Sleep-Time Blood Pressure: Prognostic Value and Relevance as a Therapeutic Target for Cardiovascular Risk Reduction

Blunted circadian variation of blood pressure in individuals with neurofibromatosis type 1

BACKGROUND

Cardiovascular events such as myocardial infarction and stroke are life-threatening complications associated with Neurofibromatosis type 1 (NF1). As previous studies observed an association between cardiovascular events and the loss of circadian variations of blood pressure, we investigated the 24 h circadian rhythm of blood pressure (BP) in 24 NF1 patients (10 males and 14 females, with a mean age of 39.5 years ± 14 years) by using ambulatory blood pressure monitoring (ABPM).

RESULTS

Only one-third of the patient were dippers, 50% were non-dippers, and 17% were risers. Reduced variability of systolic and diastolic nocturnal blood pressure was observed in NF1 patients compared with several studies of normotensive individuals (p = 0.024). In NF1 patients, the blunted systolic nocturnal decline was significantly associated with the number of neurofibromas (p = 0.049) and the presence of a plexiform neurofibroma (p = 0.020).

CONCLUSIONS

Most NF1 patients in this study showed a "non-dipper" pattern with a blunted nocturnal BP decline, which is considered an independent risk factor for cardiovascular events in normotensive and hypertensive individuals. Periodic monitoring of BP should be included in NF1 follow-up guidelines to diagnose masked hypertension or a non-dipper/riser pattern which would significantly increase the morbidity and mortality of NF1 patients to implement therapeutic strategies.

Effectiveness of Amlodipine in the Control of 24-Hour Blood Pressure in Mild-to-Moderate Essential Hypertension: A Prospective, Multicenter, Observational Real-World Study from India

Background Calcium-channel blockers (CCB) are a mainstay in the management of hypertension (HTN), and amlodipine is the preferred CCB due to its longer half-life and better safety. Patients and methods This practice-based, observational, real-world evidence study assessed the 24-hour ambulatory blood pressure (ABP) control in mild-to-moderate essential hypertensive patients (treatment naïve receiving amlodipine monotherapy, or as add-on therapy) in inadequately controlled blood pressure (BP goal not met after one month of existing therapy). One hundred four (62M/42F) patients between 18 and 65 years of age who received amlodipine 5/10 mg/day for >8 weeks were included after obtaining informed written consent. The primary outcome was a change from baseline in the mean 24-h SBP and DBP on ABP monitoring at eight (±1) weeks. Secondary outcomes were different from baseline in the mean morning, day-time, night-time, and last six-hour dosing interval period. Other outcomes assessed BP variability (dippers and non-dippers), and responder rates based on ABP monitoring and in-clinic trough cuff measurements. Safety outcomes included adverse effects reported, electrocardiogram, and laboratory abnormalities (hepatic and renal function). Changes in BP parameters in different sub-groups (age, gender, BMI, physical activity, occupation, duration of hypertension, the total daily dose of amlodipine, type of amlodipine therapy, and hypertension severity at baseline) were estimated. Results Of the 104 patients, 49 patients (completed eight weeks) were included in the per-protocol (PP) data for efficacy analysis. Safety analysis was done on the intent-to-treat (ITT) dataset. Significant reductions (p<0.0001) from baseline in all BP measurements on ABPM were observed at the end of eight weeks. Similar improvements were observed in office BP recordings. There was a marginal but non-significant (p>0.05) increase in the proportion of dippers and extreme dippers with amlodipine at the end of the eight-week treatment period. Conclusions Amlodipine 5/10 mg/day therapy used as monotherapy or adjuvant therapy provided significant reductions in both office BP and ambulatory BP over eight weeks.

Circadian rhythms of risk factors and management in atherosclerotic and hypertensive vascular disease: Modern chronobiological perspectives of an ancient disease

Atherosclerosis, a chronic inflammatory disease of the arteries that appears to have been as prevalent in ancient as in modern civilizations, is predisposing to life-threatening and life-ending cardiac and vascular complications, such as myocardial and cerebral infarctions. The pathogenesis of atherosclerosis involves intima plaque buildup caused by vascular endothelial dysfunction, cholesterol deposition, smooth muscle proliferation, inflammatory cell infiltration and connective tissue accumulation. Hypertension is an independent and controllable risk factor for atherosclerotic cardiovascular disease (CVD). Conversely, atherosclerosis hardens the arterial wall and raises arterial blood pressure. Many CVD patients experience both atherosclerosis and hypertension and are prescribed medications to concurrently mitigate the two disease conditions. A substantial number of publications document that many pathophysiological changes caused by atherosclerosis and hypertension occur in a manner dependent upon circadian clocks or clock gene products. This article reviews progress in the research of circadian regulation of vascular cell function, inflammation, hemostasis and atherothrombosis. In particular, it delineates the relationship of circadian organization with signal transduction and activation of the renin-angiotensin-aldosterone system as well as disturbance of the sleep/wake circadian rhythm, as exemplified by shift work, metabolic syndromes and obstructive sleep apnea (OSA), as promoters and mechanisms of atherogenesis and risk for non-fatal and fatal CVD outcomes. This article additionally updates advances in the clinical management of key biological processes of atherosclerosis to optimally achieve suppression of atherogenesis through chronotherapeutic control of atherogenic/hypertensive pathological sequelae.

Chronobiology of Exercise: Evaluating the Best Time to Exercise for Greater Cardiovascular and Metabolic Benefits

Physiological function fluctuates across 24 h due to ongoing daily patterns of behaviors and environmental changes, including the sleep/wake, rest/activity, light/dark, and daily temperature cycles. The internal circadian system prepares the body for these anticipated behavioral and environmental changes, helping to orchestrate optimal cardiovascular and metabolic responses to these daily changes. In addition, circadian disruption, caused principally by exposure to artificial light at night (e.g., as occurs with night-shift work), increases the risk for both cardiovascular and metabolic morbidity and mortality. Regular exercise is a countermeasure against cardiovascular and metabolic risk, and recent findings suggest that the cardiovascular benefits on blood pressure and autonomic control are greater with evening exercise compared to morning exercise. Moreover, exercise can also reset the timing of the circadian system, which raises the possibility that appropriate timing of exercise could be used to counteract circadian disruption. This article introduces the overall functional relevance of the human circadian system and presents the evidence surrounding the concepts that the time of day that exercise is performed can modulate the cardiovascular and metabolic benefits. Further work is needed to establish exercise as a tool to appropriately reset the circadian system following circadian misalignment to preserve cardiovascular and metabolic health. © 2022 American Physiological Society. Compr Physiol 12:3621-3639, 2022.

Bioheat Transfer Basis of Human Thermoregulation: Principles and Applications

Thermoregulation is a process that is essential to the maintenance of life for all warm-blooded mammalian and avian species. It sustains a constant core body temperature in the face of a wide array of environmental thermal conditions and intensity of physical activities that generate internal heat. A primary component of thermoregulatory function is the movement of heat between the body core and the surface via the circulation of blood. The peripheral vasculature acts as a forced convection heat exchanger between blood and local peripheral tissues throughout the body enabling heat to be convected to the skin surface where is may be transferred to and from the environment via conduction, convection, radiation, and/or evaporation of water as local conditions dictate. Humans have evolved a particular vascular structure in glabrous (hairless) skin that is especially well suited for heat exchange. These vessels are called arteriovenous anastomoses (AVAs) and can vasodilate to large diameters and accommodate high flow rates. We report herein a new technology based on a physiological principle that enables simple and safe access to the thermoregulatory control system to allow manipulation of thermoregulatory function. The technology operates by applying a small amount of heating local to control tissue on the body surface overlying the cerebral spine that upregulates AVA perfusion. Under this action, heat exchangers can be applied to glabrous skin, preferably on the palms and soles, to alter the temperature of elevated blood flow prior to its return to the core. Therapeutic and prophylactic applications are discussed.

