Twenty-four hour systolic blood pressure predicts long-term mortality following acute stroke

John J, Van Iterson EH, Laffin LJ. Association of pulse pressure with death, myocardial infarction, and stroke among cardiovascular outcome trial participants

Background

Prior evidence demonstrates that pulse pressure (PP), a surrogate marker of arterial stiffness, is an independent risk factor for mortality and major adverse cardiovascular (CV) events.

Objectives

The study aimed to identify the association of PP with death, myocardial infarction, and stroke among participants enrolled in large CV outcome clinical trials and determine if this association was impacted by pre-existing CV disease, or specific CV risk factors.

Methods

A total of 65,382 individuals, ages 19 to 98 years, that were enrolled in one of five CV outcome trials were analyzed. Baseline demographics, history, blood pressures, and medications were collected. Univariate and multivariable analyses were conducted to explore temporal patterns, risks, and adjusted survival rates.

Results

Mean baseline PP was 52 ± 12 mmHg. For every 10 mmHg increase in PP, there was an increased risk of death, stroke, or myocardial infarction (hazard ratio (HR) 1.11, 95 % CI 1.08 to 1.14, p < 0.001). Similarly, a PP ≥ 60 mmHg demonstrated an HR of 1.27 (95 % CI 1.19 to 1.36, p < 0.001) compared with PP < 60 mmHg. A similar association existed for all subgroups analyzed except for participants with a history of stroke where increasing PP did not increase risk (HR 1.02, 95 % CI 0.95 to 1.10, p = 0.53). PP was a better predictor of adverse outcomes when compared to both systolic and diastolic blood pressures using the AIC and C-index.

Conclusions

Among participants enrolled in CV outcome trials, baseline PP is associated with increased risk of death, myocardial infarction, and stroke for those with pre-existing CV disease and risk factors with the exception of a prior history of stroke.

Functional recovery and blood pressure on acute post-stroke setting

Objectives

This study aims to evaluate the effects of blood pressure (BP) on functional recovery and length of stay (LOS) in post-stroke patients in an acute rehabilitation facility (ARF).

Patients and methods

A total of 116 ischemic stroke patients (60 males, 56 females; mean age 70.0±12.8 years; range, 37 to 93 years) who were admitted to the ARF between January 2012 and September 2012 were included. Daily BP measurements with mean systolic and diastolic BP values and Functional Independent Measure (FIM) scores at the time of admission and discharge were measured. The LOS and systolic and diastolic BP ranges were also recorded.

Results

There was no significant correlation between the BP and FIM scores. The mean diastolic BP was positively correlated with admission (rs=0.316, p=0.01) and discharge (rs=0.287, p=0.002), FIM scores, and FIM effectiveness (rs=0.185, p=0.047) and negatively correlated with age (r=-0.449, p<0.001) and LOS (rs=-0.189, p=0.042). The LOS in hospital was negatively correlated with FIM scores at admission (rs=-0.585, p<0.001) and discharge (rs=-0.352, p<0.001) and positively correlated with FIM score changes (rs=0.414, p<0.001).

Conclusion

Our study results show that diastolic BP in the subacute phase of stroke does not have a major impact on the functional recovery and LOS in post-stroke patients. However, there is a significant correlation between diastolic BP values and FIM efficiency.

The effects of diffusion and perfusion MRI mismatch on the admission blood glucose and blood pressure values measured in the first 12 hours of acute stroke

Patients with severe stroke and salvageable brain tissue at admission, who have higher glycaemic and blood pressure levels, may have a risk of iatrogenic hypoglycemia/iatrogenic hypotension. In this study, we examined the relationship between the presence of diffusion-weighted imaging (DWI)/perfusion-weighted imaging (PWI) mismatch, admission blood glucose level, and admission blood pressure level in patients who were admitted in the first 12 hours after onset. We studied 212 patients who were prospectively and consecutively registered to the stroke unit from 2006 to 2009. Correlations between mismatch and admission blood pressure level (ABPL) and admission blood glucose level (ABGL) were analyzed using multivariate logistic regression. Mismatch (P = .064, adjusted OR = 2.297, 95% CI, 0.953-5.536) was not associated with a high ABGL in the whole group. However, after excluding patients with diabetes mellitus (DM) (n = 67, 35%), mismatch (P = .033, adjusted OR = 3.801, 95% CI, 1.110-13.015), an impaired level of consciousness, use of anti-DM medication, glycated hemoglobin levels, and cardioembolic aetiology were independent predictors of a high ABGL. The presence of mismatch or proximal vessel occlusion was not associated with ABPL. Female sex (P = .048) and total anterior circulation stroke (P = .008) were independent predictors associated with a higher ABPL. We conclude that patients with hyperacute ischemic stroke with PWI/DWI mismatch are more likely to have hyperglycemia.

