Chronotherapy with conventional blood pressure medications improves management of hypertension and reduces cardiovascular and stroke risks

Chronotherapy involving rosiglitazone regulates the phenotypic switch of vascular smooth muscle cells by shifting the phase of TNF-α rhythm through triglyceride accumulation in macrophages

Objectives

Vascular diseases are often caused by the interaction between macrophages and vascular smooth muscle cells (VSMCs). This study aims to elucidate whether chronotherapy with rosiglitazone (RSG) can regulate the secretion rhythm of macrophages, thereby controlling the phenotypic switch of VSMCs and clarifying the potential molecular mechanisms, providing a chronotherapeutic approach for the treatment of vascular diseases.

Methods

RAW264.7 cells and A7r5 cells were synchronized via a 50 % FBS treatment. M1-type macrophages were induced through Lipopolysaccharide (LPS) exposure. Additionally, siRNA and plasmids targeting PPARγ were transfected into macrophages. The assessment encompassed cell viability, migration, inflammatory factor levels, lipid metabolites, clock gene expression, and relative protein expression.

Results

We revealed that, in alignment with core clock genes Bmal1 and CLOCK, RSG administration at ZT2 advanced the phase of TNF-α release rhythm, while ZT12 administration shifted it backward. Incubation with TNF-α at ZT2 significantly promoted the phenotype switch of VSMCs. This effect diminished when incubated at ZT12, implicating the involvement of the clock-MAPK pathway in VSMCs. Furthermore, RSG administration at ZT2 advanced the phases of PPARγ and Bmal1 genes, whereas ZT12 administration shifted them backward. Additionally, PPARγ overexpression significantly induced triglyceride (TG) accumulation in macrophages. Exogenous TG upregulated Bmal1 and CLOCK gene expression in macrophages and significantly increased TNF-α release.

Conclusion

Chronotherapy involving RSG induces TG accumulation within macrophages, resulting in alterations in circadian gene rhythms. These changes, in turn, modulate the phase of rhythmic TNF-α release and play a regulatory role in VSMCs phenotype switch. Our study establishes a theoretical foundation for chronotherapy of PPARγ agonists.

Nighttime administration of antihypertensive medication: a review of chronotherapy in hypertension

Hypertension remains a global health concern because of suboptimal blood pressure control despite advancements in antihypertensive treatments. Chronotherapy, defined as evening or bedtime administration of medication based on biological rhythms, is emerging as a potential strategy to improve blood pressure control and treatment outcomes. Clinical trials have investigated the potential effects of nighttime administration of antihypertensive medication in the improvement of 24 hours blood pressure control and reduction of cardiovascular risk. Implementing chronotherapy in clinical practice could have significant implications in enhancing blood pressure control and improving clinical outcomes in patients with hypertension, particularly those with resistant hypertension. However, recent trials have reported contradictory results, causing confusion in real-world practice. Herein we review, analyze, and critique the current evidence and propose suggestions regarding the clinical application and future directions of chronotherapy.

Population pharmacokinetics of lisinopril in hypertensive children and adolescents with normal to mildly reduced kidney function

AIMS

Lisinopril, an angiotensin-converting enzyme inhibitor, is a frequently prescribed antihypertensive drug in the paediatric population, while being used off-label under the age of 6 years in the USA and for all paediatric patients globally. The SAFEPEDRUG project (IWT-130033) investigated lisinopril pharmacokinetics in hypertensive paediatric patients corresponding with the day-to-day clinical population.

METHODS

The dose-escalation pilot study included 13 children with primary and secondary hypertension who received oral lisinopril once daily in the morning; doses ranged from 0.05 to 0.2 mg kg-1 . Patients were aged between 1.9 and 17.9 years (median 13.5 years) and weight ranged between 9.62 and 97.2 kg (median 53.2 kg). All data were analysed using Monolix version 2020R1 (Lixoft, France) and R version 3.6.2.

RESULTS

A 1-compartment model with first-order absorption and first-order elimination optimally describes the data. Parameter estimates of absorption rate constant (0.075 h-1 [0.062, 0.088], typical value [95% confidence interval]), volume of distribution (31.38 L 70 kg-1 [10.5, 52.3]) and elimination clearance (24.2 L h-1 70 kg-1 [19.5, 28.9]) show good predictive ability. Significant covariate effects include total body weight on elimination clearance, and distribution volume and estimated glomerular filtration rate (eGFR) on elimination clearance. The effects of eGFR on the elimination clearance are optimally described by a linear effect centred around 105 mL min-1  1.73 m-2 . The effects of body weight were implemented using fixed allometric exponents centred around an adult weight of 70 kg.

CONCLUSION

Lisinopril dose and regimen adjustments for paediatric patients should include eGFR on top of weight adjustments. An expanded model characterizing the pharmacodynamic effect is required to identify the optimal dose and dosing regimen.

Batteryless implantable device with built-in mechanical clock for automated and precisely timed drug administration

Adherence to medication plays a crucial role in the effective management of chronic diseases. However, patients often miss their scheduled drug administrations, resulting in suboptimal disease control. Therefore, we propose an implantable device enabled with automated and precisely timed drug administration. Our device incorporates a built-in mechanical clock movement to utilize a clockwork mechanism, i.e., a periodic turn of the hour axis, enabling automatic drug infusion at precise 12-h intervals. The actuation principle relies on the sophisticated design of the device, where the rotational movement of the hour axis is converted into potential mechanical energy and is abruptly released at the exact moment for drug administration. The clock movement can be charged either automatically by mechanical agitations or manually by winding the crown, while the device remains implanted, thereby enabling the device to be used permanently without the need for batteries. When tested using metoprolol, an antihypertensive drug, in a spontaneously hypertensive animal model, the implanted device can deliver drug automatically at precise 12-h intervals without the need for further attention, leading to similarly effective blood pressure control and ultimately, prevention of ventricular hypertrophy as compared with scheduled drug administrations. These findings suggest that our device is a promising alternative to conventional methods for complex drug administration.

Understanding circadian dynamics: current progress and future directions for chronobiology in drug discovery

INTRODUCTION

Most mammalian physiology is orchestrated by the circadian clock, including drug transport and metabolism. As a result, efficacy and toxicity of many drugs are influenced by the timing of their administration, which has led to the establishment of the field of chronopharmacology.

AREAS COVERED

In this review, the authors provide an overview of the current knowledge about the time-of-day dependent aspects of drug metabolism and the importance of chronopharmacological strategies for drug development. They also discuss the factors influencing rhythmic drug pharmacokinetic including sex, metabolic diseases, feeding rhythms, and microbiota, that are often overlooked in the context of chronopharmacology. This article summarizes the involved molecular mechanisms and functions and explains why these parameters should be considered in the process of drug discovery.

EXPERT OPINION

Although chronomodulated treatments have shown promising results, particularly for cancer, the practice is still underdeveloped due to the associated high cost and time investments. However, implementing this strategy at the preclinical stage could offer a new opportunity to translate preclinical discoveries into successful clinical treatments.