Patient preferences for ambulatory blood pressure monitoring devices: Wrist-type or arm-type?

BACKGROUND

Ambulatory blood pressure monitoring (ABPM) is important in evaluating average 24-hour blood pressure (BP) levels, circadian rhythm, sleeping BP and BP variability but many patients are reluctant to use standard ABPM devices.

METHODS

We compared two validated ABPM devices, the BPro tonometric wrist monitor and the A&D TM-2430 oscillometric upper arm monitor, for agreement of recordings and acceptability in 37 hypertensive patients (aged 55±9 years).

RESULTS

Successful BP measurements were less frequent with the wrist-type than the arm-type device during the sleeping (66.3% vs. 92.9%, P <0.01) and awake periods (56.2% vs. 86.5%, P <0.01). Comparable paired readings showed no significant difference in systolic BP but diastolic BP (DBP) values were higher with the wrist compared to the arm monitor (24-hour 89±13 vs. 85±14 mmHg, P <0.01) with similar differences awake and sleeping. Bland-Altman analysis showed some large discrepancies between individual arm and wrist monitor measurements. More patients found the wrist monitor more comfortable to use than the arm monitor.

CONCLUSIONS

Despite the difference in individual BP measurements and the systematic overestimation of DBP values with the BPro device, wrist monitors with good patient acceptability may be useful to facilitate ABPM in some patients to provide additional information about cardiovascular risk and response to antihypertensive therapies.

Effects of insomnia and restless legs syndrome on sleep arterial blood pressure: A systematic review and meta-analysis

Hypertension and blunted blood pressure (BP) dipping during nighttime sleep are associated with increased cardiovascular risk. Chronic insomnia and restless legs syndrome (RLS) may affect the 24-h BP profile. We systematically reviewed the association of insomnia and RLS with BP values during nighttime sleep and the relative BP dipping pattern. We searched relevant articles in any language with selection criteria including enrolment of subjects with insomnia or RLS and with obstructive sleep apnea comorbidity assessment. Of the 872 studies originally retrieved, seven were selected. Four studies enrolled subjects with insomnia. One study relied on sleep diaries to classify nighttime sleep BP, whereas three relied only on clock time. At meta-analysis, subjects with insomnia displayed an attenuated dipping of systolic BP (-2.00%; 95% confidence interval (CI): -3.61 - -0.39%) and diastolic BP (-1.58%; 95% CI: -2.66 ̶ -0.49%) during nighttime sleep compared to controls. Three studies enrolled subjects with RLS. One study relied on polysomnography to classify nighttime sleep BP, whereas two relied only on clock time. Subjects with RLS showed increases in nighttime sleep systolic BP (5.61 mm Hg, 95% CI 0.13̶-11.09 mm Hg) compared to controls. In conclusion, the limited available data suggest that insomnia and RLS are both associated with altered BP control during nighttime sleep. There is need for more clinical studies to confirm these findings, specifically focusing on measurements of BP during objectively defined sleep, on causal roles of leg movements during sleep and alterations in sleep architecture, and on implications for cardiovascular risk. PROSPERO ACKNOWLEDGEMENT OF NUMBER: CRD42020217947.

Occupational lifting and risk of hypertension, stratified by use of anti-hypertensives and age - a cross-sectional and prospective cohort study

Background

Heavy occupational lifting is prevalent in the general working population and is sparsely reported to associate with hypertension, especially among older and hypertensive workers. We investigated if heavy occupational lifting is associated with hypertension and blood pressure (BP) in both cross-sectional and prospective study designs in the Copenhagen General Population Study, stratified by age, and use of anti-hypertensives.

Methods

Participation was conducted following the declaration of Helsinki and approved by the ethical committee (H-KF-01-144/01). By multivariable logistic and linear regression models, we investigated the association between heavy occupational lifting and hypertension, in a cross-sectional design (n = 67,363), using anti-hypertensives or BP ≥140/≥90 mmHg as outcome, and in a prospective design (n = 7020) with an above-median change in systolic BP (SBP) from baseline to follow-up and/or a shift from no use to use of anti-hypertensives as outcome, with and without stratification by age and use of anti-hypertensives.

Results

The odds ratio for hypertension was estimated at 0.97 (99% CI: 0.93–1.00) in the cross-sectional analysis, and at 1.08 (99% CI: 0.98–1.19) in the prospective analysis. The difference in SBP among workers with versus without heavy occupational lifting was estimated at − 0.29 mmHg (99% CI -0.82 – 0.25) in the cross-sectional and at 1.02 mmHg (99% CI -0.41 – 2.45) in the prospective analysis. No significant interaction between heavy occupational lifting and age, nor use of anti-hypertensives were shown.

Conclusions

Only the prospective analysis indicated heavy occupational lifting to increase the risk of hypertension. Further research on the association between occupational lifting and hypertension are needed.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-10651-w.

A contemporary review of obstructive sleep apnea

PURPOSE OF REVIEW

This review provides a contemporary review of sleep apnea with emphasis on definitions, epidemiology, and consequences.

RECENT FINDINGS

Amyloid β-42 is one of the main peptides forming amyloid plaques in the brains of Alzheimer patients. Poorer sleep quality and shorter sleep duration have been associated with a higher amyloid burden. Decreased sleep time in the elderly is a precipitating factor in amyloid retention. Studies have shown that the dysregulation of the homeostatic balance of the major inhibitory and excitatory amino acid neurotransmitter systems of gamma-aminobutyric acid (GABA) and glutamate play a role in sleep disordered breathing (SDB).

SUMMARY

Untreated sleep disordered breathing (obstructive sleep apnea and/or central sleep apnea) are an important cause of medical mortality and morbidity. OSA is characterized by recurrent episodes of partial or complete collapse of the upper airway during sleep followed by hypoxia and sympathetic activation. Apneic events are terminated by arousal, followed by increases in pulse and blood pressure, and re-oxygenation and the release of inflammatory factors. Individuals with OSA have an increased risk of developing atrial fibrillation. Hypoxemia and poor sleep quality because of OSA increase the risk of cognitive decline in the elderly.

From Nanowarming to Thermoregulation: New Multiscale Applications of Bioheat Transfer

This review explores bioheat transfer applications at multiple scales from nanoparticle (NP) heating to whole-body thermoregulation. For instance, iron oxide nanoparticles are being used for nanowarming, which uniformly and quickly rewarms 50-80-mL (≤5-cm-diameter) vitrified systems by coupling with radio-frequency (RF) fields where standard convective warming fails. A modification of this approach can also be used to successfully rewarm cryopreserved fish embryos (∼0.8 mm diameter) by heating previously injected gold nanoparticles with millisecond pulsed laser irradiation where standard convective warming fails. Finally, laser-induced heating of gold nanoparticles can improve the sensitivity of lateral flow assays (LFAs) so that they are competitive with laboratory tests such as the enzyme-linked immunosorbent assay. This approach addresses the main weakness of LFAs, which are otherwise the cheapest, easiest, and fastest to use point-of-care diagnostic tests in the world. Body core temperature manipulation has now become possible through selective thermal stimulation (STS) approaches. For instance, simple and safe heating of selected areas of the skin surface can open arteriovenous anastomosis flow in glabrous skin when it is not already established, thereby creating a convenient and effective pathway to induce heat flow between the body core and environment. This has led to new applications of STS to increase or decrease core temperatures in humans and animals to assist in surgery (perioperative warming), to aid ischemic stress recovery (cooling), and even to enhance the quality of sleep. Together, these multiscale applications of nanoparticle heating and thermoregulation point to dramatic opportunities for translation and impact in these prophylactic, preservative, diagnostic, and therapeutic applications of bioheat transfer.