Management of Blood Pressure During and After Recanalization Therapy for Acute Ischemic Stroke

Ischemic stroke is a common neurologic condition and can lead to significant long term disability and death. Observational studies have demonstrated worse outcomes in patients presenting with the extremes of blood pressure as well as with hemodynamic variability. Despite these associations, optimal hemodynamic management in the immediate period of ischemic stroke remains an unresolved issue, particularly in the modern era of revascularization therapies. While guidelines exist for BP thresholds during and after thrombolytic therapy, there is substantially less data to guide management during mechanical thrombectomy. Ideal blood pressure targets after attempted recanalization depend both on the degree of reperfusion achieved as well as the extent of infarction present. Following complete reperfusion, lower blood pressure targets may be warranted to prevent reperfusion injury and promote penumbra recovery however prospective clinical trials addressing this issue are warranted.

Association between Systolic Blood Pressure after Thrombolysis and Early Neurological Improvement in Ischaemic Stroke Patients

Introduction

This study aimed to evaluate the relationship between systolic blood pressures (SBPs) within 12 hours after intravenous recombinant tissue plasminogen activator (rtPA) treatment and early neurological outcomes.

Methods

This was a retrospective observational study of acute ischaemic stroke (AIS) patients who received intravenous rtPA administration. SBPs at the time of rtPA bolus and thereafter every hour were collected. The mean, standard deviation, and coefficient of variation values of SBP during the periods of 0-2 h, 2-6 h, and 6-12 h were calculated. The primary outcome was major neurologic improvement (MNI) at 24 hours after thrombolysis.

Results

Serial measures of SBPs revealed different 12-hour courses between the patients with and without MNI. The difference of SBP tendency was statistically significant (p=0.013). In univariate analysis, patients with MNI showed lower levels of mean SBPs during the periods of 2-6 h and 6-12 h (p=0.030 and p=0.005, respectively), and higher frequency of very early neurologic improvement (VENI) at the end of rtPA infusion (p<0.001). In logistic regression analysis, VENI at 1 h, mean SBP value during 6-12 h, and atrial fibrillation were independently related to MNI at 24 h.

Conclusions

SBP level during the first 12 hours after intravenous rtPA treatment may be an important clinical factor that is associated with early neurological improvement of AIS patients.

Pulse Pressure Within 3 Months After Ischemic Stroke Is Associated With Long-Term Stroke Outcomes

BACKGROUND

Pulse pressure (PP) is a surrogate marker of arterial stiffness. Studies on baseline PP and long-term outcomes in patients with stroke are limited. We aimed to evaluate whether PP within 3 months after ischemic stroke was associated with long-term stroke outcomes.

METHODS

A total of 4,195 patients (61.2 ± 11.6 years, 68.4% men) with first-ever ischemic stroke in 3 months had baseline blood pressure (BP) measured. Study end-points were the combined end-points (recurrent vascular events and all-cause mortality) and recurrent stroke.

RESULTS

In the group <60 years of age, the BP components of systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP), or PP did not significantly correlate with long-term stroke outcomes. In the group ≥60 years of age, PP was significantly associated with combined end-points (hazards ratio [HR] = 1.35; 95% confidence interval [CI], 1.18-1.54) and recurrent stroke (HR = 1.46; 95% CI, 1.24-1.72). Combination of SBP and PP, DBP and PP, or MAP and PP, respectively, showed no incremental value of SBP, DBP, or MAP in predicting long-term stroke outcomes.

CONCLUSIONS

PP was significantly associated with long-term stroke outcomes, and this association was prominent in patients with stroke older than 60 years of age.

