Morning blood pressure surge, morning platelet aggregation, and silent cerebral infarction in older Japanese hypertensive patients

Controversies in hypertension therapy: bedtime dosing or daytime dosing?

Hypertension management strategies have evolved from solely controlling office blood pressure (BP) to comprehensive 24-h BP regulation. This review synthesizes current evidence on the timing of antihypertensive medication, with a focus on circadian BP rhythms and patients with specific BP patterns or comorbidities. Bedtime dosing may benefit individuals with nocturnal hypertension and nondipper BP patterns, but large trials, such as the TIME study, have shown no significant cardiovascular outcome differences between morning and bedtime dosing. However, the optimal timing of antihypertensive medication for patients with distinct BP rhythms or comorbidities remains uncertain. Future research should investigate the potential benefits of personalized medication timing tailored to BP patterns and clinical conditions. Additionally, treatment strategies should consider BP rhythms, comorbidities, and adherence to optimize outcomes, paving the way for more effective management of hypertensive patients with complex clinical profiles.

Correlation of blood pressure levels at different time periods throughout the day with total CSVD burden and MRI imaging markers

Purpose

Hypertension is an important risk factor for atherosclerotic cerebral small vessel disease (CSVD). Higher blood pressure is associated with a higher CSVD burden and the presence of relevant magnetic resonance imaging (MRI) markers. However, the effect of blood pressure level on CSVD burden and imaging markers including white matter hyperintensity (WHM), lacune, enlarged perivascular spaces (EPVS), and cerebral microbleed (CMB) remains unknown. The purpose of this study was to investigate the correlation between blood pressure level and CSVD burden at different time periods throughout the day.

Methods

In total, 144 in-patients with CSVD (66.4 ± 9.8 years, 50% male) were enrolled and underwent brain MRI, and 24-h ambulatory blood pressure was assessed. Patients were categorized into five groups according to their MRI-evaluated total CSVD burden scores (0-4). Spearman's correlation analysis was performed to examine the correlation between blood pressure levels at different time periods and the total CSVD score or the markers of periventricular WMH, deep WMH, lacune, EPVS, and CMB.

Results

Of the 144 patients, 83.3% (120/144) harbored one or more CSVD markers of interest. The systolic blood pressure (SBP) of 24-h, daytime, nighttime, and morning differed significantly among the five groups. The SBP levels increased significantly with the total CSVD scores during 24 h (P = 0.018), daytime (P = 0.018), and nighttime (P = 0.035). Spearman's correlation analysis demonstrated that the SBP of 24 h, daytime, nighttime, and morning and the diastolic blood pressure (DBP) of 24 h and morning positively and significantly correlated with the total CSVD score (P < 0.05). A logistic regression analysis indicated that both morning SBP and DBP were independent risk factors for total CSVD burden (OR = 1.13, 95% CI: 1.02-1.23, P = 0.015; OR = 1.19, 95% CI: 1.06-1.33, P = 0.005). Spearman's correlation analysis indicated a significant positive correlation between morning SBP and higher deep WMH Fazekas score (r = 0.296, P < 0.001), EPVS grade in the basal ganglia (r = 0.247, P = 0.003), and the presence of lacune (r = 0.173, P = 0.038) and CMB (r = 0.326, P < 0.001). Morning DBP only correlated positively with the presence of CMB (r = 0.292, P < 0.001).

Conclusion

Higher SBP signficantly correlated with total CSVD burden in patients with atherosclerotic CSVD. Early morning blood pressure level is an important indicator to reflect the severity of CSVD patients.

The Association between Diverticular Rebleeding and Early-Morning Blood Pressure and Surge: A Prospective Observational Trial

INTRODUCTION

Colonic diverticular bleeding is the major cause of lower gastrointestinal bleeding. Hypertension is a major risk factor for diverticular rebleeding. Direct evidence of an association between actual 24-h blood pressure (BP) and rebleeding is lacking. Therefore, we analyzed the association between 24-h BP and diverticular rebleeding.