From Nanowarming to Thermoregulation: New Multiscale Applications of Bioheat Transfer

This review explores bioheat transfer applications at multiple scales from nanoparticle (NP) heating to whole-body thermoregulation. For instance, iron oxide nanoparticles are being used for nanowarming, which uniformly and quickly rewarms 50-80-mL (≤5-cm-diameter) vitrified systems by coupling with radio-frequency (RF) fields where standard convective warming fails. A modification of this approach can also be used to successfully rewarm cryopreserved fish embryos (∼0.8 mm diameter) by heating previously injected gold nanoparticles with millisecond pulsed laser irradiation where standard convective warming fails. Finally, laser-induced heating of gold nanoparticles can improve the sensitivity of lateral flow assays (LFAs) so that they are competitive with laboratory tests such as the enzyme-linked immunosorbent assay. This approach addresses the main weakness of LFAs, which are otherwise the cheapest, easiest, and fastest to use point-of-care diagnostic tests in the world. Body core temperature manipulation has now become possible through selective thermal stimulation (STS) approaches. For instance, simple and safe heating of selected areas of the skin surface can open arteriovenous anastomosis flow in glabrous skin when it is not already established, thereby creating a convenient and effective pathway to induce heat flow between the body core and environment. This has led to new applications of STS to increase or decrease core temperatures in humans and animals to assist in surgery (perioperative warming), to aid ischemic stress recovery (cooling), and even to enhance the quality of sleep. Together, these multiscale applications of nanoparticle heating and thermoregulation point to dramatic opportunities for translation and impact in these prophylactic, preservative, diagnostic, and therapeutic applications of bioheat transfer.

Hypertension: New perspective on its definition and clinical management by bedtime therapy substantially reduces cardiovascular disease risk

Diagnosis of hypertension-elevated blood pressure (BP) associated with increased cardiovascular disease (CVD) risk-and its management for decades have been based primarily on single time-of-day office BP measurements (OBPM) assumed representative of systolic (SBP) and diastolic BP (DBP) during the entire 24-hours span. Around-the-clock ambulatory blood pressure monitoring (ABPM), however, reveals BP undergoes 24-hours patterning characterized in normotensives and uncomplicated hypertensives by striking morning-time rise, 2 daytime peaks-one ~2-3 hours after awakening and the other early evening, small midafternoon nadir and 10-20% decline (BP dipping) in the asleep BP mean relative to the wake-time BP mean. A growing number of outcome trials substantiate correlation between BP and target organ damage, vascular and other risks is greater for the ABPM-derived asleep BP mean, independent and stronger predictor of CVD risk, than daytime OBPM or ABPM-derived awake BP. Additionally, bedtime hypertension chronotherapy, that is, ingestion of ≥1 conventional hypertension medications at bedtime to achieve efficient attenuation of asleep BP, better reduces total CVD events by 61% and major events (CVD death, myocardial infarction, ischaemic and haemorrhagic stroke) by 67%-even in more vulnerable chronic kidney disease, diabetes and resistant hypertension patients-than customary on-awaking therapy that targets wake-time BP. Such findings of around-the-clock ABPM and bedtime hypertension outcome trials, consistently indicating greater importance of asleep BP than daytime OBPM or ambulatory awake BP, call for a new definition of true arterial hypertension plus modern approaches for its diagnosis and management.

The Effect of Occupational Lifting on Hypertension Risk: Protocol for a Project Using Data From the Copenhagen City Heart Study

BACKGROUND

Hypertension is a major risk factor for cardiovascular disease and is responsible for 14% of all annual deaths globally. The prevalence of hypertension varies across occupational groups, possibly affected by differences in the working environment. One work-related factor that might impose a risk for hypertension is lifting due to the acute large increases in blood pressure (BP) during lifting.

OBJECTIVE

The aim of this study is to explore associations between heavy occupational lifting and hypertension in the Copenhagen City Heart Study.

METHODS

This study will use data from the third, fourth, and fifth examination of the Copenhagen City Heart Study. The dataset contains person-based information on health as well as a large variety of biological, environmental, and lifestyle-related factors. Using a cross-sectional design, we will investigate the association between heavy occupational lifting and hypertension, defined as using antihypertensive drugs or having a measured systolic BP (SBP) ≥140 mm Hg or diastolic BP (DBP) ≥90 mm Hg. Furthermore, in a prospective design, we will investigate the association between heavy occupational lifting and risk of becoming an SBP case, defined as the shift from not using antihypertensive drugs in examination n to use of antihypertensive drugs in examination n+1 or an above median delta value of SBP (SBP in examination n+1−SBP in examination n).

RESULTS

In the third examination in 1991-1994, 10,135 out of 16,560 participants attended (61.20%), in the fourth examination in 2001-2003, 6237 out of 12,599 participants attended (49.50%), and in the fifth examination in 2011-2015, 4550 out of 9765 participants attended (46.59%). On the basis of the inclusion criteria of answering to the level of occupational physical activity, 5031 observations were excluded from examination 3, 2600 from examination 4, and 1621 from examination 5. Hence, the final populations for the cross-sectional and prospective analysis are assumed to include less than 7166 participants in the cross-sectional analysis and less than 1850 participants in the prospective analysis due to the additional inclusion criteria of measured BP and use of antihypertensive drugs.

CONCLUSIONS

One-third of the workforce in Europe reports to carry or move heavy loads regularly during working hours (6th survey in Eurofound). Thus, if this study shows occupational lifting to increase the risk for hypertension, the prevention for hypertension can be improved.

Effect of the physical activity program on the treatment of resistant hypertension in primary care

BACKGROUND

Regular physical activity is widely recommended for patients with arterial hypertension as an essential component of lifestyle modification. Much less is known about the impact of physical exercise on the management of treatment of resistant hypertension (RH). The aim was to assess the effect of physical activity program intensified by mobile phone text reminders on blood pressure control in subjects with RH managed in the primary care.

METHODS

In total, 53 patients with primary hypertension were qualified, including 27 who met the criteria for RH and 26 with well-controlled hypertension (WCH). Ambulatory 24-h blood pressure was monitored and body composition evaluated with bioimpedance and habitual physical activity profile was determined continuously over 72 h with accelerometer. All measurements were performed at baseline and after three and six months. The patients were asked to modify their lifestyle according to American Heart Association Guidelines that included regular aerobic physical activity tailored to individual needs.FindingsPhysical activity in RH increased significantly after six months compared with control subjects (P=0.001). Office systolic blood pressure (SBP) and diastolic blood pressure (DBP) in the RH group decreased significantly after three months but after six months only office DBP remained significantly lower. After three months 24-h SBP decreased by 3.1±11 mmHg (P=0.08) and DBP by 2.0±6 mmHg (P=0.17) in RH, whereas in WCH respective changes were +1.2±10 and -0.3±6 mmHg. After six months 24-h BP changes were similar.

CONCLUSION

Individualized structured physical activity program increases physical activity in the treatment of resistant hypertensives in primary care but the effect on 24-h blood pressure is only transient.

