD mortality was assessed using Cox regression analyses, adjusting for age, sex, smoking, dyslipidemia, diabetes, hypertension and education. Additionally, whether using mouthwash would affect this relationship was evaluated.Results In the multivariable-adjusted models, OHS was associated with a 51% reduction in the risk of CVD mortality (hazard ratio [HR] 0.49 [0.28-0.85]; p = 0.01). Even those who had coronary artery disease at baseline showed a marginally significant benefit (0.50 [0.24-1.06]; p = 0.07). However, mouthwash usage did not change OHS effects (HR = 0.49 [0.27-0.87]; p = 0.01), indicating no additional benefits nor detriments. All tested microbes trended to decrease with mouthwash usage in the short term, but none were statistically significant.Conclusion Good OHS significantly lowered the risk of CVD mortality relative to poor OHS. Mouthwash usage did not show any long-term harm or benefit on CVD mortality beyond the benefits rendered by brushing and flossing.

The time dimension to stroke: Circadian effects on stroke outcomes and mechanisms

The circadian system is widely involved in the various pathological outcomes affected by time dimension changes. In the brain, the master circadian clock, also known as the "pacemaker," is present in the hypothalamus's suprachiasmatic nucleus (SCN). The SCN consists of molecular circadian clocks that operate in each neuron and other brain cells. These circadian mechanisms are controlled by the transcription and translation of specific genes such as the clock circadian regulator (Clock) and brain and muscle ARNT-Like 1 (Bmal1). Period (Per1-3) and cryptochrome (Cry1 and 2) negatively feedback and regulate the clock genes. Variations in the circadian cycle and these clock genes can affect stroke outcomes. Studies suggest that the peak stroke occurs in the morning after patients awaken from sleep, while stroke severity and poor outcomes worsen at midnight. The main risk factor associated with stroke is high blood pressure (hypertension). Blood pressure usually dips by 15-20% during sleep, but many hypertensives do not display this normal dipping pattern and are non-dippers. A sleep blood pressure is the primary determinant of stroke risk. This article discusses the possible mechanism associated with circadian rhythm and stroke outcomes.

Disrupted Circadian Rhythm of Epinephrine in Males With Youth-Onset Type 2 Diabetes

Context

Blood pressure and plasma catecholamines normally decline during sleep and rapidly increase in early morning. This is blunted in adults with type 2 diabetes (T2D).

Objective

We hypothesize that increased sympatho-adrenal activity during sleep differentiates youth with T2D from nondiabetic obese youth and lean youth.

Methods

Fasting spot morning and 24-hour urines were collected in obese adolescents with and without T2D, and normal-weight controls. Fractionated free urine catecholamines (epinephrine, norepinephrine, and dopamine) were measured, and the ratio of fasting spot morning to 24-hour catecholamines was calculated.

Results

Urinary 24-hour catecholamine levels were comparable across the 3 groups. Fasting morning epinephrine and the ratio of fasting morning/24-hour epinephrine were higher in youth with T2D (P = 0.004 and P = 0.035, respectively). In males, the ratio of fasting morning/24-hour epinephrine was also higher in youth with T2D (P = 0.005). In females, fasting morning norepinephrine and the ratio of fasting morning/24-hour dopamine were lower in obese youth with and without T2D (P = 0.013 and P = 0.005, respectively) compared with lean youth. Systolic blood pressure was higher in diabetic participants than other groups; males trended higher than females.

Conclusion

Circadian rhythm in catecholamines is disrupted in youth-onset T2D, with a blunted overnight fall in urinary epinephrine in males. Conversely, fasting morning norepinephrine and dopamine levels were lower in obese females with or without T2D. Higher nocturnal catecholamines in males with T2D might associate with, or predispose to, hypertension and cardiovascular complications. Lower catecholamine excretion in females with obesity might serve an adaptive, protective role.

Effects of hypotension and hypertension on source memory and working memory

OBJECTIVES

The effects of chronic low and high blood pressure on memory are unclear due to divergent results, originating in part due to participant misclassifications. The aim of this study was to compare source memory and working memory performance in individuals diagnosed with hypotension or hypertension with the performance of normotensive participants. Hypertensive and hypotensive individuals were receiving medical treatment.

METHOD

From a sample of 1656 participants, 219 were identified as hypertensive, and 37 were identified as hypotensive. Each of these two groups was compared with normotensive individuals matched by age, education and sex. Source memory performance and working memory performance were assessed through computerized tasks.

RESULTS

Source memory accuracy was poorer in hypotensive and hypertensive individuals than in normotensive individuals, and spatial working memory discrimination was inferior in hypertensive participants compared to normotensive individuals.

CONCLUSION

Blood pressure impairment should be considered a major concern because it has been linked to severe cardiovascular and cerebrovascular diseases. Furthermore, here we show that it has negative effects on the two types of memory that are most essential for preserving a self-sufficient lifestyle.

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.

Cardiorespiratory fitness as a mediator in the relationship between lung function and blood pressure in adults

It is unclear whether physical activity and cardiorespiratory fitness (CRF) are pathways that link low pulmonary function (LPF) to increased blood pressure (BP). Therefore, we investigated the extent to which CRF and moderate-to-vigorous physical activity (MVPA) mediate the relationship between LPF and high BP in adults. We conducted a cross-sectional study with 1,362 participants that underwent cardiopulmonary exercise testing (CPET), spirometry, and wore an accelerometer to determine physical activity patterns. We performed mediation analyses using structural equations considering peak oxygen uptake (V̇O₂) and MVPA as mediators, forced vital capacity (FVC) and forced expiratory volume in the first second (FEV1) as independent variables, and systolic and diastolic blood pressure (SBP, DBP) as dependent variables. The probability of alpha error was set at 5%. We found a significant total effect of FVC on SBP and DBP considering V̇O₂ as mediator (P<0.01). Indirect effects were also significant, with 42.6% of the total effect of FVC on SBP and 77% on DBP mediated by V̇O₂ (P<0.01). We did not observe a direct effect of FVC on SBP and DBP. Considering FEV1 as an independent variable, the total effect on SBP was also significant, as were the indirect effects, mediated by V̇O₂ at 14.8% for SBP and 7.6% for DBP (P<0.01). We did not find an indirect effect of FVC or FEV1 considering the MVPA as a mediator. CRF mediates the pathway that links LPF and elevated BP. Therefore, CRF is more sensitive to variations in FVC and FEV1 than MVPA.