Research on the cause of death for severe stroke patients

AIMS AND OBJECTIVES

To explore the characteristics of mortality among severe stroke patients, analyse their causes of death and provide evidence for improving the survival rate of stroke patients.

BACKGROUND

Stroke is an important fatal and disabling disease that poses a large burden on its patients, and its high death rates have caused substantial concern to the World Health Organization.

DESIGN

A retrospective case-control study.

METHODS

A total of 188 patients who died of stroke in the neurological intensive care unit of the First Affiliated Hospital of Chongqing Medical University from January 2012-December 2015 were selected as cases. Additionally, 188 stroke survivors from the same neurological intensive care unit were randomly selected as paired cases. The clinical characteristics of the severe stroke patient deaths were analysed, and a univariate analysis was conducted to determine potential mortality risk factors. A logistic regression analysis was then conducted to determine the independent risk factors of mortality.

RESULTS

We investigated a total of 231 cases of death in neurological intensive care unit patients, 188 of whom died of stroke. Therefore, the death rate from stroke accounted for 81.3% of the total population, with ischaemic, haemorrhagic and mixed strokes accounting for 47.19%, 26.84% and 7.36% of the patients, respectively. The leading cause of death was central nervous system-related causes (central respiratory and circulatory failure, brain herniation), followed by multisystemic causes. The independent risk factors of death among the neurological intensive care unit patients were as follows: brain herniation (OR = 18.15), multiple organ failure (OR = 13.12), dyslipidemia (OR = 4.64), community-acquired lung infection (OR = 4.15), use of mechanical ventilation (OR = 3.37), hypoproteinemia (OR = 2.29), history of hypertension (OR = 2.03) and hospital-acquired pneumonia (OR = 1.75).

CONCLUSIONS

The most common cause of death in stroke patients was damage to the central nervous system. Independent risk factors were brain herniation, multiple organ failure, dyslipidemia, community-acquired lung infection, the use of mechanical ventilation, hypoproteinemia, a history of hypertension and hospital-acquired pneumonia. Clinicians should be aware of the presence and possible effects of these conditions. Early prevention, monitoring and intervention to modify controllable risk factors will improve patient prognosis.

RELEVANCE TO CLINICAL PRACTICE

Clinicians should be aware of the multiple independent risk factors of death and implement timely treatment measures to reduce the incidence of death in severe stroke patients.

Autonomic dysfunction in acute ischemic stroke: an underexplored therapeutic area?

Impaired autonomic function, characterized by a predominance of sympathetic activity, is common in patients with acute ischemic stroke. This review describes methods to measure autonomic dysfunction in stroke patients. It summarizes a potential relationship between ischemic stroke-associated autonomic dysfunction and factors that have been associated with worse outcome, including cardiac complications, blood pressure variability changes, hyperglycemia, immune depression, sleep disordered breathing, thrombotic effects, and malignant edema. Involvement of the insular cortex has been suspected to play an important role in causing sympathovagal imbalance, but its exact role and that of other brain regions remain unclear. Although sympathetic overactivity in patients with ischemic stroke appears to be a negative prognostic factor, it remains to be seen whether therapeutic strategies that reduce sympathetic activity or increase parasympathetic activity might improve outcome.

Blood Pressure and Early Clinical Outcome Among Acute Ischemic Stroke Patients

Objectives:

The association between blood pressure (BP) and short-term clinical outcome of acute ischemic stroke is inconclusive. We investigated the association between BP in the first 72 hours following admission and death in-hospital and neurologic deficiency at discharge among patients with acute ischemic stroke.

Methods:

A total of 2675 acute ischemic stroke patients confirmed by a computed tomography scan or magnetic resonance imaging were included in the present study. Blood pressure in the first 72 hours after admission and other study variables were collected for all ischemic stroke patients. Neurological functions National Institute of Health Stroke Scale (NIHSS) were evaluated by trained neurologists at discharge. The study outcome was defined as death in-hospital and neurologic deficiency (NIHSS≥10) at discharge.

Results:

Systolic and diastolic BP were significantly and positively associated with odds of study outcome in acute ischemic stroke. For example, compared to those with a systolic BP<140 mmHg, multiple-adjusted odds ratio (95% confidence interval) of study outcome was 3.29(1.22, 8.90) among participants with systolic BP of 180-219 mmHg,P<0.05; compared to those with a diastolic BP<90 mmHg, multiple-adjusted odds ratio of study outcome was 7.05(1.32, 37.57) among participants with diastolic BP ≥ 120 mmHg,P<0.05.