Assessment of Oxidative Stress Markers in Hypertensive Patients under the Use of Renin-Angiotensin-Aldosterone Blockers

As in other fields, chronotherapy applied to arterial hypertension (AHT) may have implications on oxidative stress. We compared the levels of some redox markers between hypertensive patients with morning and bedtime use of renin-angiotensin-aldosterone system (RAAS) blockers. This was an observational study that included patients older than 18 years with a diagnosis of essential AHT. Blood pressure (BP) figures were measured using twenty-four-hour ambulatory BP monitoring (24-h ABPM). Lipid peroxidation and protein oxidation were assessed using the thiobarbituric acid reactive substances (TBARS) and reduced thiols assays. We recruited 70 patients with a median age of 54 years, of whom 38 (54%) were women. In hypertensive patients with bedtime use of RAAS blockers, reduced thiol levels showed a positive correlation with nocturnal diastolic BP decrease. TBARS levels were associated with bedtime use of RAAS blockers in dipper and non-dipper hypertensive patients. In non-dipper patients, bedtime use of RAAS blockers was also associated with a decrease in nocturnal diastolic BP. Chronotherapy applied to bedtime use of some BP-lowering drugs in hypertensive patients may be linked to a better redox profile.

Understanding the dosing-time-dependent antihypertensive effect of valsartan and aspirin through mathematical modeling

Chronopharmacology of arterial hypertension impacts the long-term cardiovascular risk of hypertensive subjects. Therefore, clinical and computational studies have proposed optimizing antihypertensive medications' dosing time (Ta). However, the causes and mechanisms underlying the Ta-dependency antihypertensive effect have not been elucidated. Here we propose using a Ta- dependent effect model to understand and predict the antihypertensive effect of valsartan and aspirin throughout the day in subjects with grade I or II essential hypertension. The model based on physiological regulation mechanisms includes a periodic function for each parameter that changes significantly after treatment. Circadian variations of parameters depending on the dosing time allowed the determination of regulation mechanisms dependent on the circadian rhythm that were most relevant for the action of each drug. In the case of valsartan, it is the regulation of vasodilation and systemic vascular resistance. In the case of aspirin, the antithrombotic effect generates changes in the sensitivity of systemic vascular resistance and heart rate to changes in physical activity. Dosing time-dependent models predict a more significant effect on systemic vascular resistance and blood pressure when administering valsartan or aspirin at bedtime. However, circadian dependence on the regulation mechanisms showed different sensitivity of their circadian parameters and shapes of functions, presenting different phase shifts and amplitude. Therefore, different mechanisms of action and pharmacokinetic properties of each drug can generate different profiles of Ta-dependence of antihypertensive effect and optimal dosing times.

Dosing time optimization of antihypertensive medications by including the circadian rhythm in pharmacokinetic-pharmacodynamic models

Blood pressure (BP) follows a circadian variation, increasing during active hours, showing a small postprandial valley and a deeper decrease during sleep. Nighttime reduction of 10–20% relative to daytime BP is defined as a dipper pattern, and a reduction of less than 10%, as a non-dipper pattern. Despite this BP variability, hypertension’s diagnostic criteria and therapeutic objectives are usually based on BP average values. Indeed, studies have shown that chrono-pharmacological optimization significantly reduces long-term cardiovascular risk if a BP dipper pattern is maintained. Changes in the effect of antihypertensive medications can be explained by circadian variations in their pharmacokinetics (PK) and pharmacodynamics (PD). Nevertheless, BP circadian variation has been scarcely included in PK-PD models of antihypertensive medications to date. In this work, we developed PK-PD models that include circadian rhythm to find the optimal dosing time (Ta) of first-line antihypertensive medications for dipper and non-dipper patterns. The parameters of the PK-PD models were estimated using global optimization, and models were selected according to the lowest corrected Akaike information criterion value. Simultaneously, sensitivity and identifiability analysis were performed to determine the relevance of the parameters and establish those that can be estimated. Subsequently, Ta parameters were optimized to maximize the effect on BP average, BP peaks, and sleep-time dip. As a result, all selected models included at least one circadian PK component, and circadian parameters had the highest sensitivity. Furthermore, Ta with which BP>130/80 mmHg and a dip of 10–20% are achieved were proposed when possible. We show that the optimal Ta depends on the therapeutic objective, the medication, and the BP profile. Therefore, our results suggest making chrono-pharmacological recommendations in a personalized way.

New insight into ischemic stroke: Circadian rhythm in post-stroke angiogenesis

The circadian rhythm is an endogenous clock system that coordinates and optimizes various physiological and pathophysiological processes, which accord with the master and the peripheral clock. Increasing evidence indicates that endogenous circadian rhythm disruption is involved in the lesion volume and recovery of ischemic stroke. As a critical recovery mechanism in post-stroke, angiogenesis reestablishes the regional blood supply and enhances cognitive and behavioral abilities, which is mainly composed of the following processes: endothelial cell proliferation, migration, and pericyte recruitment. The available evidence revealed that the circadian governs many aspects of angiogenesis. This study reviews the mechanism by which circadian rhythms regulate the process of angiogenesis and its contribution to functional recovery in post-stroke at the aspects of the molecular level. A comprehensive understanding of the circadian clock regulating angiogenesis in post-stroke is expected to develop new strategies for the treatment of cerebral infarction.

Evidence for the Benefits of Melatonin in Cardiovascular Disease

The pineal gland is a neuroendocrine gland which produces melatonin, a neuroendocrine hormone with critical physiological roles in the circadian rhythm and sleep-wake cycle. Melatonin has been shown to possess anti-oxidant activity and neuroprotective properties. Numerous studies have shown that melatonin has significant functions in cardiovascular disease, and may have anti-aging properties. The ability of melatonin to decrease primary hypertension needs to be more extensively evaluated. Melatonin has shown significant benefits in reducing cardiac pathology, and preventing the death of cardiac muscle in response to ischemia-reperfusion in rodent species. Moreover, melatonin may also prevent the hypertrophy of the heart muscle under some circumstances, which in turn would lessen the development of heart failure. Several currently used conventional drugs show cardiotoxicity as an adverse effect. Recent rodent studies have shown that melatonin acts as an anti-oxidant and is effective in suppressing heart damage mediated by pharmacologic drugs. Therefore, melatonin has been shown to have cardioprotective activity in multiple animal and human studies. Herein, we summarize the most established benefits of melatonin in the cardiovascular system with a focus on the molecular mechanisms of action.

Role of Chrononutrition in the Antihypertensive Effects of Natural Bioactive Compounds

Hypertension (HTN) is one of the main cardiovascular risk factors and is considered a major public health problem. Numerous approaches have been developed to lower blood pressure (BP) in hypertensive patients, most of them involving pharmacological treatments. Within this context, natural bioactive compounds have emerged as a promising alternative to drugs in HTN prevention. This work reviews not only the mechanisms of BP regulation by these antihypertensive compounds, but also their efficacy depending on consumption time. Although a plethora of studies has investigated food-derived compounds, such as phenolic compounds or peptides and their impact on BP, only a few addressed the relevance of time consumption. However, it is known that BP and its main regulatory mechanisms show a 24-h oscillation. Moreover, evidence shows that phenolic compounds can interact with clock genes, which regulate the biological rhythm followed by many physiological processes. Therefore, further research might be carried out to completely elucidate the interactions along the time–nutrition–hypertension axis within the framework of chrononutrition.