METHODS

We performed a prospective observational cohort trial involving hospitalized patients with colonic diverticular bleeding. We performed 24-h BP measurements (ambulatory BP monitoring [ABPM]) in the patients. The primary outcome was diverticular rebleeding. We evaluated the 24-h BP difference and the morning and pre-awaking BP surge between rebleeding and non-rebleeding patients. Morning BP surge was defined as early-morning systolic BP minus the lowest night systolic BP >45 mm Hg (highest quartile of morning BP surge). The pre-awaking BP surge was defined as the difference between morning BP and pre-awaking BP.

RESULTS

Of 47 patients, 17 were excluded, leaving 30 who underwent ABPM. Of the 30 patients, 4 (13.33%) had rebleeding. The mean 24-h systolic and diastolic BP were 125.05 and 76.19 mm Hg in rebleeding patients and 129.98 and 81.77 mm Hg in non-rebleeding patients, respectively. Systolic BP at 5:00 (difference -23.53 mm Hg, p = 0.031) and 11:30 (difference -31.48 mm Hg, p = 0.006) was significantly lower in rebleeding patients than in non-rebleeding patients. Diastolic BP at 2:30 (difference -17.75 mm Hg, p = 0.023) and 5:00 (difference -16.12 mm Hg, p = 0.043) was significantly lower in rebleeding patients than in non-rebleeding patients. A morning surge was observed in one rebleeding patient and no non-rebleeding patients. The pre-awaking surge was significantly higher in rebleeding patients (28.44 mm Hg) than in non-rebleeding patients (9.30 mm Hg) (p = 0.015).

CONCLUSION

Lower BP in the early-morning and a higher pre-awaking surge were risk factors for diverticular rebleeding. A 24-h ABPM can identify these BP findings and reduce the risk of rebleeding by enabling interventions in patients with diverticular bleeding.

Insight on Cardiac Chronobiology and Latest Developments of Chronotherapeutic Antihypertensive Interventions for Better Clinical Outcomes

Cardiac circadian rhythms are an important regulator of body functions, including cardiac activities and blood pressure. Disturbance of circadian rhythm is known to trigger and aggravate various cardiovascular diseases. Thus, modulating the circadian rhythm can be used as a therapeutic approach to cardiovascular diseases. Through this work, we intend to discuss the current understanding of cardiac circadian rhythms, in terms of quantifiable parameters like BP and HR. We also elaborate on the molecular regulators and the molecular cascades along with their specific genetic aspects involved in modulating circadian rhythms, with specific reference to cardiovascular health and cardiovascular diseases. Along with this, we also presented the latest pharmacogenomic and metabolomics markers involved in chronobiological control of the cardiovascular system along with their possible utility in cardiovascular disease diagnosis and therapeutics. Finally, we reviewed the current expert opinions on chronotherapeutic approaches for utilizing the conventional as well as the new pharmacological molecules for antihypertensive chronotherapy.

Ambient fine particulate pollution hysteresis triggers wake-up stroke and rapidly triggers non-wake-up stroke: a case-crossover study