Variability of biomarkers used for the classification of metabolic syndrome: A repeated measurements study

BACKGROUND AND AIMS

The definition of the metabolic syndrome consists of five components. The underlying measurements are subject to intra-individual variability. This repeated measurements study investigated the impact of intra-individual measurement variability on the stability of the diagnosis of metabolic syndrome over 12 months.

METHODS AND RESULTS

Twenty-five employees of the University Medicine Greifswald aged 22-70 years were examined once a month over one year. Examinations included blood sampling and anthropometric and blood pressure measurements. Laboratory measurements included glucose, cholesterol (high-density lipoprotein [HDL], and low-density lipoprotein [LDL]), and triglycerides. The metabolic syndrome was defined according to the International Diabetes Federation modified for non-fasting blood samples. Variations in continuous metabolic markers were assessed using coefficients of variation (CV) and intra-class correlation coefficients (ICC). Overall eight participants (32%) were categorized at least once within 12 months as having a metabolic syndrome; in none of those metabolic syndrome was found consistently over the study follow-ups. The Cohen's Kappa for metabolic syndrome was 0.57. CV was highest for triglycerides (27.5%) followed by glucose (10.1%), LDL- (9.5%), and HDL-cholesterol (8.6%). ICC's were lowest for glucose (0.51), triglycerides (0.65), systolic (0.68), and diastolic blood pressure (0.69).

CONCLUSION

We showed that the measurement of biomarkers defining the metabolic syndrome is a time-varying condition with implications for the concept of the metabolic syndrome. To account for this uncertainty in prevalence studies we propose to identify uncertain cases according to the current definition of the metabolic syndrome. For analysing associations we recommend to apply probabilistic sensitivity analyses.

Chronobiological Patterns of Aneurysmal Subarachnoid Hemorrhage in Central China

Background:

Aneurysmal subarachnoid hemorrhage (aSAH) is an acute and sometimes fatal cerebrovascular disease. The chronobiological patterns of aSAH are still unclear worldwide. This 15-year time-series study aims to clarify the chronobiological patterns including seasonal, monthly, weekly, and circadian distributions of aSAH.

Methods:

We retrospectively analyzed the medical records of aSAH patients in central China. To investigate seasonal and weekly distributions, we used the χ2 goodness-of-fit test to analyze the uniformity of the onset time. To explore monthly and circadian distributions, we established Fourier models to show the rhythmicity in chronobiological patterns. Subgroup analyses were conducted to assess the impact of age, gender, hypertension statuses, and aneurysmal characteristics (number, size, and location) on the chronobiological patterns of aSAH.

Results:

A total of 1469 patients with aSAH were recruited in the study. The seasonal and monthly distribution exhibited significantly higher incidence in winter and January/December and lower incidence in summer and July. The weekly distribution of aSAH onset showed no significant uneven variation. The circadian distribution of aSAH exhibited a significant pattern (p = 0.0145), with a morning peak around 8:00, and a late afternoon peak at 16:00–20.00. The circadian rhythmicity varied in subgroups of different ages, genders, and aneurysmal locations.

Conclusion:

The occurrence of aSAH exhibits significant circannual and circadian patterns among the Chinese population. Patients with aSAH of different ages, genders, and aneurysmal locations would present different chronobiological patterns.

Comparison of supine and seated orthostatic hypotension assessments and their association with falls and orthostatic symptoms

BACKGROUND

Orthostatic hypotension (OH) based on a change from seated-to-standing blood pressure (BP) is often used interchangeably with supine-to-standing BP.

METHODS

The Study to Understand Fall Reduction and Vitamin D in You (STURDY) was a randomized trial of vitamin D3 supplementation and fall in adults aged ≥70 years at high risk of falls. OH was defined as a drop in systolic or diastolic BP of at least 20 or 10 mmHg, measured at pre-randomization, 3-, 12-, and 24-month visits with each of 2 protocols: seated-to-standing and supine-to-standing. Participants were asked about orthostatic symptoms, and falls were ascertained via daily fall calendar, ad hoc reporting, and scheduled interviews.

RESULTS

Among 534 participants with 993 paired supine and seated assessments (mean age 76 ± 5 years, 42% women, 18% Black), mean baseline BP was 130 ± 19/68 ± 11 mmHg; 62% had a history of high BP or hypertension. Mean BP increased 3.5 (SE, 0.4)/2.6 (SE, 0.2) mmHg from sitting to standing, but decreased with supine to standing (mean change: -3.7 [SE, 0.5]/-0.8 [SE, 0.3] mmHg; P-value < 0.001). OH was detected in 2.1% (SE, 0.5) of seated versus 15.0% (SE, 1.4) of supine assessments (P < 0.001). While supine and seated OH were not associated with falls (HR: 1.55 [0.95, 2.52] vs 0.69 [0.30, 1.58]), supine systolic OH was associated with higher fall risk (HR: 1.77 [1.02, 3.05]). Supine OH was associated with self-reported fainting, blacking out, seeing spots and room spinning in the prior month (P-values < 0.03), while sitting OH was not associated with any symptoms (P-values ≥ 0.40).

CONCLUSION

Supine OH was more frequent, associated with orthostatic symptoms, and potentially more predictive of falls than seated OH.

Association of Low-Dose Triple Combination Therapy vs Usual Care With Time at Target Blood Pressure: A Secondary Analysis of the TRIUMPH Randomized Clinical Trial

Importance

Cumulative exposure to high blood pressure (BP) is an adverse prognostic marker. Assessments of BP control over time, such as time at target, have been developed but assessments of the effects of BP-lowering interventions on such measures are lacking.

Objective

To evaluate whether low-dose triple combination antihypertensive therapy was associated with greater rates of time at target compared with usual care.