Conclusion:

Systolic BP≥180 and diastolic BP≥120 were significantly and positively associated with death in-hospital or neurologic deficiency at discharge among patients with acute ischemic stroke.

Effects of early blood pressure lowering on early and long-term outcomes after acute stroke: an updated meta-analysis

Background

Hypertension is common after acute stroke onset. Previous studies showed controversial effects of early blood pressure (BP) lowering on stroke outcomes. The aim of this study is to assess the effects of early BP lowering on early and long-term outcomes after acute stroke.

Methods

A meta-analysis was conducted with prospective randomized controlled trials assessing the effects of early BP lowering on early and long-term outcomes after acute stroke compared with placebo. Literature searching was performed in the databases from inception to December 2013. New evidence from recent trials were included. Outcomes were analyzed as early (within 30 days) and long-term (from 3 to 12 months) endpoints using summary estimates of relative risks (RR) and their 95% confidence intervals (CI) with the fixed-effect model or random-effect model.

Results

Seventeen trials providing data from 13236 patients were included. Pooled results showed that early BP lowering after acute stroke onset was associated with more death within 30 days compared with placebo (RR: 1.34 and 95% CI: 1.02, 1.74, p = 0.03). However the results showed that early BP lowering had no evident effect on early neurological deterioration, early death within 7 days, long-term death, early and long-term dependency, early and long-term combination of death or dependency, long-term stroke recurrence, long-term myocardial infarction and long-term CVE.

Conclusions

The new results lend no support to early BP lowering after acute stroke. Early BP lowering may increase death within 30 days after acute stroke.

COMBINED ACTION ANTIHYPERTENSIVE AGENT URAPIDIL: EFFECTIVENESS AND SAFETY IN CLINICAL PRACTICE

The paper reviews the clinical practice potential of a combined action antihypertensive medication urapidil for the treatment of patients with acute elevation of blood pressure (BP) and confirms urapidil effectiveness and good tolerability. Urapidil action mechanisms, pharmacodynamics, and pharmacokinetics are discussed, together with the results of the key clinical trials which have demonstrated antihypertensive effectiveness and safety of this agent. Additional beneficial effects of urapidil, such as reduction of the increased pulmonary artery BP and improvement of bronchial conductivity, are also described.

Influence of acute blood pressure on short- and mid-term outcome of ischemic and hemorrhagic stroke

The optimal management of blood pressure (BP) during acute stroke is controversial. We aimed to investigate whether (1) acute BP has differential impact on clinical outcome of ischemic stroke (IS) and spontaneous intracerebral hemorrhage (ICH), and (2) the magnitude of such an effect varies from the very acute phase to the postacute phase of the two diseases. BP values were automatically recorded at 15-min intervals within the first 48 h in consecutive patients with stroke onset less than 24 h before Stroke Unit admission. Growth mixture models were applied to evaluate the association between binary outcome measures [(1) early neurological deterioration (defined as a ≥4-point increase in 48-h National Institutes of Health Stroke Scale [NIHSS] score), (2) 90-day unfavorable functional status (modified Rankin Scale [mRS] 3-6), and (3) 90-day mortality] and the latent heterogeneity of maximum BP trajectories over time, expressed by two (high/low) BP latent classes within stroke groups. After exclusions, 264 patients (198 IS, 66 ICH) were included. High systolic BP (sBP) class was associated with (1) a direct ~15% increased risk of early neurological deterioration [risk difference (RD), +0.151; 95% confidence interval (CI) +0.039 to +0.263] and ~4% worse 48-h outcome for ICH with respect to IS (RD, +0.038; 95% CI +0.005 to +0.071), (2) a ~28% increased risk of 90-day unfavorable outcome in the group of patients with ICH with respect to IS [IRD = RD(ICH) - RD(IS), +0.289; 95% CI +0.010 to +0.571], and (3) no significant effect on 90-day mortality. The influence of acute BP values on mid-term stroke outcome varies depending on the stroke subtype.