Atmospheric pollutants increase the risk of acute ischemic stroke (AIS) which has been widely reported. However, little is known about the relationships between air pollution and specific subsets of AIS, such as wake-up stroke (WUS) and non-wake-up stroke (non-WUS). This study aimed to explore the relationship between WUS and non-WUS and atmospheric pollutants. A total of 1432 patients (331 WUS patients and 1101 non-WUS patients) were admitted to a tertiary hospital from 2016 to 2019. A time-stratified case-crossover design and a conditional logistic regression model to study the associations of change in pollutant concentration with WUS and non-WUS events were constructed. Data analysis revealed that WUS-related risks increased 48 to 72 h after the increase in the PM_2.5 concentration (each 10 μg/m³ increase, lag 0-72 h) [threshold OR (95% CI):18 μg/m³ 1.03 (0.94-1.11), 35 μg/m³ 1.01 (0.92-1.12), 50 μg/m³ 1.04 (0.91-1.19)]; the non-WUS-related risk increased 1 to 6 h after the increase in the PM_2.5 concentration (each 10 μg/m³ increase, lag 0-1 h) [threshold OR (95% CI):18 μg/m³ 1.01 (0.98-1.03), 35 μg/m³ 1.00 (0.97-1.04), 50 μg/m³ 1.01 (0.96-1.05)] (lag 0-6 h) [threshold OR (95% CI): 18 μg/m³ 1.00 (0.97-1.03), 35 μg/m³ 1.00 (0.97-1.04), 50 μg/m³ 1.01 (0.97-1.06)]; O₃ exposure was related to WUS events, and its impact on WUS events was stronger and longer-lasting (1-96 h) than its impact on non-WUS events (1-6 h). Greater than or equal to 65 years of age, overweight (BMI ≥ 25), and diabetes had a significantly greater risk of WUS associated with increased PM_2.5 concentration in the previous 12-96 h than patients without these conditions. Patients with hypertension and smoking had a significant risk of non-WUS associated with increased PM_2.5 concentration in the previous 1-6 h. The increase in PM_2.5 concentration in the cold season increased the risk of both WUS and non-WUS events. Ambient air pollution hysteresis triggers WUS and rapidly triggers non-WUS, even if the degree of pollutant is relatively low. Patients with elderly, overweight, and diabetes appeared particularly susceptible to WUS, and patients with hypertension and smoking history were susceptible to non-WUS. We need to expand the sample for further investigation into mechanisms by which environmental pollutants trigger WUS or non-WUS.

The Association of Dietary Vitamin Intake Time Across a Day With Cardiovascular Disease and All-Cause Mortality

Background

Chrono-nutrition emphasized the importance of the intake time; however, less is known about the impact of dietary vitamin intake time on health. This study aimed to examine our hypothesis about which vitamin intake time could influence the natural course of cardiovascular disease (CVD).

Methods

A total of 27,455 adults enrolled in the National Health and Nutrition Examination Survey (NHANES) during 2003–2014 were recruited. The 12 dietary vitamin intakes in the morning, afternoon, and evening were categorized into tertiles or quartiles. Cox-proportional hazard regression models were developed to evaluate the association of vitamin intake time with CVD and all-cause mortalities.

Results

Compared with participants in the lowest quartile, participants in the highest quartile of dietary VB2 intake in the morning had significantly lowest mortality risk of CVD [hazard ratio (HR)_VB2 = 0.75, 95% CI: 0.60–0.94, p = 0.017]; whereas, participants in the highest quartile of dietary-vitamin B6 (VB6), vitamin C (VC), vitamin E (VE), and folate-equivalent consumed in the evening showed the lowest risks of CVD (HR_VB6 = 0.77, 95% CI: 0.60–0.99, p = 0.103; HR_VC = 0.80, 95% CI: 0.65–0.98, p = 0.050; HR_VE = 0.75, 95% CI: 0.56–0.99, p = 0.032; HR_{folate–equivalent} = 0.78, 95% CI: 0.63–0.97, p = 0.116) and all-cause mortalities (HR_VB6 = 0.81, 95% CI: 0.71–0.93, p = 0.006; HR_VC = 0.85, 95% CI: 0.76–0.95, p = 0.004; HR_VE = 0.84, 95% CI: 0.72–0.97, p = 0.011; HR_{folate–equivalent} = 0.80, 95% CI: 0.71–0.90, p = 0.001). Moreover, equivalently replacing 10% intake of dietary VB6, VC, VE, and folate-equivalent in the morning with evening were associated with 4% (HR_VB6 = 0.96, 95% CI: 0.92–0.99), 5% (HR_VC = 0.95, 95% CI: 0.92–0.99), 4% (HR_VE = 0.96, 95% CI: 0.91–0.99), and 5% (HR_{folate–equivalent} = 0.95, 95% CI: 0.92–0.99) lower risk of CVD mortality.

Conclusion

This study found that the optimal intake time of dietary VB2 was in the morning, and the optimal intake times of dietary VB6, VC, VE, and folate-equivalent were in the evening.