Design, Setting, and Participants

The Triple Pill vs Usual Care Management for Patients With Mild-to-Moderate Hypertension (TRIUMPH) trial was a open-label randomized clinical trial of low-dose triple BP therapy vs usual care conducted in urban hospital clinics in Sri Lanka from February 2016 to May 2017. Adults with hypertension (systolic BP >140 mm Hg and/or diastolic BP >90 mm Hg or in patients with diabetes or chronic kidney disease, systolic BP >130 mm Hg and/or diastolic BP >80 mm Hg) requiring initiation (untreated patients) or escalation (patients receiving monotherapy) of antihypertensive therapy were included. Patients were excluded if they were currently taking 2 or more blood pressure-lowering drugs or had severe or uncontrolled blood pressure, accelerated hypertension or physician-determined need for slower titration of treatment, a contraindication to the triple combination pill therapy, an unstable medical condition, or clinically significant laboratory values deemed by researchers to be unsuitable for the study. All 700 individuals in the original trial were included in the secondary analysis. This post hoc analysis was conducted from December 2020 to December 2021.

Intervention

Once-daily fixed-dose triple combination pill (telmisartan 20 mg, amlodipine 2.5 mg, and chlorthalidone 12.5 mg) therapy vs usual care.

Main Outcomes and Measures

Between-group differences in time at target were compared over 24 weeks of follow-up, with time at target defined as percentage of time at target BP.

Results

There were a total of 700 randomized patients (mean [SD] age, 56 [11] years; 403 [57.6%] women). Patients allocated to the triple pill group (n = 349) had higher time at target compared with those in the usual care group (n = 351) over 24 weeks' follow-up (64% vs 43%; risk difference, 21%; 95% CI, 16-26; P < .001). Almost twice as many patients receiving triple pill therapy achieved more than 50% time at target during follow-up (64% vs 37%; P < .001). The association of the triple pill with an increase in time at target was seen early, with most patients achieving more than 50% time at target by 12 weeks. Those receiving the triple pill achieved a consistently higher time at target at all follow-up periods compared with those receiving usual care (mean [SD]: 0-6 weeks, 36.3% [30.9%] vs 21.7% [28.9%]; P < .001; 6-12 weeks, 5.2% [31.9%] vs 33.7% [33.0%]; P < .001; 12-24 weeks, 66.0% [31.1%] vs 43.5% [34.3%]; P < .001).

Conclusions and Relevance

To our knowledge, this analysis provides the first estimate of time at target as an outcome assessing longitudinal BP control in a randomized clinical trial. Among patients with mild to moderate hypertension, treatment with a low-dose triple combination pill was associated with substantially higher time at target compared with usual care.

C-reactive protein and hypertension among Ghanaian migrants and their homeland counterparts: the Research on Obesity and Diabetes among African Migrants study

BACKGROUND

Hypertension (HTN) is a growing public health problem in sub-Saharan Africa (SSA) and SSA migrants in Europe. Elevated levels of inflammatory marker C-reactive protein (CRP) have been linked to HTN but the relationship of CRP and HTN among SSA populations has not been studied. To address this knowledge gap, we studied the association between CRP and HTN in migrant and nonmigrant SSA populations residing in different settings.

METHODS

Cross-sectional data from the multicentre Research on Obesity and Diabetes among African Migrants (RODAM) study were analysed including 5683 Ghanaians aged at least 18 years, residing in rural and urban Ghana, and Europe. Multivariate logistic regression analyses were used to assess the association between high levels of CRP (≥3 mg/l) and HTN (SBP ≥140 mmHg and/or DBP ≥90 mmHg and/or use of antihypertensive medication) per geographical site and sex.

RESULTS

The association between CRP levels and HTN varied by sex and geographical location. In age-adjusted models, there was an association between high CRP levels and HTN in urban-Ghanaian women (odds ratio 1.50, 95% confidence interval 1.10-2.03), and European-Ghanaian men (1.68, 1.16-2.43) and women (1.63, 1.28-2.07). However, these associations were attenuated after adjustment for conventional risk factors, especially BMI. No association was found in rural-Ghanaians or urban-Ghanaian men.

CONCLUSION

Our findings show an association between CRP and HTN among Ghanaian migrants and urban-Ghanaian women, however, this was largely explained by conventional risk factors. Thus, prevention of conventional risk factors, in particular obesity, may help to reduce the potentially low-grade inflammatory mechanism underlying HTN.

Subjective sleep score is associated with central and peripheral blood pressure values in children aged 7-12 years

Shortened and poor-quality sleep have emerged as non-traditional risk factors for the development of hypertension in adults, and it is likely these relations extend to paediatric populations when evaluating sleep subjectively. Therefore, we aimed to evaluate subjective sleep metrics and their associations with central and peripheral blood pressure (BP) values in children. We hypothesized that poor-quality sleep and short sleep duration would be associated with elevated pressures in healthy children. Subjective sleep habits and sleep duration were evaluated using the Children's Sleep Habits Questionnaire (CSHQ) in 29 children aged 7-12 years (13 male/16 female). A total sleep score was generated by summing subscale scores: a higher score indicates poorer sleep habits. Peripheral BP was measured, and central pressures were estimated using pulse wave analysis. Pearson's r correlations were used to assess relations between total sleep score, sleep duration, and sleep score subscales with BP values. Sleep score was positively associated with central and peripheral systolic pressure (r = 0.43, p = 0.02 and r = 0.41, p = 0.03, respectively), diastolic pressure (r = 0.42, p = 0.02 and r = 0.36, p = 0.05, respectively) and mean arterial pressure (r = 0.40, p = 0.03 and r = 0.36, p = 0.03, respectively). Sleep duration was negatively associated with central and peripheral diastolic pressure (r = -0.40, p = 0.03 and r = -0.41, p = 0.03, respectively). Regarding the CSHQ subscales, daytime sleepiness and parasomnias were consistently positively associated with BP values. These findings support sleep as a primordial prevention target for hypertension and the maintenance of cardiovascular health during childhood. Consideration of a variety of sleep habits using tools such as the CSHQ may provide important insights into early-life cardiovascular risk.

Unique Associations of DNA Methylation Regions With 24-Hour Blood Pressure Phenotypes in Blacks

BACKGROUND

Epigenetic marks (eg, DNA methylation) may capture the effect of gene-environment interactions. DNA methylation is involved in blood pressure (BP) regulation and hypertension development; however, no studies have evaluated its relationship with 24-hour BP phenotypes (daytime, nighttime, and 24-hour average BPs).

METHODS

We examined the association of whole blood DNA methylation with 24-hour BP phenotypes and clinic BPs in a discovery cohort of 281 Blacks using reduced representation bisulfite sequencing. We developed a deep and region-specific methylation sequencing method, Bisulfite ULtrapLEx Targeted Sequencing and utilized it to validate our findings in a separate validation cohort (n=117).