Obesity and daytime pulse pressure are predictors of left ventricular hypertrophy in true normotensive individuals

OBJECTIVE

To investigate predictors of left ventricular mass corrected for height2.7 (LVMI) and left ventricular hypertrophy in patients who were found to be normotensive with both office and 24-h ambulatory blood pressure (BP) measurements.

METHODS

A total of 805 consecutive patients were analyzed. All patients underwent office BP measurements, 24-h ambulatory BP monitoring, laboratory measurements for cardiovascular risk factors and echocardiography. Individuals with both office and ambulatory normotension were characterized as true normotensive.

RESULTS

LVMI was found to be 34.5 +/- 10.9 g/m2.7 in normal-weight patients and 48.7 +/- 13.0 g/m2.7 in obese patients (P < 0.0001). LVMI was found to be 41.7 +/- 10 g/m2.7 in overweight patients, significantly lower than the values of obese patients (P < 0.005) and higher than the values of normal-weight patients (P < 0.001). These results remained significant even after adjustment for age, sex, daytime and nighttime SBP, daytime and nighttime DBP, daytime and nighttime BP variability and daytime and nighttime pulse pressure (PP). In a multivariate analysis model, in which LVMI was the dependent variable and office SBP, office DBP, daytime and nighttime SBP and DBP, daytime and nighttime PPs and variabilities, day-night SBP ratio, fasting serum glucose, triglycerides, total cholesterol, age and BMI were inserted as independent variables with weighted least squares regression by sex, the predictors of LVMI were age, BMI and daytime PP (r2 = 0.31). Left ventricular hypertrophy was 17.67 times more likely in obese patients as compared with normal-weight true normotensive individuals.

CONCLUSION

Obesity may represent a significant cardiovascular risk factor even in normotensive individuals. Other predictors of LVMI were ageing and daytime PP.

Acute Blood Pressure Levels and Neurological Deterioration in Different Subtypes of Ischemic Stroke

Background and Purpose— The purpose of this study was to determine at which time points acute blood pressure (BP) was associated with neurological deterioration at 3 weeks in patients with ischemic stroke as a whole and in patients with different subtypes.

Methods— BP was measured every 6 hours for the first 36 hours of emergent hospitalization in 565 consecutive patients (347 men, 70±11 years in age) presenting within 24 hours of an acute ischemic stroke. Neurological deterioration was defined as a ≥2-point increase in the National Institutes of Health stroke scale (NIHSS) score at 3 weeks compared to the admission score.

Results— At 3 weeks, 64 patients (11.3%) had deteriorated neurologically. For the group as a whole, high systolic BP (SBP) values measured at 12, 18, 24, and 36 hours postadmission were independently related to neurological deterioration after adjustment for age, sex, and known predictors, including admission NIHSS score, admission blood glucose level, and large infarct size. At 24 hours, the odds of neurological deterioration increased by 20% per 10-mm Hg increase in SBP. For cardioembolic stroke patients, high SBP values measured at 12 through 36 hours were independently related to neurological deterioration after multivariate adjustment. For patients having stroke other than cardioembolism, no SBP values at any time point were related to neurological deterioration.

Conclusions— Acute SBP values between 12 and 36 hours postadmission, but not those on admission or at 6 hours, were predictive of neurological deterioration within the initial 3 weeks of ischemic stroke, particularly for cardioembolic stroke patients.

Controlling hypertension and hypotension immediately post-stroke (CHHIPS): a randomised, placebo-controlled, double-blind pilot trial

BACKGROUND

Raised blood pressure is common after acute stroke and is associated with an adverse prognosis. We sought to assess the feasibility, safety, and effects of two regimens for lowering blood pressure in patients who have had a stroke.

METHODS

Patients who had cerebral infarction or cerebral haemorrhage and were hypertensive (systolic blood pressure [SBP] >160 mm Hg) were randomly assigned by secure internet central randomisation to receive oral labetalol, lisinopril, or placebo if they were non-dysphagic, or intravenous labetalol, sublingual lisinopril, or placebo if they had dysphagia, within 36 h of symptom onset in this double-blind pilot trial. The doses were titrated up if target blood pressure was not reached. Analysis was by intention to treat. This trial is registered with the National Research Register, number N0484128008.