Effectiveness of renal denervation in the treatment of hypertension: a literature review

BACKGROUND

Catheter-based renal denervation has been studied as a potential therapeutic option to reduce high blood pressure (BP). Preclinical studies in some experimental models have demonstrated an antihypertensive effect of renal denervation but reports from clinical trials have been mixed METHODS: We performed a literature search using combinations of the key terms 'Cardiovascular diseases, Clinical trial, Pre-clinical trials, Resistant hypertension, Renal denervation, Ablation technique, Radiofrequency ablation, Ultrasound ablation, RADIANCE SOLO, SYMPLICITY HTN, SYPRAL HTN'. The databases searched were PubMed and OVID Medline.

RESULTS

The initial SYMPLICITY HTN-1 AND HTN-2 clinical trials reported significant decreases in office BP but results from the more robustly designed SYMPLICITY HTN-3 trial, which included sham controls and ambulatory BP monitoring, showed no significant antihypertensive effect. Interest in the use of renal denervation in hypertension was once again sparked by favourable results from the SPYRAL HTN-OFF Med trial CONCLUSION: We provide a thorough, critical analysis of key preclinical and clinical studies investigating the efficacy of catheter-based renal denervation as a treatment for hypertension and highlight future areas for research to allow better translation into clinical practice.

Effect of CPAP treatment on BP in resistant hypertensive patients according to the BP dipping pattern and the presence of nocturnal hypertension

High heterogeneity in the blood pressure (BP) response to continuous positive airway pressure (CPAP) exists in patients with resistant hypertension (RH). Only nondipper normotensive and hypertensive patients exhibited BP reductions when treated with CPAP; the baseline BP dipping pattern has been proposed as a predictor of BP response to CPAP but has never been explored in patients with RH. This study aimed to assess the effect of CPAP on BP in subjects with RH with respect to BP dipping pattern or nocturnal hypertension. This is an ancillary study of the SARAH study. RH subjects with an apnea/hypopnea index (AHI) ≥ 15/h and who received CPAP treatment for 1 year were included. Subjects underwent a sleep study and ambulatory BP monitoring (ABPM) at baseline and at the 1-year follow-up. Eighty-nine RH subjects were included. The subjects were mainly male (77.5%) and obese, with a mean age of 66 years (25th-75th percentile; 59.0; 70.0) and an AHI of 32.7/h (25th-75th percentile; 25.0; 54.7). A total of 68.5% of participants were nondippers, and 71.9% had nocturnal hypertension. After 1 year of CPAP, no significant differences in ABPM parameters were observed between dippers and nondippers. According to nighttime BP, subjects with nocturnal normotension did not show significant changes in ABPM parameters, while nocturnal hypertensive subjects achieved a significant reduction in mean nighttime BP of -4.38 mmHg (-7.10 to -1.66). The adjusted difference between groups was 3.04 (-2.25 to 8.34), which was not significant. This study shows that the BP response to CPAP in patients with RH does not differ according to the BP dipping pattern (dipper and nondipper) and suggests a differential response according to the presence of nocturnal hypertension (ClinicalTrials.gov: NCT03002558).

Pharmacogenomics and circadian rhythms as mediators of cardiovascular drug-drug interactions

This article summarizes the current literature and documents new evidence concerning drug-drug interactions (DDI) stemming from pharmacogenomic and circadian rhythm determinants of therapies used to treat common cardiovascular diseases (CVD), such as atherosclerosis and hypertension. Patients with CVD often have more than one pathophysiologic condition, namely metabolic syndromes, hypertension, hyperlipidemia, and hyperglycemia, among others, which necessitate polytherapeutic or polypharmaceutic management. Interactions between drugs, drugs and food/food supplements, or drugs and genetic/epigenetic factors may have adverse impacts on the cardiovascular and other systems of the body. The mechanisms underlying cardiovascular DDI may involve the formation of a complex pharmacointeractome, including the absorption, distribution, metabolism, and elimination of drugs, which affect their respective bioavailability, efficacy, and/or harmful metabolites. The pharmacointeractome of cardiovascular drugs is likely operated with endogenous rhythms controlled by circadian clock genes. Basic and clinical investigations have improved the knowledge and understanding of cardiovascular pharmacogenomics and pharmacointeractomes, and additionally they have presented new evidence that the staging of deterministic circadian rhythms, according to the dosing time of drugs, e.g., upon awakening vs. at bedtime, cannot only differentially impact their pharmacokinetics and pharmacodynamics but also mediate agonistic/synergetic or antagonistic DDI. To properly manage CVD patients and avoid DDI, it is important that clinicians have sufficient knowledge of their multiple risk factors, i.e., age, gender, and life style elements (like diet, smoking, psychological stress, and alcohol consumption), and comorbidities, such as diabetes, hypertension, dyslipidemia, and depression, and the potential interactions between genetic or epigenetic background of their prescribed therapeutics.

Ingestion-time differences in the pharmacodynamics of dual-combination hypertension therapies: Systematic review and meta-analysis of published human trials

The pharmacodynamics of hypertension medications can be significantly affected by circadian rhythms in the biological mechanisms of the 24 h blood pressure (BP) pattern. Hypertension guidelines fail to recommend the time of day when patients, including those who require treatment with multiple medications, are to ingest BP-lowering therapy. We conducted a systematic review of published prospective trials that investigated hypertension medications for ingestion-time differences in BP-lowering, safety, patient adherence, and markers of target organ pathology. Among the search-retried 155 trials, 17 published between 1991 and 2020 totaling 1,508 hypertensive participants concerned the differential ingestion-time dependent effects of 14 unique dual-combination therapies. All but one (94.1%) of the trials, involving 98.5% of the total number of investigated individuals, reported clinically and statistically significant benefits - including enhanced reduction of asleep BP without induction of sleep-time hypotension, reduced prevalence of BP non-dipping, decreased adverse effects, improved kidney function, and reduced cardiac pathology - when dual-combination hypertension medications were ingested at-bedtime/evening rather than upon-waking/morning. A systematic and comprehensive review of the literature published in the past three decades reveals no single dual-combination hypertension trial reported significantly better benefit of the still conventional, yet unjustified by medical evidence, upon-waking/morning hypertension treatment scheme.