RESULTS

Analysis of 38 215 DNA methylation regions (MRs), derived from 1 549 368 CpG sites across the genome, identified up to 72 regions that were significantly associated with 24-hour BP phenotypes. No MR was significantly associated with clinic BP. Two to 3 MRs were significantly associated with various 24-hour BP phenotypes after adjustment for age, sex, and body mass index. Together, these MRs explained up to 16.5% of the variance of 24-hour average BP, while age, sex, and BMI explained up to 11.0% of the variance. Analysis of one of the MRs in an independent cohort using Bisulfite ULtrapLEx Targeted Sequencing confirmed its association with 24-hour average BP phenotype.

CONCLUSIONS

We identified several MRs that explain a substantial portion of variances in 24-hour BP phenotypes, which might be excellent markers of cumulative effect of factors influencing 24-hour BP levels. The Bisulfite ULtrapLEx Targeted Sequencing workflow has potential to be suitable for clinical testing and population screenings on a large scale.

The Effects of Acute Exposure to Prolonged Sitting, with and Without Interruption, on Peripheral Blood Pressure Among Adults: A Systematic Review and Meta-Analysis

BACKGROUND

Previous reviews have shown that exposure to acute prolonged sitting can have detrimental effects on several cardiovascular and cardiometabolic health markers. However, to date, there has been no synthesis of peripheral blood pressure data (including systolic blood pressure, diastolic blood pressure and mean arterial pressure), an important and translatable marker of cardiovascular health. Similarly, no previous study has consolidated the effects of sitting interruptions on peripheral blood pressure.

OBJECTIVES

We aimed to (1) assess the effect of exposure to acute prolonged sitting on peripheral blood pressure and (2) determine the efficacy of sitting interruption strategies as a means of offsetting any negative effects. Subgroup analyses by age and interruption modality were performed to explore heterogeneity.

DATA SOURCES

Electronic databases (PubMed, Web of Science and, SPORTDiscus) were searched from inception to March 2021. Reference lists of eligible studies and relevant reviews were also screened.

STUDY SELECTION

Inclusion criteria for objective (1) were: (i) peripheral blood pressure was assessed non-invasively in the upper limb pre-sitting and post-sitting; (ii) studies were either randomised controlled, randomised crossover or quasi-experimental pre-test vs post-test trials; (iii) the sitting period was ≥ 1 h; (iv) pre-sitting and post-sitting measures were performed in the same posture; and (v) participants were adults (aged ≥ 18 years), free of autonomic or neuromuscular dysfunction. Additional criteria for objective (2) were: (i) the interruption strategy was during the sitting period; (ii) there was an uninterrupted sitting control condition; and (iii) the interruption strategy must have involved participants actively moving their upper or lower limbs.

APPRAISAL AND SYNTHESIS METHODS

In total, 9763 articles were identified, of which 33 met inclusion criteria for objective (1). Of those articles, 22 met inclusion criteria for objective (2). Weighted mean difference (WMD), 95% confidence intervals (95% CI), and standardised mean difference (SMD) were calculated for all trials using inverse variance heterogeneity meta-analysis modelling. Standardised mean difference was used to determine the magnitude of effect, where < 0.2, 0.2, 0.5 and 0.8 were defined as trivial, small, moderate and large, respectively.

RESULTS

(1) Prolonged uninterrupted sitting resulted in trivial and small significant increases in systolic blood pressure (WMD = 3.2 mmHg, 95% CI 0.6 to 5.8, SMD = 0.14) and mean arterial pressure (WMD = 3.3 mmHg, 95% CI 2.2 to 4.4, SMD = 0.37), respectively, and a non-significant trivial increase in diastolic blood pressure. Subgroup analyses indicated that the increases in systolic blood pressure and mean arterial pressure were more pronounced in younger age groups. (2) Interrupting bouts of prolonged sitting resulted in significantly lower systolic blood pressure (WMD =  - 4.4 mmHg, 95% CI - 7.4 to - 1.5, SMD = 0.26) and diastolic blood pressure (WMD =  - 2.4 mmHg, 95% CI - 4.5 to - 0.3, SMD = 0.19) compared with control conditions, particularly when using aerobic interruption strategies.

CONCLUSIONS

Exposure to acute prolonged uninterrupted sitting results in significant increases in systolic blood pressure and mean arterial pressure, particularly in younger age groups. Regularly interrupting bouts of prolonged sitting, particularly with aerobic interruption strategies may reduce negative effects.

Reproducibility and diurnal variation of the directional sensitivity of the cerebral pressure-flow relationship in men and women

The cerebral pressure-flow relationship has directional sensitivity, meaning the augmentation in cerebral blood flow is attenuated when mean arterial pressure (MAP) increases vs MAP decreases. We employed repeated squat-stands (RSS) to quantify it using a novel metric. However, its within-day reproducibility and the impacts of diurnal variation and biological sex are unknown. Study aims were to evaluate this metric for: 1) within-day reproducibility and diurnal variation in middle (MCA; ∆MCAv_T/∆MAP_T) and posterior cerebral arteries (PCA; ∆PCAv_T/∆MAP_T); 2) sex differences. ∆MCAv_T/∆MAP_T and ∆PCAv_T/∆MAP_T were calculated at seven time-points (08:00-17:00) in 18 participants (8 women; 24 ± 3 yrs) using the minimum-to-maximum MCAv or PCAv and MAP for each RSS at 0.05 Hz and 0.10 Hz. Relative metric values were also calculated (%MCAv_T/%MAP_T, %PCAv_T/%MAP_T). Intraclass correlation coefficient (ICC) evaluated reproducibility, which was good (0.75-0.90) to excellent (>0.90). Time-of-day impacted ∆MCAv_T/∆MAP_T (0.05 Hz: p = 0.002; 0.10 Hz: p = 0.001), %MCAv_T/%MAP_T (0.05 Hz: p = 0.035; 0.10 Hz: p = 0.009), and ∆PCAv_T/∆MAP_T (0.05 Hz: p = 0.024), albeit with small/negligible effect sizes. MAP direction impacted both arteries' metric at 0.10 Hz (all p < 0.024). Sex differences in the MCA only (p = 0.003) vanished when reported in relative terms. These findings demonstrate this metric is reproducible throughout the day in the MCA and PCA and is not impacted by biological sex.