FINDINGS

179 patients (mean age 74 [SD 11] years; SBP 181 [SD 16] mm Hg; diastolic blood pressure [DBP] 95 [SD 13] mm Hg; median National Institutes of Health stroke scale [NIHSS] score 9 [IQR 5-16] points) were randomly assigned to receive labetolol (n=58), lisinopril (n=58), or placebo (n=63) between January, 2005, and December, 2007. The primary outcome--death or dependency at 2 weeks--occurred in 61% (69) of the active and 59% (35) of the placebo group (relative risk [RR] 1.03, 95% CI 0.80-1.33; p=0.82). There was no evidence of early neurological deterioration with active treatment (RR 1.22, 0.33-4.54; p=0.76) despite the significantly greater fall in SBP within the first 24 h in this group compared with placebo (21 [17-25] mm Hg vs 11 [5-17] mm Hg; p=0.004). No increase in serious adverse events was reported with active treatment (RR 0.91, 0.69-1.12; p=0.50) but 3-month mortality was halved (9.7%vs 20.3%, hazard ratio [HR] 0.40, 95% CI 0.2-1.0; p=0.05).

INTERPRETATION

Labetalol and lisinopril are effective antihypertensive drugs in acute stroke that do not increase serious adverse events. Early lowering of blood pressure with lisinopril and labetalol after acute stroke seems to be a promising approach to reduce mortality and potential disability. However, in view of the small sample size, care must be taken when these results are interpreted and further evaluation in larger trials is needed.

Blood pressure and clinical outcome among patients with acute stroke in Inner Mongolia, China

OBJECTIVES

The association between blood pressure and short-term clinical outcome of acute stroke is inconclusive. We studied the association between admission blood pressure and in-hospital death or disability among acute stroke patients in Inner Mongolia, China.

METHODS

A total of 2178 acute ischemic stroke and 1760 hemorrhagic stroke patients confirmed by a computed tomography scan or magnetic resonance imaging were included in the present study. Blood pressure and other study variables were collected within the first 24 h of hospital admission. Clinical outcomes were evaluated by trained neurologists during hospitalization.

RESULTS

The in-hospital case-fatality rate was higher for acute hemorrhagic stroke (5.9%) than it was for acute ischemic stroke (1.8%), whereas the disability rate was higher for those with acute ischemic stroke (41.3%) than those with acute hemorrhagic stroke (34.4%) at discharge. Blood pressure at admission was not significantly associated with clinical outcome in acute ischemic stroke. On the contrary, systolic and diastolic blood pressures were significantly and positively associated with odds of death or disability in acute hemorrhagic stroke. For example, compared to those with a systolic blood pressure less than 140 mmHg, multiple-adjusted odds ratio (95% confidence interval) of death/disability was 1.38 (0.96, 1.99), 1.42 (1.00, 2.03), 1.84 (1.28, 2.64), and 1.91 (1.35, 2.70) among participants with systolic blood pressure 140-159, 160-179, 180-199, and at least 200 mmHg, respectively (P < 0.0001 for linear trend).

CONCLUSION

Increased systolic and diastolic blood pressure were significantly and positively associated with death and disability among patients with acute hemorrhagic stroke, but not acute ischemic stroke, in Inner Mongolia, China.

Hypertension and hypothyroidism: results from an ambulatory blood pressure monitoring study

OBJECTIVE

To examine differences between hypothyroid patients and healthy volunteers in 24-h ambulatory blood pressure parameters.

METHODS

The study population consisted of 100 individuals who were recently diagnosed for hypothyroidism. These patients had never been treated before with antihypertensive treatment or received drugs for hypothyroidism. All participants underwent 24-h ambulatory blood pressure monitoring. The control group consisted of 100 healthy volunteers matched one to one for gender and age with the hypothyroid participants.

RESULTS

Clinic systolic and diastolic blood pressures were significantly higher in patients with hypothyroidism compared with volunteers. The mean 24-h systolic blood pressure and 24-h pulse pressure were significantly higher in patients with hypothyroidism compared with volunteers. The 24-h systolic blood pressure variability was also significantly higher in patients with hypothyroidism. Fasting serum cholesterol tended to be higher in patients with hypothyroidism compared with volunteers but the difference was not statistically significant, while fasting serum triglycerides were significantly higher. Body mass index was also significantly higher in patients with hypothyroidism.