Cardiovascular effects of oral appliance therapy in obstructive sleep apnea: A systematic review and meta-analysis

Obstructive sleep apnea (OSA) is associated with increased cardiovascular morbidity and mortality. This study systematically reviews the effects of oral appliance therapy (OAT) on a broad spectrum of cardiovascular outcomes. A literature search was performed up to December 31st 2016. Twenty-five relevant full-text articles were retrieved. Sixteen articles were considered methodologically sufficient, including 11 randomized controlled trials. Pooled data of the RCTs showed significant reductions in daytime systolic and diastolic blood pressure compared to baseline, but no significant reductions in heart rate, except for daytime heart rate when compared to inactive/placebo OAT. OAT and continuous positive airway pressure (CPAP) were equally effective in reducing blood pressure. Studies assessing the effect of OAT on heart rate variability, circulating cardiovascular biomarkers, and endothelial function and arterial stiffness, generally involved small numbers of patients, and were heterogeneous and inconclusive. Studies assessing the effect of OAT on cardiac function showed no effects on echocardiographic outcomes. One observational study showed that OAT was as effective as CPAP in reducing cardiovascular death. It could be speculated that OAT may lead to a reduction in long-term cardiovascular morbidity and mortality in OSA patients. However, further methodologically high quality, longitudinal studies are warranted to address this key question.

Do night and around-the-clock firefighters' shift schedules induce deviation in tau from 24 hours of systolic and diastolic blood pressure circadian rhythms?

Systolic (S) and diastolic (D) blood pressures (BP) [SBP and DBP] are circadian rhythmic with period (τ) in healthy persons assumed to be maintained at 24.0h. We tested this assumption in a sample of 30 healthy career (mean >12 yrs) 30-to-46 yr-old male Caucasian French firefighters (FFs) categorized into three groups according to work schedule and duties: Group A - 12 FFs working 12h day, 12h night, and occasionally 24h shifts and whose primary duties are firefighting plus paramedical and road rescue services; Group B - 9 FFs working mostly 12h day and 12h night shifts and whose duties are answering incoming emergency calls and coordinating service vehicle dispatch from fire stations with Group A personnel; Group C - 9 day shift (09:00-17:00h) FFs charged with administrative tasks. SBP and DBP, both in winter and in summer studies of the same FFs, were sampled by ambulatory BP monitoring every 1h between 06:00-23:00h and every 2h between 23:01-05:59h, respectively, their approximate off-duty wake and sleep spans, for 7 consecutive days. Activity (wrist actigraphy) was also sampled at 1-min intervals. Prominent τ of each variable was derived by a power spectrum program written for unequal-interval time series data, and between-group differences in incidence of τ≠24h of FFs were assessed by chi square test. Circadian rhythm disruption (τ≠24h) of either the SBP or DBP rhythm occurred almost exclusively in night and 24h shift FFs of Group A and B, but almost never in day shift FFs of Group C, and it was not associated with altered τ from 24.0h of the circadian activity rhythm. In summer, occurrence of τ≠24 for FFs of Group A and B differed from that for FFs of Group C in SBP (p=0.042) and DBP (p=0.015); no such differences were found in winter (p>0.10). Overall, manifestation of prominent τ≠24h of SBP or DBP time series was greater in summer than winter, 27.6% versus 16.7%, when workload of Group B FFs, i.e. number of incoming emergency telephone calls, and of Group A FFs, i.e. number of dispatches for provision of emergency services, was, respectively, two and fourfold greater and number of 12h night shifts worked by Group B FFs and number of 24h shifts worked by Group A FFs was, respectively, 92% and 25% greater. FFs of the three groups exhibited no winter-summer difference in τ≠24h of SBP or SDP; however, τ≠24h of DBP in Group B FFs was more frequent in summer than winter (p=0.046). Sleep/wake cycle disruption, sleep deprivation, emotional and physical stress, artificial light-at-night, and altered nutrient timings are hypothesized causes of τ≠24h for BP rhythms of affected Groups A and B FFs, but with unknown future health effects.

Sleep-Time Ambulatory BP Is an Independent Prognostic Marker of CKD

The prognostic value of clinic and ambulatory BP in predicting incident CKD and whether CKD risk reduction associates with progressive treatment-induced decrease of clinic, awake, or asleep BP are unknown. We prospectively evaluated 2763 individuals without CKD, 1343 men and 1420 women (mean±SD age: 51.5±14.3 years old), with baseline ambulatory BP ranging from normotension to hypertension. On recruitment and annually thereafter (more frequently if hypertension treatment was adjusted on the basis of ambulatory BP), we simultaneously monitored BP and physical activity (wrist actigraphy) for 48 hours to accurately derive individualized mean awake and asleep BP. During a median 5.9-year follow-up, 404 participants developed CKD. Mean asleep systolic BP was the most significant predictor of CKD in a Cox proportional hazard model adjusted for age, diabetes, serum creatinine concentration, urinary albumin concentration, previous cardiovascular event, and hypertension treatment time (on awakening versus at bedtime; per 1-SD elevation: hazard ratio, 1.44; 95% confidence interval, 1.31 to 1.56; P<0.001). The predictive values of mean clinic BP and mean awake or 48-hour ambulatory BP was not significant when corrected by mean asleep BP. Analyses of BP changes during follow-up revealed 27% reduction in the risk of CKD per 1-SD decrease in mean asleep systolic BP, independent of changes in mean clinic BP or awake ambulatory BP. In conclusion, sleep-time BP is a highly significant independent prognostic marker for CKD. Furthermore, progressive treatment-induced decrease of asleep BP, a potential therapeutic target requiring ambulatory BP evaluation, might be a significant method for reducing CKD risk.

Bedtime Blood Pressure Chronotherapy Significantly Improves Hypertension Management

Consistent evidence of numerous studies substantiates the asleep blood pressure (BP) mean derived from ambulatory BP monitoring (ABPM) is both an independent and a stronger predictor of cardiovascular disease (CVD) risk than are daytime clinic BP measurements or the ABPM-determined awake or 24-hour BP means. Hence, cost-effective adequate control of sleep-time BP is of marked clinical relevance. Ingestion time, according to circadian rhythms, of hypertension medications of 6 different classes and their combinations significantly improves BP control, particularly sleep-time BP, and reduces adverse effects.

Bedtime Chronotherapy with Conventional Hypertension Medications to Target Increased Asleep Blood Pressure Results in Markedly Better Chronoprevention of Cardiovascular and Other Risks than Customary On-awakening Therapy

The bases for bedtime hypertension chronotherapy (BHCT) as superior chronoprevention against cardiovascular disease (CVD) are: (1) correlation between blood pressure (BP) and various risks is greater for ambulatory BP monitoring (ABPM) than office BP measurements (OBPM); (2) asleep BP mean is a better predictor of CVD risk than ABPM awake and 24-hour means and OBPM; and (3) targeting of asleep BP by BHCT with one or more conventional medications versus usual on-awakening therapy better reduces major and total CVD events. BHCT offers the most cost-effective chronoprevention against adverse CVD outcomes in regular and vulnerable renal, diabetic, and resistant hypertensive patients.