Revisiting the neurovascular unit

The brain is supplied by an elaborate vascular network that originates extracranially and reaches deep into the brain. The concept of the neurovascular unit provides a useful framework to investigate how neuronal signals regulate nearby microvessels to support the metabolic needs of the brain, but it does not consider the role of larger cerebral arteries and systemic vasoactive signals. Furthermore, the recently emerged molecular heterogeneity of cerebrovascular cells indicates that there is no prototypical neurovascular unit replicated at all levels of the vascular network. Here, we examine the cellular and molecular diversity of the cerebrovascular tree and the relative contribution of systemic and brain-intrinsic factors to neurovascular function. Evidence supports the concept of a 'neurovascular complex' composed of segmentally diverse functional modules that implement coordinated vascular responses to central and peripheral signals to maintain homeostasis of the brain. This concept has major implications for neurovascular regulation in health and disease and for brain imaging.

Diurnal Variation of Retinal Vessel Density in Healthy Human Eyes

PRECIS

A small increase in optic nerve head vessel density (VD), but not macular VD, in the evening compared with the morning is observed in healthy subjects.

PURPOSE

To evaluate the diurnal variation of the macular and optic nerve head (ONH) VD in healthy eyes as measured with optical coherence tomography angiography (OCT-A).

METHODS

In this prospective study of healthy individuals older than 18 years old, VD parameters, including macular whole image vessel density, parafoveal vessel density, ONH whole image vessel density, ONH whole image capillary density, circumpapillary vessel density (cpVD), and circumpapillary capillary density, were measured with OCT-A at 4 time points throughout the day (8 am, 12 pm, 4 pm, and 8 pm).

RESULTS

Twenty-nine healthy eyes were included from 15 subjects (mean age: 30.9 y). After adjustment for age and mean ocular perfusion pressure, a significant positive rate of change was found for cpVD (0.05%/h; P=0.027). In contrast, macular VD changes were not significantly different. When comparing morning (8 am and 12 pm) and evening (4 pm and 8 pm) measurements, there were small, but statistically significant, increases for all ONH measurements. The greatest increase was found for cpVD (0.58%; P=0.022). Significant but small increases in mean arterial pressure and mean ocular perfusion pressure were also observed.

CONCLUSIONS

There was a small increase in ONH VD, but not macular VD, in the evening compared with the morning in healthy human eyes. As the observed difference was within the measurement variability, our results suggest the timing of OCT-A examination does not affect retinal VD measurements.

Circadian influence on post-exercise hypotension: a review

Circadian rhythm (CR) can influence the physiological and psychological parameters in every individual. There is a sinusoidal response to blood pressure brought about by the CR. A drop in blood pressure response immediately after an exercise is termed as post-exercise hypotension (PEH). The objective of the present paper is to review the influence of CR on PEH. Comparing the types of exercises, aerobic training showed a higher magnitude of the drop in PEH than resistance training. However, the majority of the studies have not considered the CR influence on PEH. With the evidence available, we can conclude that morning exercise shows the higher magnitude of the drop in PEH and could be sustained for a longer duration.

Comparison of cerebrovascular reactivity recovery following high-intensity interval training and moderate-intensity continuous training

A common inclusion criterion when assessing cerebrovascular (CVR) metrics is for individuals to abstain from exercise for 12–24 hr prior to data collections. While several studies have examined CVR during exercise, the literature describing CVR throughout post‐exercise recovery is sparse. The current investigation examined CVR measurements in nine participants (seven male) before and for 8 hr following three conditions: 45‐min moderate‐continuous exercise (at ~50% heart‐rate reserve), 25‐min high‐intensity intervals (ten, one‐minute intervals at ~85% heart‐rate reserve), and a control day (30‐min quiet rest). The hypercapnic (40–60 mmHg) and hypocapnic (25–40 mmHg) slopes were assessed via a modified rebreathing technique and controlled stepwise hyperventilation, respectively. All testing was initiated at 8:00a.m. with transcranial Doppler ultrasound measurements to index cerebral blood velocity performed prior to the condition (pre) with serial follow‐ups at zero, one, two, four, six, and eight hours within the middle and posterior cerebral artery (MCA, PCA). Absolute and relative MCA and PCA hypercapnic slopes were attenuated following high‐intensity intervals at hours zero and one (all p < .02). No alterations were observed in either hypocapnic or hypercapnic slopes following the control or moderate‐continuous exercise (all p > .13), aside from a reduced relative hypercapnic MCA slope at hours zero and one following moderate‐continuous exercise (all p < .005). The current findings indicate the common inclusion criteria of a 12–24 hr time restriction on exercise can be reduced to two hours when performing CVR measures. Furthermore, the consistent nature of the CVR indices throughout the control day indicate reproducible testing sessions can be made between 8:00a.m. and 7:00p.m.

Circadian variations in the occurrence of first-ever intracerebral hemorrhage from different sources of income: a hospital-based cross-sectional study

BACKGROUND

The onset time of intracerebral hemorrhage (ICH) may be closely related to the working style and living habits of people, which are determined by different income sources in China. Therefore, the purpose of our study was to investigate the Circadian Variations in the occurrence of ICH from different sources of income.

METHODS

This retrospective study enrolled 4,327 patients with first-ever ICH. Based on the time of day at which the patients developed symptoms, the classifiable onset time was assigned to one of eight three-hour intervals. And based on different income sources, they were categorized into three groups: Farmers, Wage-earners, and Freelancers. Demographic and risk factors of patients were then summarized, and the circadian variation of the 3 groups of patients' known time of onset and those stratified by sex and age were analyzed.

RESULTS

The frequency of ICH onset exhibited significant circadian variation among the 3 income groups, demonstrating a bimodal distribution in the daytime, with a nadir during the night (all P < 0.001). Three groups showed a significant initial peak between 06:01 and 09:00, and the same peak was observed in their subgroups of sex and age. In the 3 income source groups, there was a smaller second peak that between 15:01 and 18:00 for Farmers and Wage-earners and 18:01 and 21:00 for Freelancers. After stratification by sex and age, the second peak was between 18:01 and 21:00 for female in Farmers, female in Freelancers, under 65 years of age in Wage-earners and 65 years or older in Freelancers, while 15:01 and 18:00 for the other groups.