CONCLUSIONS

These findings indicate that hypothyroidism may be an important predictor of higher mean 24-h systolic blood pressure, 24-h pulse pressure and 24-h systolic blood pressure variability, parameters of ambulatory blood pressure monitoring that have been previously associated with higher cardiovascular target organ damage.

Effect of Nitric Oxide Donors on Blood Pressure and Pulse Pressure in Acute and Subacute Stroke

High blood pressure (BP), pulse pressure (PP), and rate pressure product (RPP) are each associated independently with a poor outcome in acute ischemic stroke. Whereas nitric oxide (NO) donors, such as glyceryl trinitrate (GTN), lower blood pressure in acute ischemic stroke, their effect on other hemodynamic measures is not known. We performed a systematic review of the effects of NO donors on systemic hemodynamic measures in patients with acute/subacute stroke. Randomized controlled trials were identified from searches of the Cochrane Library, Pubmed, and Embase. Information on hemodynamic measures, including systolic BP (SBP), diastolic BP (DBP), and heart rate, were assessed, and hemodynamic derivatives of these were calculated: PP (PP = SBP - DBP), mean arterial pressure (MAP = DBP + PP/3), mid blood pressure (MBP = (SBP + DBP)/2), pulse pressure index (PPI = PP/MAP), and RPP (RPP = SBP x HR). The effect of treatment on hemodynamic measures was calculated as the weighted mean difference (WMD) between treated and control groups with adjustment for baseline. Three trials involving 145 patients were identified; 93 patients received the NO donor, GTN, and 52 patients composed the control group. Compared with placebo, GTN significantly reduced SBP (WMD, -9.80 mm Hg; P < .001), DBP (WMD, -4.43 mm Hg; P < .001), MAP (WMD, - 6.41 mm Hg; P < .001), MBP (WMD, -7.33 mm Hg; P < .001), PP (WMD, -6.11 mm Hg; P < .001), and PPI (WMD, -0.03; P = .04). GTN increased HR (WMD, +3.87 bpm; P < .001) and lowered RPP insignificantly (WMD, -323 mm Hg.bpm; P = .14). Our findings indicate that the NO donor GTN reduces BP, PP, and other derivatives in acute and subacute stroke while increasing HR.

Impact of obesity in intima media thickness of carotid arteries

OBJECTIVE

To explore differences in intima media thickness (IMT) of the carotid arteries induced by differences in BMI.

RESEARCH METHODS AND PROCEDURES

Data from 3173 consecutive subjects, who were referred to our Hypertension Center from 1998 to 2004, were reviewed. Criteria for patients to be considered for further analysis included no past or concurrent antihypertensive medication, no concurrent medication with the potential to raise blood pressure (BP) (e.g., prednisone), and no clinical signs or laboratory evidence of secondary causes of hypertension. Our population was divided into four groups according to NIH criteria for obesity: underweight, normal weight, overweight, and obese. BMI, mean IMT of internal carotid arteries, and 24-hour BP values were available for all subjects. Five hundred thirty six subjects of the four groups, matched for age, gender, and mean 24-hour BP values, were included in the analysis.

RESULTS

Mean IMT of internal carotid arteries was increased with increasing BMI. Mean IMT was significantly higher in obese subjects compared with normal-weight (p < 0.01) and underweight (p < 0.001) subjects. Mean IMT was significantly higher in overweight subjects compared with normal-weight ones (p < 0.05). Furthermore, multivariate regression analysis in obese subjects revealed that fasting serum glucose was independently associated with IMT.

DISCUSSION

Obesity may be an important factor for carotid atherosclerosis, and at least some of the effects of obesity are independent of the BP levels. Fasting serum glucose levels in obese subjects may play an important role in carotid atherosclerosis.

Relationship between outcome and baseline blood pressure and other haemodynamic measures in acute ischaemic stroke: data from the TAIST trial

BACKGROUND

A poor outcome after stroke is associated independently with high blood pressure during the acute phase; however, relationships with other haemodynamic measures [heart rate (HR), pulse pressure (PP), rate-pressure product (RPP)] remain less clear.