Long-acting tunable release of amlodipine loaded PEG-PCL micelles for tailored treatment of chronic hypertension

Hypertension is a chronic condition that requires lifelong therapeutic management. Strict adherence to drug administration timing improves efficacy, while poor adherence leads to safety concerns. In light of these challenges, we present a nanofluidic technology that enables long-acting drug delivery with tunable timing of drug administration using buried gate electrodes in nanochannels. We developed a poly(ethylene glycol) methyl ether-block-poly(ε-caprolactone) (PEG-PCL)-based micellar formulation of amlodipine besylate, a calcium channel blocker for hypertension treatment. The electrostatically charged PEG-PCL micellar formulation enhanced drug solubility and rendered amlodipine responsive to electrostatic release gating in nanochannels for sustained release at clinically relevant therapeutic dose. Using a low-power (<3 VDC) gating potential, we demonstrated tunable release of amlodipine-loaded micelles. Additionally, we showed that the released drug maintained biological activity via calcium ion blockade in vitro. This study represents a proof of concept for the potential applicability of our strategy for chronotherapeutic management of hypertension.

Once- Versus Twice-Daily Angiotensin-Converting Enzyme Inhibitors for Blood Pressure Control in Adult Patients With Hypertension

This review aimed to assess the efficacy and safety of once- versus twice-daily administration of angiotensin-converting enzyme (ACE) inhibitors for the management of hypertension. A literature search on PubMed and Google Scholar was performed (January 1980 to June 2020) using the following search terms: ACE inhibitors, lisinopril, enalapril, fosinopril, trandolapril, ramipril, perindopril, captopril, benazepril, ambulatory blood pressure, hypertension, twice-daily dosing, once-daily dosing. Reference lists from retrieved articles were examined for additional reports. Relevant English-language studies or those conducted in humans were considered. Overall, six studies were included that compared the efficacy of once-daily to twice-daily dosing of ACE inhibitors. Similar blood pressure-lowering effects, and, in some studies, greater blood pressure lowering has been noted in the twice-daily administration arm than once-daily administration of ACE inhibitors. ACE inhibitors' pharmacokinetic and pharmacodynamic properties play an integral role in determining the expected blood pressure-lowering outcome. It is noteworthy that adherence issues may arise when transitioning from a once-daily regimen to a twice-daily regimen. There appear to be no added safety concerns between twice-daily and once-daily administration of ACE inhibitors regarding safety outcomes. After reviewing the available literature, twice-daily dosing of ACE inhibitors may promote added blood pressure-lowering effects, with the advantages of reducing cost, reducing the risk of drug-drug interactions, reducing polypharmacy, and reducing patient confusion about their medications. Recommendations for twice-daily administration of ACE -inhibitors should be made via shared decision-making with the patient, and clinician judgment, to drive treatment selection.

The Effects of Renal Nerve Denervation on Blood Pressure and Target Organs in Different Hypertensive Rat Models

Background

Hypertension contributes to the progression of cardiac remodeling and renal damage. In turn, renal sympathetic hyperactivation showed elevated sympathetic nervous system activity and led to blood pressure increase in certain patients. The purpose of this study was to observe the effect of renal nerve denervation on blood pressure and target organ changes in two hypertensive rat models.

Methods

Hypertensive rats were randomly divided into a renal denervation (RDN) group and sham operation group. Wistar–Kyoto (WKY) rats of the same age were set as the baseline control group. In the secondary hypertension model, SD rats were randomly divided into five groups. Blood pressure and bodyweight were measured every week until they were euthanized.

Results

The two rat models underwent RDN at key timepoints. At these timepoints, the hearts and kidneys were collected for norepinephrine and angiotensin II measurements and histological analysis.

Conclusion

RDN performed before development of hypertension showed a significant antihypertensive effect on the secondary hypertension model.

Ingestion-time differences in the pharmacodynamics of hypertension medications: Systematic review of human chronopharmacology trials

Pharmacokinetics of hypertension medications is significantly affected by circadian rhythms that influence absorption, distribution, metabolism and elimination. Furthermore, their pharmacodynamics is affected by ingestion-time differences in kinetics and circadian rhythms comprising the biological mechanism of the 24 h blood pressure (BP) pattern. However, hypertension guidelines do not recommend the time to treat patients with medications. We conducted a systematic review of published evidence regarding ingestion-time differences of hypertension medications and their combinations on ambulatory BP-lowering, safety, and markers of target organ pathology. Some 153 trials published between 1976 and 2020, totaling 23,869 hypertensive individuals, evaluated 37 different single and 14 dual-fixed combination therapies. The vast (83.7%) majority of the trials report clinically and statistically significant benefits - including enhanced reduction of asleep BP without inducing sleep-time hypotension, reduced prevalence of the higher cardiovascular disease risk BP non-dipping 24 h profile, decreased incidence of adverse effects, improved renal function, and reduced cardiac pathology - when hypertension medications are ingested at-bedtime/evening rather than upon-waking/morning. Non-substantiated treatment-time difference in effects by the small proportion (16.3%) of published trials is likely explained by deficiencies of study design and conduct. Systematic and comprehensive review of the literature published the past 45 years reveals no single study reported significantly better benefit of the still conventional, yet unjustified by medical evidence, upon-waking/morning hypertension treatment schedule.

Comparison of the antihypertensive efficacy of morning and bedtime dosing on reducing morning blood pressure surge: A protocol for systemic review and meta-analysis

BACKGROUND

It is well known that morning blood pressure surge increases the risk of myocardial events in the first several hours post-awakening. This meta-analysis was performed to compare the antihypertensive efficacy of morning and bedtime dosing on decreasing morning blood pressure surge.

METHODS

Articles in 4 databases about clinical trials of ingestion time of antihypertensive drugs were searched and performed a meta-analysis to evaluate the different effects on morning blood pressure and absolute blood pressure (BP) reduction from baseline of between bedtime administration (experimental group) and morning awaking administration (control group).

RESULTS

The aim of this study is to compare the antihypertensive efficacy of morning and bedtime dosing on decreasing morning blood pressure surge.

CONCLUSIONS

The bedtime will provide evidence support for clinicians and patients for reducing morning blood pressure surge.

ETHICS AND DISSEMINATION

This study does not require ethical approval.

Extent of asleep blood pressure reduction by hypertension medications is ingestion-time dependent: Systematic review and meta-analysis of published human trials

Combined evidence of published prospective outcome trials and meta-analyses substantiate elevated asleep blood pressure (BP) and blunted sleep-time relative BP decline (non-dipping), regardless of wake-time office BP and awake or 24 h BP means, are jointly the most highly significant independent prognostic markers of cardiovascular disease (CVD) risk and worthy therapeutic targets for prevention. Nonetheless, current guidelines continue to recommend the diagnosis of hypertension, when based on ambulatory BP monitoring (ABPM), rely, solely, on either the 24 h or "daytime" BP means. They also fail to recommend the time to treat patients. We conducted a systematic review of published human trials regarding ingestion-time differences in the effects of hypertension medications on asleep BP and sleep-time relative BP decline. Some 62 such trials published between 1992 and 2020, totaling 6120 hypertensive persons, evaluated 21 different single and 8 dual-fixed combination therapies. The vast (82.3%) majority of the trials substantiate the bedtime/evening vs. upon-waking/morning treatment schedule produces statistically significant better clinical benefits, including enhanced reduction of asleep systolic BP by an average 5.17 mmHg (95%CI [4.04, 6.31], P < 0.001 between treatment-time groups) without inducing sleep-time hypotension, reduced prevalence of the high CVD risk non-dipper 24 h BP pattern, improved kidney function, and reduced cardiac pathology. Furthermore, systematic and comprehensive review of the ABPM-based literature published the past 29 years reveals no single study that reported significantly better benefits of the most recommended, yet unjustified by medical evidence, morning hypertension treatment-time scheme.