Pathophysiologic mechanisms, neuroimaging and treatment in wake-up stroke

Wake-up stroke (WUS) or ischemic stroke occurring during sleep accounts for 14%-29.6% of all ischemic strokes. Management of WUS is complicated by its narrow therapeutic time window and attributable risk factors, which can affect the safety and efficacy of administering intravenous (IV) tissue plasminogen activator (t-PA). This manuscript will review risk factors of WUS, with a focus on obstructive sleep apnea, potential mechanisms of WUS, and evaluate studies assessing safety and efficacy of IV t-PA treatment in WUS patients guided by neuroimaging to estimate time of symptom onset. The authors used PubMed (1966 to March 2018) to search for the term "Wake-Up Stroke" cross-referenced with "pathophysiology," ''pathogenesis," "pathology," "magnetic resonance imaging," "obstructive sleep apnea," or "treatment." English language Papers were reviewed. Also reviewed were pertinent papers from the reference list of the above-matched manuscripts. Studies that focused only on acute Strokes with known-onset of symptoms were not reviewed. Literature showed several potential risk factors associated with increased risk of WUS. Although the onset of WUS is unknown, a few studies investigated the potential benefit of magnetic resonance imaging (MRI) in estimating the age of onset which encouraged conducting clinical trials assessing the efficacy of MRI-guided thrombolytic therapy in WUS.

Association of Circadian Rhythm of Blood Pressure and Cerebral Small Vessel Disease in Community-Based Elderly Population

BACKGROUND

Although it is accepted that the etiology of cerebral small vessel disease (CSVD) is associated with cardiovascular risk factors, the association between CSVD and the circadian rhythm of blood pressure (BP) is unclear. We aimed to determine if such an association existed in the elderly population.

METHOD

White matter hyperintensities (WMHs), lacunes, microbleeds, nocturnal dipping pattern (NDP), and morning surge in systolic blood pressure (SBP) were assessed in 2,091 participants ≥60 years of age.

RESULTS

During an average of 63 months of follow-up, WMH and the WMH-to-intracranial volume ratio were significantly increased in extreme dippers, nondippers, and reverse dippers than those in dippers (p < .001). For new-incident Fazekas scale ≥2, the hazard ratios were 1.77 (95% confidence interval [CI], 1.09-2.86) for extreme dippers, 2.20 (95% CI, 1.48-3.28) for nondippers, and 2.43 (95% CI, 1.59-3.70) for reverse dippers compared with dippers, and 1.04 (95% CI, 0.81-1.35) for higher morning surge compared with lower morning surge. Nondippers and reverse dippers were associated with higher risks of new-incident lacunes and microbleeds than dippers (p < .05). Higher morning surge was associated with a higher risk of new-incident microbleeds than lower morning surge (p < .05).

CONCLUSION

NDPs in SBP played an important role in CSVD, and the morning surge in SBP was associated with cerebral microbleeds in community-based elderly population beyond the average SBP level.

Moderate morning rise in blood pressure has lowest risk of stroke but only in women

BACKGROUND

The morning period which is recognized as the highest risk for cardiovascular events is associated with a surge in blood pressure (BP). However, it is unclear what aspect of this rise is important.

AIM

To determine whether the rate of rise (RoR), the magnitude (day night difference) or the product [BP power (BPPower)] is associated with increased cardiovascular risk.

METHODS

We developed a logistic equation method to fit individual 24-h patterns of BP to determine RoR, amplitude and BPPower using the ambulatory recordings from the Ohasama study including 564 men and 971 women (16.6 years follow-up).

RESULTS

Men had a higher risk of cardiovascular events than women (24, 16%, P < 0.001). Age and night BP were strong linear risk predictors. In men sorting risk by quintiles of BPPower (adjusted for age, night BP, smoking status) revealed no clear linear or nonlinear pattern. However, in women BPPower had a U-shaped relationship with the lowest risk being the 2-3rd quintile for all cardiovascular events (Pquadratic = 0.01) including cardiovascular death (Pquadratic = 0.03) and nonfatal stroke (Pquadratic = 0.02). A similar but less clear trend was observed with the RoR but only stroke (infarct) reached significance (Pquadratic = 0.03) while sorting by range showed a U shaped pattern for combined cardiovascular events (Pquadratic = 0.04).