Circadian disruption: New clinical perspective of disease pathology and basis for chronotherapeutic intervention

Biological processes are organized in time as innate rhythms defined by the period (τ), phase (peak [Φ] and trough time), amplitude (A, peak-trough difference) and mean level. The human time structure in its entirety is comprised of ultradian (τ < 20 h), circadian (20 h > τ < 28 h) and infradian (τ > 28 h) bioperiodicities. The circadian time structure (CTS) of human beings, which is more complicated than in lower animals, is orchestrated and staged by a brain central multioscillator system that includes a prominent pacemaker - the suprachiasmatic nuclei of the hypothalamus. Additional pacemaker activities are provided by the pineal hormone melatonin, which circulates during the nighttime, and the left and right cerebral cortices. Under ordinary circumstances this system coordinates the τ and Φ of rhythms driven by subservient peripheral cell, tissue and organ clock networks. Cyclic environmental, feeding and social time cues synchronize the endogenous 24 h clocks and rhythms. Accordingly, processes and functions of the internal environment are integrated in time for maximum biological efficiency, and they are also organized and synchronized in time to the external environment to ensure optimal performance and response to challenge. Artificial light at night (ALAN) exposure can alter the CTS as can night work, which, like rapid transmeridian displacement by air travel, necessitates realignment of the Φ of the multitude of 24 h rhythms. In 2001, Stevens and Rea coined the phrase "circadian disruption" (CD) to label the CTS misalignment induced by ALAN and shift work (SW) as a potential pathologic mechanism of the increased risk for cancer and other medical conditions. Current concerns relating to the effects of ALAN exposure on the CTS motivated us to renew our long-standing interest in the possible role of CD in the etiopathology of common human diseases and patient care. A surprisingly large number of medical conditions involve CD: adrenal insufficiency; nocturia; sleep-time non-dipping and rising blood pressure 24 h patterns (nocturnal hypertension); delayed sleep phase syndrome, non-24 h sleep/wake disorder; recurrent hypersomnia; SW intolerance; delirium; peptic ulcer disease; kidney failure; depression; mania; bipolar disorder; Parkinson's disease; Smith-Magenis syndrome; fatal familial insomnia syndrome; autism spectrum disorder; asthma; byssinosis; cancers; hand, foot and mouth disease; post-operative state; and ICU outcome. Poorly conceived medical interventions, for example nighttime dosing of synthetic corticosteroids and certain β-antagonists and cyclic nocturnal enteral or parenteral nutrition, plus lifestyle habits, including atypical eating times and chronic alcohol consumption, also can be causal of CD. Just as surprisingly are the many proven chronotherapeutic strategies available today to manage the CD of several of these medical conditions. In clinical medicine, CD seems to be a common, yet mostly unrecognized, pathologic mechanism of human disease as are the many effective chronotherapeutic interventions to remedy it.

Sleep-time ambulatory blood pressure as a prognostic marker of vascular and other risks and therapeutic target for prevention by hypertension chronotherapy: Rationale and design of the Hygia Project

This article describes the rationale, objectives, design and conduct of the ambulatory blood pressure monitoring (ABPM)-based Hygia Project. Given the substantial evidence of the significantly better prognostic value of ABPM compared to clinic BP measurements, several international guidelines now propose ABPM as a requirement to confirm the office diagnosis of hypertension. Nonetheless, all previous ABPM outcome investigations, except the Monitorización Ambulatoria para Predicción de Eventos Cardiovasculares study (MAPEC) study, relied upon only a single, low-reproducible 24 h ABPM assessment per participant done at study inclusion, thus precluding the opportunity to explore the potential reduction in cardiovascular disease (CVD) risk associated with modification of prognostic ABPM-derived parameters by hypertension therapy. The findings of the single-center MAPEC study, based upon periodic systematic 48 h ABPM evaluation of all participants during a median follow-up of 5.6 years, constitute the first proof-of-concept evidence that the progressive reduction of the asleep systolic blood pressure (SBP) mean and correction of the sleep-time relative SBP decline toward the normal dipper BP profile, most efficiently accomplished by a bedtime hypertension treatment strategy, best attenuates the risk of CVD, stroke and development of new-onset diabetes. The Hygia Project, primarily designed to extend the use of ABPM in primary care as a requirement for diagnosis of hypertension, evaluation of response to treatment and individualized assessment of CVD and other risks, is a research network presently composed of 40 clinical sites and 292 investigators. Its main objectives are to (i) investigate whether specific treatment-induced changes in ABPM-derived parameters reduce risk of CVD events, stroke, new-onset diabetes and/or development of chronic kidney disease (CKD); and (ii) test the hypothesis that bedtime chronotherapy entailing the entire daily dose of ≥1 conventional hypertension medications exerts better ambulatory BP control and CVD, metabolic and renal risk reduction than all such medications ingested in the morning upon awakening. Between 2007 and 2015, investigators recruited 18 078 persons [9769 men/8309 women, 59.1 ± 14.3 years of age (mean ± SD)], including 15 764 with hypertension according to ABPM criteria as participants in the prospective randomized chronotherapy trial. The initial evaluation includes 48 h ABPM, detailed medical history and screening laboratory blood and urine tests. The same evaluation procedure is scheduled annually, or more frequently when treatment adjustment is required for proper ambulatory BP control, targeting a median follow-up of >5 years. The primary CVD outcome end point is the composite of CVD death, myocardial infarction, coronary revascularization, heart failure, ischemic stroke and hemorrhagic stroke. The independent Hygia Project Events Committee periodically evaluates blinded clinical reports to ascertain and certify every documented event. Beyond the potential findings resulting from testing the main hypotheses, the Hygia Project has already demonstrated, as proof of concept, that the routine diagnosis of hypertension and individualized assessment of CVD and other risks by ABPM, as currently recommended, is fully viable in the primary care setting, where most people with either hypertension, dyslipidemia, type 2 diabetes or CKD receive routine medical attention.

Bedtime ingestion of hypertension medications reduces the risk of new-onset type 2 diabetes: a randomised controlled trial

AIMS/HYPOTHESIS

We investigated whether therapy with the entire daily dose of ≥ 1 hypertension medications at bedtime exerts greater reduction in the risk of new-onset diabetes than therapy with all medications upon awakening.

METHODS

We conducted a prospective, randomised, open-label, blinded endpoint trial of 2,012 hypertensive patients without diabetes, 976 men and 1,036 women, 52.7 ± 13.6 years of age. Patients were randomised, using a computer-generated allocation table, to ingest all their prescribed hypertension medications upon awakening or the entire daily dose of ≥ 1 of them at bedtime. Investigators blinded to the hypertension treatment scheme of the patients assessed the development of new-onset diabetes.

RESULTS

During a 5.9-year median follow-up, 171 participants developed type 2 diabetes. Patients of the bedtime, compared with the morning-treatment group, showed: (1) significantly lower asleep BP mean, greater sleep-time relative BP decline and attenuated prevalence of non-dipping at the final evaluation (32% vs 52%, p < 0.001); and (2) significantly lower HR of new-onset diabetes after adjustment for the significant influential characteristics of fasting glucose, waist circumference, asleep systolic BP mean, dipping classification and chronic kidney disease (CKD) (unadjusted HR 0.41 [95% CI 0.29, 0.58]; adjusted HR 0.43 [0.31, 0.61]; event-rate 4.8% vs 12.1% with bedtime and morning treatment, respectively; p < 0.001). Greater benefit was observed for bedtime compared with awakening treatment with angiotensin receptor blockers (ARBs) (HR 0.39 [0.22, 0.69]; p < 0.001), ACE inhibitors (0.31 [0.12, 0.79], p = 0.015) and β-blockers (0.35 [0.14, 0.85], p = 0.021).