Guidelines for the design and conduct of human clinical trials on ingestion-time differences - chronopharmacology and chronotherapy - of hypertension medications

Current hypertension guidelines fail to provide a recommendation on when-to-treat, thus disregarding relevant circadian rhythms that regulate blood pressure (BP) level and 24 h patterning and medication pharmacokinetics and pharmacodynamics. The ideal purpose of ingestion-time (chronopharmacology, i.e. biological rhythm-dependent effects on the kinetics and dynamics of medications, and chronotherapy, i.e. the timing of pharmaceutical and other treatments to optimize efficacy and safety) trials should be to explore the potential impact of endogenous circadian rhythms on the effects of medications. Such investigations and outcome trials mandate adherence to the basic standards of human chronobiology research. In-depth review of the more than 150 human hypertension pharmacology and therapeutic trials published since 1974 that address the differential impact of upon-waking/morning versus at-bedtime/evening schedule of treatment reveals diverse protocols of sometimes suboptimal or defective design and conduct. Many have been "time-of-day," i.e. morning versus evening, rather than circadian-time-based, and some relied on wake-time office BP rather than around-the-clock ambulatory BP measurements (ABPM). Additionally, most past studies have been of too small sample size and thus statistically underpowered. As of yet, there has been no consensual agreement on the proper design, methods and conduct of such trials. This Position Statement recommends ingestion-time hypertension trials to follow minimum guidelines: (i) Recruitment of participants should be restricted to hypertensive individuals diagnosed according to ABPM diagnostic thresholds and of a comparable activity/sleep routine. (ii) Tested treatment-times should be selected according to internal biological time, expressed by the awakening and bed times of the sleep/wake cycle. (iii) ABPM should be the primary or sole method of BP assessment. (iv) The minimum-required features for analysis of the ABPM-determined 24 h BP pattern ought to be the asleep (not "nighttime") BP mean and sleep-time relative BP decline, calculated in reference to the activity/rest cycle per individual. (v) ABPM-obtained BP means should be derived by the so-called adjusted calculation procedure, not by inaccurate arithmetic averages. (vi) ABPM should be performed with validated and calibrated devices at least hourly throughout two or more consecutive 24 h periods (48 h in total) to achieve the highest reproducibility of mean wake-time, sleep-time and 48 h BP values plus the reliable classification of dipping status. (vii) Calculation of minimum required sample size in adherence with proper statistical methods must be provided. (viii) Hypertension chronopharmacology and chronotherapy trials should preferably be randomized double-blind, randomized open-label with blinded-endpoint, or crossover in design, the latter with sufficient washout period between tested treatment-time regimens.

Chronotherapy of Hypertension with Angiotensin Receptor Blockers-A Meta-Analysis of Blood Pressure Measured by Ambulatory Blood Pressure Monitoring in Randomized Trials

BACKGROUND

We performed this meta-analysis evaluating the efficacy of chronotherapy of hypertension with angiotensin receptor blockers (ARBs).

METHODS

We searched Pubmed, Web of Science, and Cochrane for all published randomized trials that compare antihypertensive effects of ARBs between bedtime dosing and awakening dosing. Blood pressure (BP) was measured by ambulatory BP monitoring in patients with mild or moderate essential hypertension.

RESULTS

The effects of ARBs on BP were assessed in 805 essential hypertensive patients included in 8 trials with a follow-up of 12 ± 3 weeks. The sleep-time systolic and diastolic BP (SBP, DBP) with bedtime dosing greatly decreased as compared with awakening dosing (weighted mean differences [WMD] for SBP WMD -5.23 [95% confidence intervals (CI), -7.27, -3.20] mm Hg, p < 0.001; WMD for DBP -2.94 [95% CI, -4.52, -1.36] mm Hg, p < 0.001). The reduction of daytime SBP (WMD 0.98 [95% CI, -0.20, 2.17] mm Hg, p = 0.10), DBP (WMD 0.11 [95% CI, -0.68, 0.89] mm Hg, p = 0.79), 24 hour SBP (WMD -0.75 [95% CI, -1.93, 0.42] mm Hg, p = 0.21) and DBP (WMD -0. 77 [95% CI, -1.55 0.01] mm Hg, p = 0.05) with bedtime dosing was similar with awakening dosing.

CONCLUSIONS

Bedtime dosing with ARBs is more effective in lowering sleep-time BP than awakening dosing in patients with essential hypertension, suggesting a utilization of chronotherapy of hypertension with ARBs to reduce sleep-time high BP. Larger multi-ethnic studies are needed to investigate the efficacy of chronotherapy of hypertension.

Update in Outpatient General Internal Medicine: Practice-Changing Evidence Published in 2019

Clinicians are challenged to stay informed of new and changing medical literature. To facilitate knowledge updates and synthesis of practice-changing information, a group of 6 internists reviewed the titles and abstracts in the 7 outpatient general internal medicine journals with the highest impact factors and relevance to outpatient internal medicine physicians: New England Journal of Medicine (NEJM), Lancet, Annals of Internal Medicine, Journal of the American Medical Association (JAMA), JAMA Internal Medicine, British Medical Journal (BMJ), and Public Library of Science (PLoS) Medicine. The following collections of article synopses and databases were also reviewed: American College of Physicians Journal Club, NEJM Journal Watch, BMJ Evidence-Based Medicine, McMaster/DynaMed Evidence Alerts, and Cochrane Reviews. A modified Delphi method was used to gain consensus based on clinical relevance to outpatient internal medicine, potential impact on practice, and strength of evidence. Article qualities and importance were debated until consensus was reached. Clusters of articles pertaining to the same topic were considered together. In total, 7 practice-changing articles were included.

Translating research evidence into clinical practice: a reminder of important clinical lessons in management of resistant hypertension through a case study in general practice

A case of a 59-year-old man with resistant hypertension, despite 8 months of non-pharmacological and pharmacological management up to maximal doses of triple antihypertensive therapy. Review of the literature found a study that reported improved blood pressure control with bedtime dosing of antihypertensive treatment. Changing to bedtime dosage of antihypertensives resulted in significant improvement in blood pressure control to below target levels. This highlights the importance of the clinicians' awareness and implementation of research findings and hence delivery of best evidence-based care.