CONCLUSIONS

Different circadian variations of ICH onset time are found in patients with different income sources in southwest China's Chongqing Municipality cohort. Moreover, the frequency and distribution pattern of peak hours may be closely related to the working style and living habits of people with different income sources.

Effect of Sleep Disturbances on Blood Pressure

This review summarizes recent literature addressing the association of short sleep duration, shift work, and obstructive sleep apnea with hypertension risk, blood pressure (BP) levels, and 24-hour ambulatory BP. Observational studies demonstrate that subjectively assessed short sleep increases hypertension risk, though conflicting results are observed in studies of objectively assessed short sleep. Intervention studies demonstrate that mild and severe sleep restriction are associated with higher BP. Rotating and night shift work are associated with hypertension as shift work may exacerbate the detrimental impact of short sleep on BP. Further, studies demonstrate that shift work may increase nighttime BP and reduce BP control in patients with hypertension. Finally, moderate to severe obstructive sleep apnea is associated with hypertension, particularly resistant hypertension. Obstructive sleep apnea is also associated with abnormal 24-hour ambulatory BP profiles, including higher daytime and nighttime BP, nondipping BP, and a higher morning surge. Continuous positive airway pressure treatment may lower BP and improve BP dipping. In conclusion, efforts should be made to educate patients and health care providers about the importance of identifying and treating sleep disturbances for hypertension prevention and management. Empirically supported sleep health interventions represent a critical next step to advance this research area and establish causality.

Dynamic cerebral autoregulation across the cardiac cycle during 8 hr of recovery from acute exercise

Current protocols examining cerebral autoregulation (CA) parameters require participants to refrain from exercise for 12–24 hr, however there is sparse objective evidence examining the recovery trajectory of these measures following exercise across the cardiac cycle (diastole, mean, and systole). Therefore, this study sought to determine the duration acute exercise impacts CA and the within‐day reproducibility of these measures. Nine participants performed squat–stand maneuvers at 0.05 and 0.10 Hz at baseline before three interventions: 45‐min moderate‐continuous exercise (at 50% heart‐rate reserve), 30‐min high‐intensity intervals (ten, 1‐min at 85% heart‐rate reserve), and a control day (30‐min quiet rest). Squat–stands were repeated at hours zero, one, two, four, six, and eight after each condition. Transcranial doppler ultrasound of the middle cerebral artery (MCA) and the posterior cerebral artery (PCA) was used to characterize CA parameters across the cardiac cycle. At baseline, the systolic CA parameters were different than mean and diastolic components (ps < 0.015), however following both exercise protocols in both frequencies this disappeared until hour four within the MCA (ps > 0.079). In the PCA, phase values were affected only following high‐intensity intervals until hour four (ps > 0.055). Normalized gain in all cardiac cycle domains remained different following both exercise protocols (ps < 0.005) and across the control day (p < .050). All systolic differences returned by hour six across all measures (ps < 0.034). Future CA studies may use squat–stand maneuvers to assess the cerebral pressure–flow relationship 6 hr after exercise. Finally, CA measures under this paradigm appear to have negligible within‐day variation, allowing for reproducible interpretations to be drawn.

The impact of high- and moderate-intensity exercise on near-point of convergence metrics

Background: Near point of convergence (NPC) assesses the vergence ability of the visuo-oculomotor system; however, little is known regarding: the extent and duration exercise impacts NPC and the between- and within-day reliability of NPC metrics.Methods: An accommodative ruler with a miniature Snellen chart was placed upon the philtrum (upper lip). Participants (n=9) focused upon a 'V' sized 20/20, while the chart was moved at ~1-2 cm/s toward and away from the eyes (twice in each direction). Testing commenced at 8:00am with NPC measures being collected at baseline before three randomized conditions with serial follow-ups occurring at six post-condition timepoints (0-8 hours following). The conditions consisted of 25-minutes high-intensity intervals (10, one-minute intervals at ~85-90% heart-rate reserve), 45-minutes of moderate-intensity exercise (at ~50-60% heart-rate reserve), and a control condition (30-minutes quiet rest).Results: NPC was not impacted across any of the three conditions (all p > .59). Additionally, NPC measures between baseline conditions and across the control condition displayed very high levels of within-day and between-day reliability (coefficient of variation <3.8%).Conclusions: Future NPC measures using an accommodative ruler can be taken immediately following exercise and may be pertinent as a complementary tool in the future sideline screening of concussion.

Sleep disturbances: one of the culprits of obesity-related cardiovascular risk?

Growing evidence suggested that Sleep Disorders (SD) could increase the risk of developing obesity and could contribute to worsen obesity-related cardiovascular risk. Further, obesity per se has been reported to blunt sleep homeostasis. This happens through several mechanisms. First of all, the excessive adipose tissue at neck and chest levels could represent a mechanical obstacle to breathe. Moreover, the visceral adipose tissue is known to release cytokines contributing to low-grade chronic inflammation that could impair the circadian rhythm. Also, nutrition plays an important role in sleep homeostasis. High fat and/or high carbohydrate diets are known to have a negative impact on both sleep quality and duration. In addition, obesity predisposes to a condition called "obstructive sleep apnea" that has a detrimental effect on sleep. SD could increase the risk and/or could contribute to worsen cardiovascular risk usually associated with obesity. The chronic low grade inflammation associated with obesity has been reported to increase the risk of developing hypertension, type 2 diabetes and dyslipidemia. In turn, improving quality of sleep has been reported to improve the management of these cardiovascular risk factors. Thus, the aim of this manuscript is to provide evidence on the association of obesity and SD and on how they could contribute to the risk of developing cardiovascular risk factors such as hypertension, dyslipidemia and type 2 diabetes in obesity.