CONCLUSION

These findings suggest that the morning BPPower is an important independent risk factor for predicting cardiovascular events and stroke but only in women with median levels having the lowest risk.

Nighttime administration of high-dose, sustained-release melatonin does not decrease nocturnal blood pressure in African-American patients: Results from a preliminary randomized, crossover trial

OBJECTIVES

This preliminary study tested whether a high-dose, sustained-release form of melatonin reduced 24-hour blood pressure in African-Americans.

DESIGN

Randomized, placebo-controlled, crossover pilot study of 40 self-defined African-American patients with essential hypertension.

SETTINGS/LOCATION

Urban, academic medical center and associated outpatient clinics.

INTERVENTIONS

Patients ingested either melatonin (high dose [24 mg], sustained-release formulation] or placebo in randomized order over a 4-week period.

OUTCOME MEASURES

Mean nighttime and daytime systolic and diastolic blood pressures, as measured with 24-hour ambulatory blood pressure monitors. The primary outcome was mean nighttime systolic blood pressure.

RESULTS

There were no statistically differences between melatonin and placebo conditions in mean nighttime or daytime systolic or diastolic blood pressures.

CONCLUSIONS

In contrast with studies in other populations, this preliminary study showed that nighttime dosing of continuous-release melatonin had no significant effect on nocturnal blood pressure in African Americans with essential hypertension when compared to placebo.

Regulation of Cerebral Blood Flow: Response to Cytochrome P450 Lipid Metabolites

There have been numerous reviews related to the cerebral circulation. Most of these reviews are similar in many ways. In the present review, we thought it important to provide an overview of function with specific attention to details of cerebral arterial control related to brain homeostasis, maintenance of neuronal energy demands, and a unique perspective related to the role of astrocytes. A coming review in this series will discuss cerebral vascular development and unique properties of the neonatal circulation and developing brain, thus, many aspects of development are missing here. Similarly, a review of the response of the brain and cerebral circulation to heat stress has recently appeared in this series (8). By trying to make this review unique, some obvious topics were not discussed in lieu of others, which are from recent and provocative research such as endothelium-derived hyperpolarizing factor, circadian regulation of proteins effecting cerebral blood flow, and unique properties of the neurovascular unit. © 2018 American Physiological Society. Compr Physiol 8:801-821, 2018.

Endovascular Thrombectomy in Wake-Up Stroke and Stroke with Unknown Symptom Onset

BACKGROUND AND PURPOSE

Mechanical thrombectomy in acute ischemic stroke within 6 hours of symptom onset is effective and safe. However, in many patients, information on the beginning of symptoms is not available. Patients can be divided into those with wake-up stroke and daytime-unwitnessed stroke. Evidence on outcome and complications after mechanical thrombectomy in wake-up stroke and daytime-unwitnessed stroke is rare. A potential beneficial effect of mechanical thrombectomy in selected patients with wake-up stroke or daytime-unwitnessed stroke is suspected.

MATERIALS AND METHODS

We analyzed 1073 patients with anterior circulation stroke undergoing mechanical thrombectomy between 2010 and 2016. Patients with wake-up stroke and daytime-unwitnessed stroke were compared with controls receiving mechanical thrombectomy as the standard of care. We assessed good functional outcome (mRS ≤ 2 at 3 months), mortality rates, and frequencies of symptomatic intracranial hemorrhage. Subgroup analyses tried to detect influences of patient selection via further imaging modalities (MR imaging, CTP; wake-up stroke [advanced], daytime-unwitnessed stroke [advanced]) on outcome and safety.