Chronotherapy for reduction of cardiovascular risk

Numerous prospective studies establish that elevated asleep blood pressure (BP) constitutes a significant cardiovascular disease (CVD) risk factor, irrespective of daytime office BP measurements or awake and 24h BP measurements. Moreover, except for a small number of studies with flawed methodology, multiple clinical trials of high consistency document significantly better BP-lowering efficacy of hypertension medication and their combinations when ingested at bedtime compared to upon awakening as is customary. Additionally, recent trials conclude bedtime hypertension chronotherapy markedly reduces CVD risk not only in the general population, but also in more vulnerable patients of advanced age, with kidney disease, diabetes, or resistant hypertension. Collectively, these results call for a new definition of true arterial hypertension and its proper diagnosis and management.

New perspectives on the definition, diagnosis, and treatment of true arterial hypertension

INTRODUCTION

Office blood pressure measurements (OBPM), still used today for diagnosis and management of hypertension, fail to reveal clinically important features of the mostly predictable blood pressure (BP) 24 h pattern, and lead to >45% of individuals being misclassified. Current hypertension guidelines do not provide recommendation on when-to-treat, despite multiple prospective clinical trials documenting improved normalization of 24 h BP pattern and significant reduction in cardiovascular disease (CVD) events when hypertension medications are ingested at bedtime rather than upon waking.

AREAS COVERED

In this review, the authors discuss current evidence on the: (i) most relevant attributes of the 24 h BP pattern deterministic of CVD risk; (ii) asleep systolic BP (SBP) mean as the most significant therapeutic target for CVD risk reduction; (iii) ingestion-time differences in pharmacodynamics of BP-lowering medications as reported with high consistency in multiple clinical trials; and (iv) enhanced prevention of CVD events achieved by bedtime hypertension chronotherapy.

EXPERT OPINION

Several prospective trials consistently document asleep SBP mean and sleep-time relative SBP decline (dipping) constitute highly significant CVD risk factors, independent of OBPM. Bedtime, compared to customary upon-waking, hypertension chronotherapy reduces risk of major CVD events. Collectively, these findings call for new definition of true hypertension and, accordingly, its proper diagnosis and management.

Overcoming Compensatory Mechanisms toward Chronic Drug Administration to Ensure Long-Term, Sustainable Beneficial Effects

Chronic administration of drugs leads to the activation of compensatory mechanisms that may inhibit some of their activity and induce unwanted toxicity. These mechanisms are an obstacle for maintaining a sustainable effect for many chronic medications. Pathways that adapt to the burden induced by chronic drugs, whether or not related to the underlying disease, can lead to a partial or complete loss of effect. Variability characterizes many biological systems and manifests itself as large intra- and inter-individual differences in the response to drugs. Circadian rhythm-based chronotherapy is further associated with variability in responses noted among patients. This paper reviews current knowledge regarding the loss of effect of chronic medications and the range of variabilities that have been described in responses and loss of responses. Establishment of a personalized platform for overcoming these prohibitive mechanisms is presented as a model for ensuring long-term sustained medication effects. This novel platform implements personalized variability signatures and individualized circadian rhythms for preventing and opposing the prohibitive effect of the compensatory mechanisms induced by chronic drug administration.

Effect of Morning vs. Evening Turmeric Consumption on Urine Oxidative Stress Biomarkers in Obese, Middle-Aged Adults: A Feasibility Study

The circadian rhythm of biological systems is an important consideration in developing health interventions. The immune and oxidative defense systems exhibit circadian periodicity, with an anticipatory increase in activity coincident with the onset of the active period. Spice consumption is associated with enhanced oxidative defense. The objective of this study was to test the feasibility of a protocol, comparing the effects of morning vs. evening consumption of turmeric on urine markers of oxidative stress in obese, middle-aged adults. Using a within-sample design, participants received each of four clock time x treatment administrations, each separated by one week: morning turmeric; evening turmeric; morning control; evening control. Participants prepared for each lab visit by consuming a low-antioxidant diet for two days and fasting for 12 h. Urine was collected in the lab at baseline and one-hour post-meal and at home for the following five hours. The results showed that the processes were successful in executing the protocol and collecting the measurements and that participants understood and adhered to the instructions. The findings also revealed that the spice treatment did not elicit the expected antioxidant effect and that the six-hour post-treatment urine collection period did not detect differences in urine endpoints across treatments. This feasibility study revealed that modifications to the spice treatment and urine sampling timeline are needed before implementing a larger study.

On the use of actigraphy in clinical evaluation of diurnal blood pressure profile

A disturbed diurnal blood pressure profile is one of the most important risk factors of cardiovascular diseases. This review analyzes the use of simultaneous diurnal ambulatory blood pressure monitoring (ABPM) and motion activity monitoring (actigraphy) to obtain additional information for correct interpretation of ABPM results in clinically significant decision-making. The article considers practical aspects of actigraphy in expert ABPM for clock-independent calculation of the parameters of nighttime and daytime blood pressure (BP); detection of BP changes during sleep; connection with respiratory disturbances during sleep, motion activity, and body position; and sleep deprivation in shift workers. Original illustrations of simultaneous ABPM and actigraphy are provided.

Association of insulin resistance with polymorphic variants of Clock and Bmal1 genes: A case-control study

Background: Little information is available in the literature for the correlation of insulin resistance (IR) and CLOCK gene polymorphism in Chinese population. This study aimed to investigate the relationship of HOMA-IR (homeostasis model assessment of insulin resistance) to polymorphic variants of Clock and Bmal1 genes in Chinese patients with essential hypertension.Methods: A total of 334 outpatients with essential hypertension (103 patients of HOMA-IR positive and 231 patients of HOMA-IR negative) were recruited to analyze Clock T3111C and Bmal1 A1420G genotypes with DNA sequencing approach.Results: Waist circumference, body mass index, glycated hemoglobin, total cholesterol, triglyceride, and plasminogen activator inhibitor-1 were significantly increased, while high-density lipoprotein cholesterol was significantly decreased in patients with HOMA-IR positive (P < .05-0.001 vs. patients with HOMA-IR negative). Twenty-four-hour ambulatory blood pressure monitoring showed that 24-h mean systolic blood pressure (SBP), especially nightime SBP, was higher in patients with HOMA-IR positive (P < .05 vs. patients with HOMA-IR negative). Notably, compared with the negative group, the distribution frequency of C allele of Clock T3111C and GG genotype of Bmal1 A1420G were significantly higher in the HOMA-IR positive group (29.1 vs. 10.8% P < .000 and 43.7 vs. 27.7% P = .007, respectively). Logistic regression analysis showed that C allele of Clock T3111C (OR = 4.128, CI 95% 2.313-7.368, p = .000) and GG genotype of Bmal1 A1420G (OR = 1.983, CI 95% 1.117-3.521, p = .019) were independent risk factors for potential HOMA-IR in Chinese patients with essential hypertension.Conclusion: Our results indicated that Chinese hypertensive patients with C allele of Clock T3111C or GG genotype of Bmal1 A1420G might be susceptible to IR and are more likely to develop high nighttime SBP.