Comparison of diurnal variation, anatomical location, and biological sex within spontaneous and driven dynamic cerebral autoregulation measures

Presently, the literature describing the influence of diurnal variation on dynamic cerebral autoregulation (dCA) metrics is sparse. Additionally, there is little data with respect to dCA comparisons between anterior/posterior circulation beds and biological sexes using squat-stand maneuvers. Eight male and eight female participants (n = 16) performed 5 min of spontaneous upright rest and squat-stand maneuvers at 0.05 and 0.10 Hz across seven time points throughout the day. All testing sessions commenced at 8:00 a.m. each day and dCA parameters were quantified across the cardiac cycle (diastole, mean, and systole) using transcranial Doppler ultrasound to insonate cerebral blood velocity within the middle and posterior cerebral arteries (MCA, PCA). No cardiac cycle alternations were seen spontaneous (all p > .207) while a trend was noted in some driven (all p > .051) dCA metrics. Driven dCA produced much lower coefficient of variances (all <21%) compared with spontaneous (all <58%). Moreover, no sex differences were found within driven metrics (all p > .096). Between vessels, PCA absolute gain was reduced within all spontaneous and driven measures (all p < .014) whereas coherence, phase, and normalized gain were unchanged (all p > .099). There appears to be little influence of diurnal variation on dCA measures across the day (8:00 a.m. to 6:00 p.m.). Absolute gain was blunted in the PCA relative to the MCA and consistent with previous literature, driven methods demonstrated vastly improved reproducibility metrics compared to spontaneous methods. Finally, no dCA differences were found between biological sexes, demonstrating that males and females regulate in a harmonious manner, when females are tested within the early follicular phase of the menstrual cycle.

The Impact of Education and Age on Metabolic Disorders

Metabolic disorders, such as obesity, elevated blood pressure, dyslipidemias, insulin resistance, hyperglycemia, and hyperuricemia have all been identified as risk factors for an epidemic of important and widespread chronic-degenerative diseases, such as type 2 diabetes and cardiovascular disease, that constitute some of the world's most important public health challenges. Their increasing prevalence can be associated with an aging population and to lifestyles within an obesogenic environment. Taking educational level as a proxy for lifestyle, and using both logistic and linear regressions, we study the relation between a wide set of metabolic biomarkers, and educational level, body mass index (BMI), age, and sex as correlates, in a population of 1,073 students, academic and non-academic staff at Mexico's largest university (UNAM). Controlling for BMI and sex, we consider educational level and age as complementary measures-degree and duration-of exposure to metabolic insults. Analyzing the role of education across a wide spectrum of educational levels (from primary school to doctoral degree), we show that higher education correlates to significantly better metabolic health when compared to lower levels, and is associated with significantly less risk for waist circumference, systolic blood pressure, glucose, glycosylated hemoglobin, triglycerides, high density lipoprotein and metabolic syndrome (all p < 0.05); but not for diastolic blood pressure, basal insulin, uric acid, low density lipoprotein, and total cholesterol. We classify each biomarker, and corresponding metabolic disorder, by its associated set of statistically significant correlates. Differences among the sets of significant correlates indicate various aetiologies and the need for targeted population-specific interventions. Thus, variables strongly linked to educational level are candidates for lifestyle change interventions. Hence, public policy efforts should be focused on those metabolic biomarkers strongly linked to education, while adopting a different approach for those biomarkers not linked as they may be poor targets for educational campaigns.

Quantity, Quality, and Timing of Carbohydrate Intake and Blood Pressure

PURPOSE OF REVIEW

This review discusses recent evidence on the association of dietary carbohydrates (quantity, quality, and timing of intake) with hypertension (HTN) risk and out-of-clinic blood pressure (BP) measures.

RECENT FINDINGS

Studies on carbohydrate quantity are inconclusive, but low carbohydrate diets may be associated with lower BP. Plant-based carbohydrate-containing foods such as fruits, vegetables, and whole grains may lower HTN risk and 24-h BP. Excessive sugar intakes from sugar-sweetened beverages are associated with higher BP levels and HTN risk, with evidence of a dose-response relationship. Preliminary data suggest that timing of carbohydrate intake may influence HTN risk and 24-h BP. The role of carbohydrate nutrition in HTN's etiology warrants further investigation. Additional studies are needed to investigate the influence of dietary carbohydrates on HTN risk and the circadian pattern of BP, evaluate potential sex and racial/ethnic differences in these associations, and elucidate underlying mechanisms.

Sleep Duration and Blood Pressure: Recent Advances and Future Directions

PURPOSE OF REVIEW

This review discusses the recent literature on subjectively and objectively assessed sleep duration in relation to hypertension risk and out-of-clinic blood pressure (BP) measures and highlights critical areas for future research.

RECENT FINDINGS

Sleep duration, particularly short sleep, may influence BP through disturbed autonomic balance, hormonal imbalances, increased adiposity and metabolic dysfunction, and disrupted circadian rhythms. Observational studies indicate that short and long sleep are associated with hypertension risk, reduced nocturnal dipping, and elevated morning BP, but evidence is stronger for short sleep. Experimental sleep restriction increases BP, while sleep extension may lower BP in prehypertensive individuals. Women and racial/ethnic minorities are more prone to the detrimental effects of short sleep on BP. Additional studies are warranted to clarify the association of objectively assessed sleep with BP level and diurnal pattern and to determine the sex- and race-specific effects of sleep restriction and extension on BP.

Validation of the Clinical Index of Stable Febrile Neutropenia (CISNE) model in febrile neutropenia patients visiting the emergency department. Can it guide emergency physicians to a reasonable decision on outpatient vs. inpatient treatment?

Advances in oncology have enabled physicians to treat low-risk febrile neutropenia (FN) in outpatient settings. This study was aimed to explore the usefulness of the CISNE model and identify better triage in the emergency setting. This is a retrospective cohort study on 400 adult FN patients presenting to the Emergency Department of National Cancer Center, Korea from January 2010 to December 2016. All had been treated with cytotoxic chemotherapy for solid tumors in the previous 30 days. The primary outcome was the frequency of any serious complications during the duration of illness. Apparently stable patients numbered 299 (74.8%) of 400, and the remainder comprised clinically unstable patients. The stable patients fell into three cohorts according to the risk scores: CISNE I (low risk), 56 patients (18.7%); CISNE II (intermediate), 124 (41.5%) and CISNE III (high), 119 (39.8%). The primary outcome occurred in 10.7%, 19.4% and 33.6%, respectively, according to the cohort. Compared with the Multinational Association of Supportive Care in Cancer Risk Index Score (MASCC RIS), CISNE I stratum had significantly lower sensitivity (0.22 vs. 0.95 of MASCC low risk) but higher specificity (0.91 vs. 0.17) to predict zero occurrence of the primary outcome. The CISNE model was useful for identifying low-risk FN patients for outpatient treatment. The combination of the CISNE and MASCC RIS may help emergency physicians cope with FN more confidently.