CONCLUSIONS/INTERPRETATION

In hypertensive patients without diabetes, ingestion of ≥ 1 BP-lowering medications at bedtime, mainly those modulating or blocking the effects of angiotensin II, compared with ingestion of all such medications upon awakening, results in improved ambulatory BP (ABP) control (significant further decrease of asleep BP) and reduced risk of new-onset diabetes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00295542.

FUNDING

This independent investigator-promoted research was supported by unrestricted grants from Ministerio de Ciencia e Innovación (SAF2006-6254-FEDER; SAF2009-7028-FEDER); Xunta de Galicia (PGIDIT03-PXIB-32201PR; INCITE07-PXI-322003ES; INCITE08-E1R-322063ES; INCITE09-E2R-322099ES; 09CSA018322PR); and Vicerrectorado de Investigación, University of Vigo.

Sleep-time BP: prognostic marker of type 2 diabetes and therapeutic target for prevention

AIMS/HYPOTHESIS

We investigated the prognostic value of clinic and ambulatory BP (ABP) to predict new-onset diabetes and whether risk reduction is related to the progressive decrease of clinic BP or awake or asleep ABP.

METHODS

We prospectively evaluated 2,656 individuals without diabetes, 1,292 men and 1,364 women, 50.6 ± 14.3 years of age, with baseline BP ranging from normotension to hypertension according to ABP criteria. At baseline and annually (more frequently if hypertension treatment was adjusted based on ABP) thereafter, ABP and physical activity (wrist actigraphy) were simultaneously monitored for 48 h to accurately derive the awake and asleep BP means.

RESULTS

During a 5.9-year median follow-up, 190 participants developed type 2 diabetes. The asleep systolic ABP mean was the most significant predictor of new-onset diabetes in a Cox proportional-hazard model adjusted for age, waist circumference, glucose, chronic kidney disease (CKD) and hypertension treatment. Daytime clinic BP and awake or 48 h ABP mean had no predictive value when corrected by the asleep ABP mean. Analyses of BP changes during follow-up revealed a 30% reduction in the risk of new-onset diabetes per 1-SD decrease in asleep systolic ABP mean, independent of changes in clinic BP or awake or 48 h ABP means.

CONCLUSIONS/INTERPRETATION

Sleep-time BP is a highly significant independent prognostic marker for new-onset diabetes. Alteration in sleep-time BP regulation seems to precede, rather than follow, the development of new-onset diabetes. Most important, lowering asleep BP, a novel therapeutic target requiring ABP evaluation, could be a significant method for reducing new-onset diabetes risk.

Nocturnal and Circadian Rhythm of Blood Pressure Is Associated with Renal Structure Damage and Function in Patients with IgAN

BACKGROUND AND AIMS

Abnormal circadian rhythm of blood pressure (BP) is closely related to target organ damage in hypertension. However, the association between abnormal circadian rhythm of BP and renal injury is not clear. We investigated whether renal injury is associated with nocturnal BP and circadian rhythm of BP in Chinese IgAN patients.

METHODS

Clinic and 24 h ambulatory BP monitoring data were obtained from 330 Chinese IgAN patients with mean 24 h BP < 130/80 and mean daytime BP < 135/85 mmHg. Renal histopathological injury was determined according to the Oxford classification of IgAN.

RESULTS

Among the 330 IgAN subjects, 35.8% suffered from nocturnal hypertension, 61.5% had abnormal circadian BP, and 27% had nocturnal hypertension with a nondipping pattern. Compared with nocturnal normotensive patients, patients with nocturnal hypertension had significantly higher levels of blood cystatin C, blood uric acid, and lower estimated glomerular filtration rate (eGFR), and significantly a higher mean renal tissue injury score. The nondipping hypertensive group had significantly higher nocturnal diastolic and systolic BP, blood uric acid, and glomerulosclerosis rates, whereas eGFR was lower. In nondipping hypertensive patients, urinary sodium excretion and renal tissue injury scores were significantly higher than dipping patients. Nocturnal hypertension and abnormal circadian BP correlated with renal tissue injury, renal interstitial fibrosis, and aortic arch atherosclerosis.

CONCLUSION

Abnormal circadian rhythm of BP and nocturnal hypertension are common clinical manifestations in Chinese IgAN patients with normal mean 24 h BP. Abnormal circadian BP and nocturnal hypertension may accelerate IgAN progression by inducing renal dysfunction and histopathological damage.

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

Correlation between blood pressure (BP) and target organ damage, vascular risk and long-term patient prognosis is greater for measurements derived from around-the-clock ambulatory BP monitoring than in-clinic daytime ones. Numerous studies consistently substantiate the asleep BP mean is both an independent and a much better predictor of cardiovascular disease (CVD) risk than either the awake or 24 h means. Sleep-time hypertension is much more prevalent than suspected, not only in patients with sleep disorders, but also among those who are elderly or have type 2 diabetes, chronic kidney disease or resistant hypertension. Hence, cost-effective adequate control of sleep-time BP is of marked clinical relevance. Ingestion time, according to circadian rhythms, of hypertension medications of six different classes and their combinations significantly affects BP control, particularly sleep-time BP, and adverse effects. For example, because the high-amplitude circadian rhythm of the renin-angiotensin-aldosterone system activates during nighttime sleep, bedtime vs. morning ingestion of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers better reduces the asleep BP mean, with additional benefit, independent of medication terminal half-life, of converting the 24 h BP profile into more normal dipper patterning. The MAPEC (Monitorización Ambulatoria para Predicción de Eventos Cardiovasculares) study, first prospective randomized treatment-time investigation designed to test the worthiness of bedtime chronotherapy with ⩾1 conventional hypertension medications so as to specifically target attenuation of asleep BP, demonstrated, relative to conventional morning therapy, 61% reduction of total CVD events and 67% decrease of major CVD events, that is, CVD death, myocardial infarction, and ischemic and hemorrhagic stroke. The MAPEC study, along with other earlier conducted less refined trials, documents the asleep BP mean is the most significant prognostic marker of CVD morbidity and mortality; moreover, it substantiates attenuation of the asleep BP mean by a bedtime hypertension treatment strategy entailing the entire daily dose of ⩾1 hypertension medications significantly reduces CVD risk in both general and more vulnerable hypertensive patients, that is, those diagnosed with chronic kidney disease, diabetes and resistant hypertension.

Chronotherapy in practice: the perspective of the community pharmacist

BACKGROUND

Optimising the time of drug administration in alignment with circadian rhythms to enhance the clinical effect or minimise/avoid adverse effects is referred to as chronotherapy. Pharmacists have a key role in providing medicine related information, including counselling about the optimal time for medication administration. Where applicable, the principles of chronotherapy should underlie this aspect of medication counselling. Despite significant developments in the science of chronotherapy for specific pharmacological treatments, the perspective of pharmacists about their understanding and application of these principles in practice has not been explored.

OBJECTIVE

To explore community pharmacist's viewpoints about and experience with the application of chronotherapy principles in practice.

SETTING

Community pharmacies within metropolitan Sydney in New South Wales, Australia.

METHODS

Semi-structured, face to face interviews with a convenience sample of community pharmacists were conducted. All interviews were audio-recorded, transcribed verbatim and thematically analyzed using a 'grounded theory' approach, given the novelty of this area. Main outcome measure Community pharmacists' awareness, current practice and future practice support requirements about the principles of chronotherapy.