Total Atherosclerosis Burden of Baroreceptor-Resident Arteries Independently Predicts Blood Pressure Dipping in Patients With Ischemic Stroke

Supplemental Digital Content is available in the text.

Nighttime blood pressure (BP) generally dips by 10% to 20% of the daytime values, and abnormal BP dipping may affect vascular health independently of BP level. The regulation of BP dipping involves arterial baroreflex, whose receptors mainly reside in carotid sinuses and aortic arch. Atherosclerosis in these baroreceptor-resident arteries (BRAs) is frequent among patients with ischemic stroke (IS) and might impair their BP-regulating capacity. We aimed to examine associations between atherosclerosis of BRA and BP dipping in patients with IS. BP dipping ratio was measured by 24-hour ambulatory blood pressure monitoring on the sixth day after IS. With computed tomography angiography, atherosclerosis conditions in 10 segments of carotid sinuses and aortic arch were scored and summed as total atherosclerosis burden of BRA. Among the 245 patients with IS, 78.0% had atherosclerosis in BRA. The total AS burden of BRA was negatively correlated with systolic BP dipping ratio (r=−0.331; P<0.001) and diastolic BP dipping ratio (r=−0.225; P<0.001). After adjusting for age, sex, vascular risk factors, 24-hour BP means, cervical and intracranial atherosclerosis scores, the negative correlations still existed (adjusted β, −0.259 [95% CI, −0.416 to −0.102] and adjusted β, −0.178 [95% CI, −0.346 to −0.010], respectively). In conclusion, higher total atherosclerosis burden of BRA was independently indicative of more blunted dipping of systolic BP and diastolic BP in IS. The total atherosclerosis burden of BRA might be important for predicting and managing BP dipping in patients with IS.

Cardiovascular diseases: a therapeutic perspective around the clock

Biological rhythms are a ubiquitous feature of life. Most bodily functions, including physiological, biochemical, and behavioral processes, are coupled by the circadian rhythm. In the cardiovascular system, circadian fluctuations regulate several functions, namely heart rate, blood pressure, cardiac contractility, and metabolism. In fact, current lifestyles impose external timing constraints that clash with our internal circadian physiology, often increasing the risk of cardiovascular disease (CVD). Still, the mechanisms of dysregulation are not fully understood because this is a growing area of research. In this review, we explore the modulatory role of the circadian rhythms on cardiovascular function and disease as well as the role of chronotherapy in the context of CVD and how such an approach could improve existing therapies and assist in the development of new ones.

The Association Between Selected Molecular Biomarkers and Ambulatory Blood Pressure Patterns in African Chronic Kidney Disease and Hypertensive Patients Compared With Normotensive Controls: Protocol for a Longitudinal Study

Background

Chronic kidney disease (CKD) is a burgeoning epidemic in sub-Saharan Africa. Abnormal blood pressure variations are prevalent in CKD and potentiate the risk of cardiovascular morbidity and mortality. Certain genetic variants (angiotensin II receptor type 1 1166 A>C and angiotensin-converting enzyme insertion and deletion polymorphisms) and biomarkers such as interleukin–6, tumor necrosis factor, soluble (s) E-selectin, homocysteine, and highly sensitive C-reactive protein have been shown to affect blood pressure variability among non-African CKD, hypertensive. and nonhypertensive CKD population. However, the contributions of the pattern, genetic, and environmental determinants of ambulatory blood pressure in African CKD have not been characterized. Understanding these interactions may help to develop interventions to prevent major cardiovascular events among people with CKD.

Objective

The overarching objective of this study is to identify, document, and develop approaches to address related phenomic, genetic, and environmental determinants of ambulatory blood pressure patterns in African CKD and non-CKD hypertensive patients compared with normotensive controls.

Methods

This is a longitudinal short-term follow-up study of 200 adult subjects with CKD and 200 each of age-matched hypertensives without CKD and apparently healthy controls. Demographic information, detailed clinical profile, electrocardiography, echocardiography, and 24-hr ambulatory blood pressure measurements will be obtained. Blood samples will be collected to determine albumin-creatinine ratio, fasting plasma glucose, lipid profile, electrolytes, urea and creatinine, C-reactive protein, serum homocysteine, fibroblast growth factor–23, and complete blood count, while 2 mL blood aliquot will be collected in EDTA (ethylenediaminetetraacetic acid) tubes and mixed using an electronic rolling system to prevent blood clots and subsequently used for DNA extraction and genetic analysis.

Results

A total of 239 participants have been recruited so far, and it is expected that the recruitment phase will be complete in June 2020. The follow-up phase will continue with data analysis and publications of results.

Conclusions

This study will help stratify Nigerian CKD patients phenotypically and genotypically in terms of their blood pressure variations with implications for targeted interventions and timing of medications to improve prognosis.

International Registered Report Identifier (IRRID)

DERR1-10.2196/14820

Greater natriuretic response to ENaC inhibition in male versus female Sprague-Dawley rats

Genes for the epithelial sodium channel (ENaC) subunits are expressed in a circadian manner, but whether this results in time-of-day differences in activity is not known. Recent data show that protein expression of ENaC subunits is higher in kidneys from female rats, yet females are more efficient in excreting an acute salt load. Thus, our in vivo study determined whether there is a time-of-day difference as well as a sex difference in the response to ENaC inhibition by benzamil. Our results showed that the natriuretic and diuretic responses to a single dose of benzamil were significantly greater in male compared with female rats whether given at the beginning of the inactive period [Zeitgeber time 0 (ZT0), 7 AM] or active period (ZT12, 7 PM). However, the response to benzamil was not significantly different between ZT0 and ZT12 dosing in either male or female rats. There was no difference in renal cortical α-ENaC protein abundance between ZT0 and ZT12 or males and females. Given previous reports of flow-induced stimulation of endothelin-1 (ET-1) production and sex differences in the renal endothelin system, we measured urinary ET-1 excretion to assess the effects of increased urine flow on intrarenal ET-1. ET-1 excretion was significantly increased following benzamil administration in both sexes, but this increase was significantly greater in females. These results support the hypothesis that ENaC activity is less prominent in maintaining Na⁺ balance in females independent of renal ET-1. Because ENaC subunit genes and protein expression vary by time of day and are greater in female rat kidneys, this suggests a clear disconnect between ENaC expression and channel activity.

Asleep blood pressure: significant prognostic marker of vascular risk and therapeutic target for prevention

Aims

Sleep-time blood pressure (BP) is a stronger risk factor for cardiovascular disease (CVD) events than awake and 24 h BP means, but the potential role of asleep BP as therapeutic target for diminishing CVD risk is uncertain. We investigated whether CVD risk reduction is most associated with progressive decrease of either office or ambulatory awake or asleep BP mean.