RESULTS

There was no significant difference in good functional outcome between patients with wake-up stroke and controls (35.9% versus 38.3%, P = .625). Outcome in patients with daytime-unwitnessed stroke was inferior compared with controls (27.3%, P = .007). Groups did not differ in all-cause mortality at day 90 (P = .224) and the rate of symptomatic intracranial hemorrhage (P = .292). Advanced imaging improved the frequency of good functional outcome (non-wake-up stroke [advanced] versus wake-up stroke [advanced]: OR, 2.92; 95% CI, 1.32-6.45; non-daytime-unwitnessed stroke [advanced] versus daytime-unwitnessed stroke [advanced]: OR, 2.09; 95% CI, 1.03-4.25) with an additional reduction in all-cause mortality (non-daytime-unwitnessed stroke [advanced] versus daytime-unwitnessed stroke [advanced]: OR, 0.42; 95% CI, 0.20-0.88).

CONCLUSIONS

Mechanical thrombectomy in selected patients with wake-up stroke allows a good functional outcome comparable with that of controls. Outcome after mechanical thrombectomy in daytime-unwitnessed stroke seems to be inferior compared with that in controls. Advanced imaging modalities may increase the frequency of good functional outcome in both patients with wake-up stroke and daytime-unwitnessed stroke.

Magnitude of Morning Surge in Blood Pressure Is Associated with Sympathetic but Not Cardiac Baroreflex Sensitivity

The ability of the arterial baroreflex to regulate blood pressure may influence the magnitude of the morning surge in blood pressure (MSBP). The aim was to investigate the relationships between sympathetic and cardiac baroreflex sensitivity (BRS) and the morning surge. Twenty-four hour ambulatory blood pressure was recorded in 14 young individuals. The morning surge was defined via the pre-awakening method, which is calculated as the difference between mean blood pressure values 2 h before and 2 h after rising from sleep. The mean systolic morning surge, diastolic morning surge, and morning surge in mean arterial pressures were 15 ± 2, 13 ± 1, and 11 ± 1 mmHg, respectively. During the laboratory protocol, continuous measurements of blood pressure, heart rate, and muscle sympathetic nerve activity (MSNA) were made over a 10-min period of rest. Sympathetic BRS was quantified by plotting MSNA burst incidence against diastolic pressure (sympathetic BRS_inc), and by plotting total MSNA against diastolic pressure (sympathetic BRS_total). Cardiac BRS was quantified using the sequence method. The mean values for sympathetic BRS_inc, sympathetic BRS_total and cardiac BRS were −1.26 ± 0.26 bursts/100 hb/mmHg, −1.60 ± 0.37 AU/beat/mmHg, and 13.1 ± 1.5 ms/mmHg respectively. Significant relationships were identified between sympathetic BRS_inc and the diastolic morning surge (r = 0.62, p = 0.02) and the morning surge in mean arterial pressure (r = 0.57, p = 0.03). Low sympathetic BRS was associated with a larger morning surge in mean arterial and diastolic blood pressure. Trends for relationships were identified between sympathetic BRS_total and the diastolic morning surge (r = 0.52, p = 0.066) and the morning surge in mean arterial pressure (r = 0.48, p = 0.095) but these did not reach significance. There were no significant relationships between cardiac BRS and the morning surge. These findings indicate that the ability of the baroreflex to buffer increases in blood pressure via reflexive changes in MSNA may play a role in determining the magnitude of the MSBP.

Morning Blood Pressure Surge, Dipping, and Risk of Coronary Events in Elderly Treated Hypertensive Patients

BACKGROUND

The independent prognostic significance of morning surge (MS) of blood pressure (BP) is not yet clear. We investigated the association between MS of systolic BP and risk of coronary events in elderly treated hypertensive patients.

METHODS

The occurrence of coronary events was evaluated in 1,191 elderly treated hypertensive patients (age range 60-90 years). Subjects were divided according to tertiles of MS of systolic BP of the population as a whole, by dipping status and by group-specific tertiles of MS of systolic BP in dippers and nondippers.