Limiting feeding to the active phase reduces blood pressure without the necessity of caloric reduction or fat mass loss

Reducing body weight has been shown to lower blood pressure in obesity-related hypertension. However, success of those lifestyle interventions is limited due to poor long-term compliance. Emerging evidence indicates that feeding schedule plays a role on the regulation of blood pressure. With two studies, we examined the role of feeding schedule on energy homeostasis and blood pressure. In study 1, rats were fed a high-fat diet (HFD) ad libitum for 24 h (Control) or for 12 h during the dark phase (time-restricted feeding, TRF). In study 2, rats fed a HFD were administered a long-acting α-MSH analog at either light onset [melanotan II (MTII) light] or dark onset (MTII dark) or saline (Control). MTII light animals ate most of their calories during the active phase, similar to the TRF group. In study 1, Control and TRF rats consumed the same amount of food and gained the same amount of weight and fat mass. Interestingly, systolic and mean arterial pressure (MAP) was lower in the TRF group. In study 2, food intake was significantly lower in both MTII groups relative to Control. Although timing of injection affected light versus dark phase food consumption, neither body weight nor fat mass differed between MTII groups. Consistent with study 1, rats consuming their calories during the active phase displayed lower MAP. These data indicate that limiting feeding to the active phase reduces blood pressure without the necessity of reducing calories or fat mass, which could be relevant to obesity-related hypertension.

Repeated restraint stress produces acute and chronic changes in hemodynamic parameters in rats

Noninvasive hemodynamic measurements in rats require placing animals in restrainers. To minimize restraint stress-induced artifacts several habituation protocols have been proposed, however, the results are inconclusive. Here, we evaluated if a four-week habituation is superior to a shorter habituation, or no habituation. This is the first study comparing different habituation protocols with the use of four-week continuous telemetry measurements. We did the experiments on male, 16-week old, Sprague-Dawley rats. Continuous recordings of mean arterial blood pressure (MABP) and heart rate (HR) were made before and during habituation protocols. Rats were subjected either to control (four weeks of restraint-free recordings, n = 5) or two-week (seven restraints, n = 6) or four-week (14 restraints, n = 6) restraint sessions. The restraint protocols included placement of rats in the middle of the dark phase into plastic restrainers as used for tail-cuff measurements. Restraint lasted for 60 min, and was repeated every second day. Each restraint significantly increased MABP (by 15-25 mmHg) and HR (by 40-120 beats/min). Exposure to the restraint protocols decreased diurnal variation in MABP. There was no hemodynamic adaptation to repeated restraint, and no significant difference in hemodynamic response to restraint among controls, the two-week and the four-week groups. In conclusion, our study indicates that measurements in restrained rats are not likely being made without stress-induced changes in MABP. Moreover, in hemodynamic studies in repeatedly restrained rats longer habituation is not superior to shorter habituation.

Text Mining for Precision Medicine: Bringing Structure to EHRs and Biomedical Literature to Understand Genes and Health

The key question of precision medicine is whether it is possible to find clinically actionable granularity in diagnosing disease and classifying patient risk. The advent of next-generation sequencing and the widespread adoption of electronic health records (EHRs) have provided clinicians and researchers a wealth of data and made possible the precise characterization of individual patient genotypes and phenotypes. Unstructured text-found in biomedical publications and clinical notes-is an important component of genotype and phenotype knowledge. Publications in the biomedical literature provide essential information for interpreting genetic data. Likewise, clinical notes contain the richest source of phenotype information in EHRs. Text mining can render these texts computationally accessible and support information extraction and hypothesis generation. This chapter reviews the mechanics of text mining in precision medicine and discusses several specific use cases, including database curation for personalized cancer medicine, patient outcome prediction from EHR-derived cohorts, and pharmacogenomic research. Taken as a whole, these use cases demonstrate how text mining enables effective utilization of existing knowledge sources and thus promotes increased value for patients and healthcare systems. Text mining is an indispensable tool for translating genotype-phenotype data into effective clinical care that will undoubtedly play an important role in the eventual realization of precision medicine.

Increased protein intake is associated with uncontrolled blood pressure by 24-hour ambulatory blood pressure monitoring in patients with type 2 diabetes

OBJECTIVE

To analyze possible associations of dietary components, especially protein intake, with blood pressure (BP) during ambulatory BP monitoring (ABPM) in patients with type 2 diabetes.

METHODS

In this cross-sectional study, BP of outpatients with type 2 diabetes was evaluated by 24-hour ABPM (Spacelabs 90207) and usual diet by 3-day weighed diet records. Patients were divided into 2 groups according to their daytime ABPM: uncontrolled BP (systolic BP ≥ 135 mmHg or diastolic BP ≥ 85 mmHg) and controlled BP (systolic BP < 135 mmHg and diastolic BP < 85 mmHg). Logistic regression models unadjusted and adjusted for possible confounders (covariates) were used to analyze the association of protein and uncontrolled BP.

RESULTS

A total of 121 patients with type 2 diabetes aged 62.3 years, 54.5% of whom were women, were studied. The uncontrolled BP group had higher glycated hemoglobin (HbA1C) values (8.4 ± 2.0 vs 7.6 ± 1.3%; p = 0.04) and consumed more protein (20.0 ± 3.8 vs 18.2 ± 3.6% of energy; p = 0.01) and meat, (2.6 [1.45, 2.95] vs 2.0 [1.49, 2.90] g/kg weight; p = 0.04) than the controlled BP group. In a multivariate analysis, protein intake (% of energy) increased the chance for uncontrolled BP (odds ratio [OR] = 1.16; 95% confidence interval [CI], 1.02, 1.30; p = 0.02), adjusted for body mass index (BMI), HbA1C, low-density lipoprotein (LDL) cholesterol, number of antihypertensive medications, and ethnicity. Meat consumption higher than 3.08 g/kg weight/day more than doubled the chance for uncontrolled BP (OR = 2.53; 95% CI, 1.01, 7.60; p = 0.03).

CONCLUSION

High protein intake and meat consumption were associated with high daytime ABPM values in patients with type 2 diabetes. Reducing meat intake might represent an additional dietary intervention in hypertensive patients with type 2 diabetes.