RESULTS

Twenty-five semi-structured interviews were conducted. Most participants reported encountering cases where clinical decision making about suggesting appropriate times of drug administration to patients was needed. Their approach was mainly pragmatic rather than based on theoretical principles of circadian variation in drug disposition or on current or emerging evidence; thus there was an evidence practice chasm in some cases. However, most participants believed they have an important role to play in counselling patients about optimal administration times and were willing to enact such roles or acquire skills/competence in this area.

CONCLUSION

Community pharmacists contribute to the safe and effective use of medications in providing the patients with information on optimal timing of drug administration during counselling. Further education, practical training and access to information may help pharmacists in translating principles of chronotherapy into the practice.

Ambulatory Blood Pressure Monitoring (ABPM) as the reference standard for diagnosis of hypertension and assessment of vascular risk in adults

New information has become available since the ISC, AAMCC, and SECAC released their first extensive guidedelines to improve the diagnosis and treatment of adult arterial hypertension. A critical assessment of evidence and a comparison of what international guidelines now propose are the basis for the following statements, which update the recommendations first issued in 2013. Office blood pressure (BP) measurements should no longer be considered to be the "gold standard" for the diagnosis of hypertension and assessment of cardiovascular risk. Relying on office BP, even when supplemented with at-home wake-time self-measurements, to identify high-risk individuals, disregarding circadian BP patterning and asleep BP level, leads to potential misclassification of 50% of all evaluated persons. Accordingly, ambulatory BP monitoring is the recommended reference standard for the diagnosis of true hypertension and accurate assessment of cardiovascular risk in all adults ≥18 yrs of age, regardless of whether office BP is normal or elevated. Asleep systolic BP mean is the most significant independent predictor of cardiovascular events. The sleep-time relative SBP decline adds prognostic value to the statistical model that already includes the asleep systolic BP mean and corrected for relevant confounding variables. Accordingly, the asleep systolic BP mean is the recommended protocol to diagnose hypertension, assess cardiovascular risk, and predict cardiovascular event-free interval. In men, and in the absence of compelling clinical conditions, reference thresholds for diagnosing hypertension are 120/70 mmHg for the asleep systolic/diastolic BP means derived from ambulatory BP monitoring. However, in women, in the absence of complicating co-morbidities, the same thresholds are lower by 10/5 mmHg, i.e., 110/65 mmHg for the asleep means. In high-risk patients, including those diagnosed with diabetes or chronic kidney disease, and/or those having experienced past cardiovascular events, the thresholds are even lower by 15/10 mmHg, i.e., 105/60 mmHg. Bedtime treatment with the full daily dose of ≥1 hypertension medications is recommended as a cost-effective means to improve the management of hypertension and reduce hypertension-associated risk. Bedtime treatment entailing the full daily dose of ≥1 conventional hypertension medications must be the therapeutic regimen of choice for the elderly and those with diabetes, resistant and secondary hypertension, chronic kidney disease, obstructive sleep apnea, and medical history of past cardiovascular events, among others, given their documented high prevalence of sleep-time hypertension.

Managing hypertension with ambulatory blood pressure monitoring

There has been a dramatic shift in the manner in which blood pressure (BP) is measured to provide far more comprehensive clinical information than that provided by a single set of office BP readings. Extensive clinical and epidemiological research shows an important role of ambulatory BP monitoring (ABPM) in the management of hypertensive patients. A 24-h BP profile helps to determine the absence of nocturnal dipping status and evaluate BP control in patients on antihypertensive therapy. The ability to detect white-coat or masked hypertension is enhanced by ambulatory BP monitoring. In 2001, the Center for Medicare and Medicaid Services approved ABPM for reimbursement for the identification of patients with white-coat hypertension. In 2011, the National Institute for Health and Clinical Excellence (NICE) in the UK published guidelines that recommended the routine use of ABPM in all patients suspected of having hypertension. The European Society of Hypertension (ESH) 2013 guidelines also support greater use of ABPM in clinical practice. While the advantages of ABPM are apparent from a clinical perspective, its use should be considered in relation to its cost, the complexity of data evaluation, as well as patient inconvenience. In this review, we evaluate the clinical importance of ABPM, highlighting its role in the current management of hypertension.

Ambulatory blood pressure monitoring in diabetes for the assessment and control of vascular risk

The diagnosis of hypertension and the clinical decisions regarding its treatment are usually based on daytime clinic blood pressure (BP) measurements. However, the correlation between BP levels and target organ damage, cardiovascular (CV) risk, and long-term prognosis, is higher for ambulatory (ABPM) than clinic measurements, both in the general population as well as in patients with diabetes. Moreover, there is consistent evidence in numerous studies that the asleep BP better predicts CV events than either the awake or 24h means. The prevalence of abnormal BP pattern and sleep-time hypertension is extensive in diabetes, often leading to inaccurate diagnoses of hypertension and its therapeutic control in the absence of complete and careful assessment of the entire 24h, i.e., daytime and night-time, BP pattern. Accordingly, ABPM should be the preferred method to comprehensively assess and decide the optimal clinical management of patients with diabetes directed to properly reduce elevated sleep-time BP, which might also lead to a significant reduction of CV events.

The 2015 Canadian Hypertension Education Program recommendations for blood pressure measurement, diagnosis, assessment of risk, prevention, and treatment of hypertension

The Canadian Hypertension Education Program reviews the hypertension literature annually and provides detailed recommendations regarding hypertension diagnosis, assessment, prevention, and treatment. This report provides the updated evidence-based recommendations for 2015. This year, 4 new recommendations were added and 2 existing recommendations were modified. A revised algorithm for the diagnosis of hypertension is presented. Two major changes are proposed: (1) measurement using validated electronic (oscillometric) upper arm devices is preferred over auscultation for accurate office blood pressure measurement; (2) if the visit 1 mean blood pressure is increased but < 180/110 mm Hg, out-of-office blood pressure measurements using ambulatory blood pressure monitoring (preferably) or home blood pressure monitoring should be performed before visit 2 to rule out white coat hypertension, for which pharmacologic treatment is not recommended. A standardized ambulatory blood pressure monitoring protocol and an update on automated office blood pressure are also presented. Several other recommendations on accurate measurement of blood pressure and criteria for diagnosis of hypertension have been reorganized. Two other new recommendations refer to smoking cessation: (1) tobacco use status should be updated regularly and advice to quit smoking should be provided; and (2) advice in combination with pharmacotherapy for smoking cessation should be offered to all smokers. The following recommendations were modified: (1) renal artery stenosis should be primarily managed medically; and (2) renal artery angioplasty and stenting could be considered for patients with renal artery stenosis and complicated, uncontrolled hypertension. The rationale for these recommendation changes is discussed.

Diagnosing and treating neurogenic orthostatic hypotension in primary care

In response to a change in posture from supine or sitting to standing, autonomic reflexes normally maintain blood pressure (BP) by selective increases in arteriovenous resistance and by increased cardiac output, ensuring continued perfusion of the central nervous system. In neurogenic orthostatic hypotension (NOH), inadequate vasoconstriction and cardiac output cause BP to drop excessively, resulting in inadequate perfusion, with predictable symptoms such as dizziness, lightheadedness and falls. The condition may represent a central failure of baroreceptor signals to modulate cardiovascular function, a peripheral failure of norepinephrine release from cardiovascular sympathetic nerve endings, or both. Symptomatic patients may benefit from both non-pharmacologic and pharmacologic interventions. Among the latter, two pressor agents have been approved by the US Food and Drug Administration: the sympathomimetic prodrug midodrine, approved in 1996 for symptomatic orthostatic hypotension, and the norepinephrine prodrug droxidopa, approved in 2014, which is indicated for the treatment of symptomatic neurogenic orthostatic hypotension caused by primary autonomic failure (Parkinson's disease, multiple system atrophy and pure autonomic failure). A wide variety of off-label options also have been described (e.g. the synthetic mineralocorticoid fludrocortisone). Because pressor agents may promote supine hypertension, NOH management requires monitoring of supine BP and also lifestyle measures to minimize supine BP increases (e.g. head-of-bed elevation). However, NOH has been associated with cognitive impairment and increases a patient's risk of syncope and falls, with the potential for serious consequences. Hence, concerns about supine hypertension - for which the long-term prognosis in patients with NOH is yet to be established - must sometimes be balanced by the need to address a patient's immediate risks.