RESULTS

During the follow-up (9.1 ± 4.9 years, range 0.4-20 years), 120 coronary events occurred. In the population as a whole, coronary event risk was not significantly associated with tertiles of MS of systolic BP, whereas nondippers were at higher risk than dippers. When nondippers and dippers were analyzed separately, by group-specific tertiles of MS of systolic BP, coronary event risk was associated with MS of systolic BP in dippers but not in nondippers. After adjustment for various covariates, Cox regression analysis showed that dippers in the third tertile (>23 mm Hg) of MS of systolic BP (hazard ratio 1.912, 95% confidence interval 1.048-3.488, P = 0.03) and nondippers (hazard ratio 1.739, 95% confidence interval 1.074-2.815, P = 0.02) were at higher coronary event risk than dippers with MS of systolic BP <23 mm Hg .

CONCLUSIONS

In elderly treated hypertensive patients, high MS of systolic BP predicts coronary events in dippers but not in nondippers. Nondippers, however, show higher risk of coronary events independently of MS in systolic BP.

Relationship between mean platelet volume and morning blood pressure surge in newly diagnosed hypertensive patients

OBJECTIVE

Morning blood pressure surge (MBPS) is an independent predictor of atherothrombotic cardiovascular events in hypertensive patients. There is evidence from studies supporting the validity of mean platelet volume (MPV) as a marker of vascular risk and predictor of thrombotic complications. The aim of this study is to investigate the relationship between MPV and MBPS in hypertensive patients.

METHODS

Measurements were obtained from 298 patients with newly diagnosed essential hypertension (Mean age: 51.9 ± 11.7 years). The patients were divided into two groups (MPV(low) group; <10.8 fL, MPV(high) group; ≥ 10.8 fL). The MBPS was calculated as mean systolic BP during the 2 hours after awaking minus the mean systolic BP during the 1 hour that included the lowest sleep BP.

RESULTS

MPV was independently associated with MBPS (β=0.554, p<0.001) and hs-CRP level (β=0.286, p<0.001).

CONCLUSION

Finally, higher MPV values related to enhanced MBPS which are associated with atherothrombotic cardiovascular events.

Mean platelet volume in patients with obstructive sleep apnea and its relationship with simpler heart rate derivatives

Some studies show increased mean platelet volume (MPV) in obstructive sleep apnea (OSA). The aim of this study was to evaluate MPV in OSA patients without cardiovascular risk factors and the possible association of heart rate derivatives with MPV. A total of 82 patients (aged 30–70 years) were divided into 2 groups according to the presence of either OSA or non-OSA as the control group. The OSA group consisted of 52 patients and the control group consisted of 30 subjects. Neither group was significantly different in terms of MPV values as well as heart rate (HR) derivatives such as minimum HR, maximum HR, the difference between maximum HR and minimum HR, mean HR, and heart rate performance index (HRPI) [(HR max. − HR min.)/HR mean] (P > 0.05 for all variables). In multivariate analysis, platelet count and percentages of recording time spent at arterial oxygen saturation < 90% significant variables are associated with MPV (β ± SE: −0.004 ± 0.002, 95% CI, −0.008 to −0.001; P = 0.034) and (β ± SE: 2.93 ± 1.93, 95% CI, 0.167 to 5.69; P = 0.038). Consequently, our findings predominantly suggest that there is a casual and reciprocal interaction between MPV and autonomic activation.

Wake-up stroke and stroke of unknown onset: a critical review

Patients, who wake up with an ischemic stroke, account for a large number of the total stroke population, due to circadian morning predominance of stroke. Currently, this subset of patients is excluded from revascularization-therapy since no exact time of onset is known. A large group of these patients might be eligible for therapy. In this review, we assessed the current literature about the hypothesis that wake-up-strokes occur just prior on awakening and if this subgroup differs in characteristics compared to the overall stroke population. We looked at the safety and efficacy of thrombolysis and interventional techniques in the group of patients with unknown stroke-onset. We performed a meta-analysis of the diagnostic accuracy of the diffusion-FLAIR mismatch in identifying stroke within 3 and 4.5 h. The different imaging-selection criteria that can be used to treat these patients are discussed. Additional research on imaging findings associated with recent stroke and penumbral imaging will eventually lead to a shift from a rigid time-frame based therapy to a tissue-based individualized treatment approach.