Methods and results

We prospectively evaluated 18 078 individuals with baseline ambulatory BP ranging from normotension to hypertension. At inclusion and at scheduled visits (mainly annually) during follow-up, ambulatory BP was measured for 48 consecutive hours. During the 5.1-year median follow-up, 2311 individuals had events, including 1209 experiencing the primary outcome (composite of CVD death, myocardial infarction, coronary revascularization, heart failure, and stroke). The asleep systolic blood pressure (SBP) mean was the most significant BP-derived risk factor for the primary outcome [hazard ratio 1.29 (95% CI) 1.22-1.35 per SD elevation, P < 0.001], regardless of office [1.03 (0.97-1.09), P = 0.32], and awake SBP [1.02 (0.94-1.10), P = 0.68]. Most important, the progressive attenuation of asleep SBP was the most significant marker of event-free survival [0.75 (95% CI 0.69-0.82) per SD decrease, P < 0.001], regardless of changes in office [1.07 (0.97-1.17), P = 0.18], or awake SBP mean [0.96 (0.85-1.08), P = 0.47] during follow-up.

Conclusion

Asleep SBP is the most significant BP-derived risk factor for CVD events. Furthermore, treatment-induced decrease of asleep, but not awake SBP, a novel hypertension therapeutic target requiring periodic patient evaluation by ambulatory monitoring, is associated with significantly lower risk for CVD morbidity and mortality.

Bedtime hypertension treatment improves cardiovascular risk reduction: the Hygia Chronotherapy Trial

Aims

The Hygia Chronotherapy Trial, conducted within the clinical primary care setting, was designed to test whether bedtime in comparison to usual upon awakening hypertension therapy exerts better cardiovascular disease (CVD) risk reduction.

Methods and results

In this multicentre, controlled, prospective endpoint trial, 19 084 hypertensive patients (10 614 men/8470 women, 60.5 ± 13.7 years of age) were assigned (1:1) to ingest the entire daily dose of ≥1 hypertension medications at bedtime (n = 9552) or all of them upon awakening (n = 9532). At inclusion and at every scheduled clinic visit (at least annually) throughout follow-up, ambulatory blood pressure (ABP) monitoring was performed for 48 h. During the 6.3-year median patient follow-up, 1752 participants experienced the primary CVD outcome (CVD death, myocardial infarction, coronary revascularization, heart failure, or stroke). Patients of the bedtime, compared with the upon-waking, treatment-time regimen showed significantly lower hazard ratio—adjusted for significant influential characteristics of age, sex, type 2 diabetes, chronic kidney disease, smoking, HDL cholesterol, asleep systolic blood pressure (BP) mean, sleep-time relative systolic BP decline, and previous CVD event—of the primary CVD outcome [0.55 (95% CI 0.50–0.61), P &lt; 0.001] and each of its single components (P &lt; 0.001 in all cases), i.e. CVD death [0.44 (0.34–0.56)], myocardial infarction [0.66 (0.52–0.84)], coronary revascularization [0.60 (0.47–0.75)], heart failure [0.58 (0.49–0.70)], and stroke [0.51 (0.41–0.63)].

Conclusion

Routine ingestion by hypertensive patients of ≥1 prescribed BP-lowering medications at bedtime, as opposed to upon waking, results in improved ABP control (significantly enhanced decrease in asleep BP and increased sleep-time relative BP decline, i.e. BP dipping) and, most importantly, markedly diminished occurrence of major CVD events.

Trial registration

ClinicalTrials.gov, number NCT00741585.

 

Circadian rhythms: a possible new player in non-alcoholic fatty liver disease pathophysiology

Over the last decades, a better knowledge of the molecular machinery supervising the regulation of circadian clocks has been achieved, and numerous findings have helped in unravelling the outstanding significance of the molecular clock for the proper regulation of our physiologic and metabolic homeostasis. Non-alcoholic fatty liver disease (NAFLD) is currently considered as one of the emerging liver pathologies in the Western countries due to the modification of eating habits and lifestyle. Although NAFLD is considered a pretty benign condition, it can progress towards non-alcoholic steatohepatitis (NASH) and eventually hepatocellular carcinoma (HCC). The pathogenic mechanisms involved in NAFLD development are complex, since this disease is a multifactorial condition. Major metabolic deregulations along with a genetic background are believed to take part in this process. In this light, the aim of this review is to give a comprehensive description of how our circadian machinery is regulated and to describe to what extent our internal clock is involved in the regulation of hormonal and metabolic homeostasis, and by extension in the development and progression of NAFLD/NASH and eventually in the onset of HCC.

Race and sex differences in asleep blood pressure: The Coronary Artery Risk Development in Young Adults (CARDIA) study

Nocturnal hypertension and non-dipping blood pressure are each associated with increased risk of cardiovascular disease. We determined differences in nocturnal hypertension and non-dipping systolic/diastolic blood pressure among black and white men and women who underwent 24-hour ambulatory blood pressure monitoring at the Coronary Artery Risk Development in Young Adults study Year 30 Exam in 2015-2016. Asleep and awake periods were determined from actigraphy complemented by sleep diaries. Nocturnal hypertension was defined as mean asleep systolic/diastolic blood pressure ≥ 120/70 mm Hg. Non-dipping systolic and diastolic blood pressure, separately, were defined as a decline in awake-to-asleep blood pressure < 10%. Among 767 participants, the prevalence of nocturnal hypertension was 18.4% and 44.4% in white and black women, respectively, and 36.4% and 59.9% in white and black men, respectively. After multivariable adjustment and compared with white women, the prevalence ratio (95% confidence interval) for nocturnal hypertension was 1.65 (1.18-2.32) for black women, 1.63 (1.14-2.33) for white men, and 2.01 (1.43-2.82) for black men. The prevalence of non-dipping systolic blood pressure was 21.5% and 41.0% in white and black women, respectively, and 20.2% and 37.9% in white and black men, respectively. Compared with white women, the multivariable-adjusted prevalence ratio (95% confidence interval) for non-dipping systolic blood pressure was 1.66 (1.18-2.32), 0.91 (0.58-1.42) and 1.66 (1.15-2.39) among black women, white men, and black men, respectively. Non-dipping diastolic blood pressure did not differ by race-sex groups following multivariable adjustment. In conclusion, black women and men have a high prevalence of nocturnal hypertension and non-dipping systolic blood pressure.

Autonomic nerves and circadian control of renal function

Cardiovascular and renal physiology follow strong circadian rhythms. For instance, renal excretion of solutes and water is higher during the active period compared to the inactive period, and blood pressure peaks early in the beginning of the active period of both diurnal and nocturnal animals. The control of these rhythms is largely dependent on the expression of clock genes both in the central nervous system and within peripheral organs themselves. Although it is understood that the central and peripheral clocks interact and communicate, few studies have explored the specific mechanism by which various organ systems within the body are coordinated to control physiological processes. The renal sympathetic nervous innervation has long been known to have profound effects on renal function, and because the sympathetic nervous system follows strong circadian rhythms, it is likely that autonomic control of the kidney plays an integral role in modulating renal circadian function. This review highlights studies that provide insight into this interaction, discusses areas lacking clarity, and suggests the potential for future work to explore the role of renal autonomics in areas such as blood pressure control and chronic kidney disease.