Treatment of hypertension with chronotherapy: is it time of drug administration?

OBJECTIVE

To review evidence for dosing antihypertensives at bedtime and possible cardiovascular risk reduction.

DATA SOURCES

A PubMed, EMBASE, and Cochrane Controlled Trials database literature search (1990-September 2014) limited to human subjects was performed using the search terms hypertension, chronotherapy, ambulatory blood pressure, morning administration, evening administration, and antihypertensives. Additional references were identified from literature citations.

STUDY SELECTION

All prospective studies assessing cardiovascular outcomes or comparing morning to evening administration of antihypertensives were selected.

DATA SYNTHESIS

Compared with morning administration, dosing one or more antihypertensive medications at bedtime helps induce a normal circadian blood pressure pattern and reduces the risk of cardiovascular disease morbidity and mortality in individuals with hypertension. Similar results have been reported in high-risk individuals with diabetes, chronic kidney disease, and resistant hypertension. A lack of diversity among studied populations and reliance on subgroup analyses are among the limitations of these data. All antihypertensive medications have not been studied in chronotherapy and do not uniformly achieve desired results. The most substantial evidence exists for medications affecting the renin-angiotensin-aldosterone system.

CONCLUSIONS

Despite growing evidence and promise as a cost-effective strategy for reducing cardiovascular risk, chronotherapy is not uniformly recommended in the treatment of hypertension. Careful selection of patients and antihypertensives for chronotherapy is required. Further investigation is needed to evaluate the definitive impact of chronotherapy on cardiovascular outcomes.

Evening -versus morning- dosing drug therapy for chronic kidney disease patients with hypertension: a systematic review

BACKGROUND/AIMS

There is a strong correlation between non-dipping status and cardiovascular events in chronic kidney disease (CKD) patients. Our study is designed to identify the effect of evening administration of antihypertensive drugs to hypertensive CKD patients.

METHODS

A comprehensive search of Medline, Embase, the Chinese Biomedical Literature Database, Wanfang Data, Chinese National Knowledge Infrastructure, and the Cochrane Central Register of Controlled Trials was performed in July 2014. Concurrent controlled or crossover trials (including randomized and non-randomized experimental trials) designed to evaluate the effects of evening- versus morning-dosing hypertensive drug regimens on clinical outcomes in CKD patients with hypertension were included. All statistical analyses were performed using the RevMan software, which is available free from the Cochrane Collaboration.

RESULTS

Seven trials involving 1277 patients were identified, and the randomized controlled trials (RCTs) and non-randomized controlled trials (non-RCTs) were classified into two groups. Taking at least one blood pressure-lowering medication at bedtime was not shown to reduce total death (P=0.056) or cardiovascular death (P=0.059) but was shown to reduce total events (P<0.001) and major cardiovascular events (P<0.001) in both RCTs and non-RCTs. Compared with a morning dosing regimen, taking antihypertensive drug in the evening significantly lowered nighttime systolic blood pressure (SBP) (P<0.0001) and diastolic blood pressure (P<0.05) in patients in the RCTs but did not affect blood pressure in patients in the non-RCTs (P<0.05). There is limited evidence from one non-RCT that taking an antihypertensive drug (benazepril 10 mg) in the evening did not increase adverse events (P=0.72) or withdrawals due to adverse events (P=0.64).

CONCLUSIONS

A regimen of antihypertensive drugs in the evening should be considered for CKD patients with hypertension to lower nighttime blood pressure and help prevent total events and cardiovascular mortality. More studies are needed to verify the results of this study.

Diurnal and twenty-four hour patterning of human diseases: cardiac, vascular, and respiratory diseases, conditions, and syndromes

Various medical conditions, disorders, and syndromes exhibit predictable-in-time diurnal and 24 h patterning in the signs, symptoms, and grave nonfatal and fatal events, e.g., respiratory ones of viral and allergic rhinorrhea, reversible (asthma) and non-reversible (bronchitis and emphysema) chronic obstructive pulmonary disease, cystic fibrosis, high altitude pulmonary edema, and decompression sickness; cardiac ones of atrial premature beats and tachycardia, paroxysmal atrial fibrillation, 3rd degree atrial-ventricular block, paroxysmal supraventricular tachycardia, ventricular premature beats, ventricular tachyarrhythmia, symptomatic and non-symptomatic angina pectoris, Prinzmetal vasospastic variant angina, acute (non-fatal and fatal) incidents of myocardial infarction, sudden cardiac arrest, in-bed sudden death syndrome of type-1 diabetes, acute cardiogenic pulmonary edema, and heart failure; vascular and circulatory system ones of hypertension, acute orthostatic postprandial, micturition, and defecation hypotension/syncope, intermittent claudication, venous insufficiency, standing occupation leg edema, arterial and venous branch occlusion of the eye, menopausal hot flash, sickle cell syndrome, abdominal, aortic, and thoracic dissections, pulmonary thromboembolism, and deep venous thrombosis, and cerebrovascular transient ischemic attack and hemorrhagic and ischemic stroke. Knowledge of these temporal patterns not only helps guide patient care but research of their underlying endogenous mechanisms, i.e., circadian and others, and external triggers plus informs the development and application of effective chronopreventive and chronotherapeutic strategies.

Night blood pressure responses to atenolol and hydrochlorothiazide in black and white patients with essential hypertension

BACKGROUND

Night blood pressure (BP) predicts patient outcomes. Variables associated with night BP response to antihypertensive agents have not been fully evaluated in essential hypertension.

METHODS

We sought to measure night BP responses to hydrochlorothiazide (HCTZ), atenolol (ATEN), and combined therapy using ambulatory blood pressure (ABP) monitoring in 204 black and 281 white essential hypertensive patients. Initial therapy was randomized; HCTZ and ATEN once daily doses were doubled after 3 weeks and continued for 6 more weeks with the alternate medication added for combined therapy arms. ABP was measured at baseline and after completion of each drug. Night, day, and night/day BP ratio responses (treatment - baseline) were compared in race/sex subgroups.

RESULTS

Baseline night systolic BP and diastolic BP, and night/day ratios were greater in blacks than whites (P < 0.01, all comparisons). Night BP responses to ATEN were absent and night/day ratios increased significantly in blacks (P < 0.05). At the end of combined therapy, women, blacks, and those starting with HCTZ as opposed to ATEN had significantly greater night BP responses (P < 0.01). Variables that significantly associated with ATEN response differed from those that associated with HCTZ response and those that associated with night BP response differed from those that associated with day BP response.

CONCLUSIONS

In summary, after completion of HCTZ and ATEN therapy, women, blacks, and those who started with HCTZ had greater night BP responses. Reduced night BP response and increased night/day BP ratios occured with ATEN in blacks. Given the prognostic significance of night BP, strategies for optimizing night BP antihypertensive therapy should be considered.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov identifier NCT00246519.