Race, plasma renin activity, and morning blood pressure surge--results from the Dietary Approaches to Stop Hypertension trial

BACKGROUND

The association of preawake (difference between pre- and postwaking blood pressure (BP)) and sleep-through surge (difference between sleeping nadir and postwaking BP) with cardiovascular events is unclear. Examination of factors associated with surge may provide novel insights. We examined the association of race, which associates with nocturnal dipping, and plasma renin activity (PRA) with preawake and sleep-through surge among individuals on a controlled diet.

METHODS

We performed a post hoc analysis of 323 subjects from the Dietary Approaches to Stop Hypertension trial who had available 24-hour BP data and who ingested a control diet during a 3-week run-in period. Linear regression models were fit to estimate the association of race and PRA with preawake and sleep-through surge.

RESULTS

Of the 323 individuals, 55% were black, 53% were men, and the average age was 45 years. After controlling for other factors, black race was associated with a 3.2mm Hg lower preawake and a 3.7mm Hg lower sleep-through surge compared with nonblacks. In nonblacks, higher PRA was associated with greater preawake surge only. There was no association of PRA with either preawake or sleep-through surge in blacks. Additional adjustment for dipping status resulted in attenuation of the race-surge associations.

CONCLUSIONS

Black race is associated with lower preawake and sleep-through surge compared with nonblacks, but the effect is partially attenuated by dipping status. Higher PRA appears to be associated with a higher preawake surge in nonblacks only. Further research should address if morning surge is definitively associated with clinical outcomes in racial subgroups, independent of dipping.

Orthostatic hypertension-a new haemodynamic cardiovascular risk factor

Orthostatic hypertension-a condition characterized by a hyperactive pressor response to orthostatic stress-is an emerging risk factor for cardiovascular disease and is associated with hypertensive target-organ damage (resulting in silent cerebrovascular disease, left ventricular hypertrophy, carotid atherosclerosis and/or chronic kidney disease) and cardiovascular events (such as coronary artery disease and lacunar stroke). The condition is also considered to be a form of prehypertension as it precedes hypertension in young, normotensive adults. Orthostatic blood pressure changes can be assessed using orthostatic stress tests, including clinic active standing tests, home blood pressure monitoring and the head-up tilting test. Devices for home and for ambulatory blood pressure monitoring that are equipped with position sensors and do not induce a white-coat effect have increased the sensitivity and specificity of diagnosis of out-of-clinic orthostatic hypertension. Potential major mechanisms of orthostatic hypertension are sympathetic hyperactivity (as a result of hypersensitivity of the cardiopulmonary and arterial baroreceptor reflex) and α-adrenergic hyperactivation. Orthostatic hypertension is also associated with morning blood pressure surge and extreme nocturnal blood pressure dipping, both of which increase the pulsatile haemodynamic stress of central arterial pressure and blood flow in patients with systemic haemodynamic atherothrombotic syndrome.

A systematic comparison of the properties of clinically used angiotensin II type 1 receptor antagonists

Angiotensin II type 1 receptor antagonists (ARBs) have become an important drug class in the treatment of hypertension and heart failure and the protection from diabetic nephropathy. Eight ARBs are clinically available [azilsartan, candesartan, eprosartan, irbesartan, losartan, olmesartan, telmisartan, valsartan]. Azilsartan (in some countries), candesartan, and olmesartan are orally administered as prodrugs, whereas the blocking action of some is mediated through active metabolites. On the basis of their chemical structures, ARBs use different binding pockets in the receptor, which are associated with differences in dissociation times and, in most cases, apparently insurmountable antagonism. The physicochemical differences between ARBs also manifest in different tissue penetration, including passage through the blood-brain barrier. Differences in binding mode and tissue penetration are also associated with differences in pharmacokinetic profile, particularly duration of action. Although generally highly specific for angiotensin II type 1 receptors, some ARBs, particularly telmisartan, are partial agonists at peroxisome proliferator-activated receptor-γ. All of these properties are comprehensively reviewed in this article. Although there is general consensus that a continuous receptor blockade over a 24-hour period is desirable, the clinical relevance of other pharmacological differences between individual ARBs remains to be assessed.