METHODS

The Tinzaparin in Acute Ischaemic Stroke Trial is a randomised, controlled trial assessing the safety and efficacy of tinzaparin versus aspirin in 1484 patients with acute ischaemic stroke. Systolic blood pressure (SBP), diastolic blood pressure (DBP) and HR measurements taken immediately prior to randomization were averaged, and the mid-blood pressure (MBP), PP, mean arterial pressure (MAP), pulse pressure index, and RPP were calculated. The relationship between these haemodynamic measures and functional outcome (death or dependency, modified Rankin Scale > 2) and early recurrent stroke, were studied with adjustment for baseline prognostic factors and treatment group. Odds ratios (OR) and 95% confidence intervals (CI) refer to a change in haemodynamic measure by 10 points.

RESULTS

A poor functional outcome was associated with SBP (adjusted OR; 1.11; 95% CI, 1.03-1.21), HR (adjusted OR; 1.15; 95% CI, 1.00-1.31), MBP (adjusted OR; 1.15, 95% CI, 1.03-1.29), PP (adjusted OR; 1.14; 95% CI, 1.02-1.26), MAP (adjusted OR; 1.15; 95% CI, 1.02-1.31) and RPP (adjusted OR; 1.01; 95% CI, 1.00-1.02). Early recurrent stroke was associated with SBP, DBP, MBP and MAP.

CONCLUSIONS

A poor outcome is independently associated with elevations in blood pressure, HR and their derived haemodynamic variables, including PP and the RPP. Agents that modify these measures may improve functional outcome after stroke.

Ambulatory blood pressure monitoring and target organ damage: effects of age and sex

OBJECTIVE

The objective of the present study was to investigate the effect of age and sex in the ambulatory blood pressure measurements, and target organ damage.

METHODS

A total of 1596 patients (50.6% male and 49.4% female), aged 10-87 years, referred to our Hypertension Center for borderline hypertension, underwent 24-h ambulatory blood pressure monitoring, left ventricular echocardiography and measurement of intima-media thickness of carotid arteries.

RESULTS

Adolescent girls had higher mean 24-h and clinic systolic and diastolic blood pressure values than adolescent boys. Men aged 20-60 years had higher mean 24-h and clinic systolic and diastolic blood pressure values than women of the same age. Men older than 60 years had higher mean 24-h systolic and diastolic blood pressure values than women of the same age, but women older than 60 years had higher clinic systolic and diastolic blood pressure values. White-coat effect increased with age in both sexes, but the magnitude of the white-coat effect was higher in women than in men at older ages. Men had higher left ventricular mass corrected for body surface area or height than women in all ages and significantly higher differences in ages between 30 and 80 years. In addition, men had greater carotid intima-media thickness than women in all ages and significantly higher differences in ages between 30 and 80 years.

CONCLUSIONS

Men have greater ambulatory blood pressure values and target organ damage than women of the same age.

Impact of gender on 24-h ambulatory blood pressure and target organ damage

Differences between male and female subjects in mean 24 h blood pressure (BP) values and target organ damage such as left ventricular mass (LVMASS) and intima-media thickness (IMT) of carotid arteries were explained. The study population consisted of 1,445 subjects. All subjects underwent 24 h ambulatory BP monitoring, left ventricular echocardiography and measurement of IMT of carotid arteries. Men and women did not differ in age, body mass index (BMI) and clinic BP values. Mean 24 h systolic and diastolic BP were significantly higher in men compared to women. LVMASS corrected for body surface area or height(2.7), IMT of common (MCCA) and internal (MICA) carotid arteries were found to be significantly higher in men compared to women. Analysis of covariance showed that men had significantly higher LVMASS, MCCA and MICA than women, after adjustment for BMI, age, smoking status, mean 24 h systolic and diastolic BPs, fasting serum glucose, total cholesterol and triglycerides. These findings indicate that male sex could be an important predictor of higher mean 24 h BP and target organ damage for subjects of similar BMI and clinic BP values.

Non-Pharmacological Neuroprotection: Role of Emergency Stroke Management

Acute stroke should be considered a medical emergency, where actions taken in the first hours are fundamental for achieving recovery of the damaged cerebral tissue and a better prognosis for the patient. Recanalization and neuroprotective treatment has been used with mixed results. The effectiveness observed in the first hours with thrombolytic drug treatment is only applicable to a small percentage of patients, and attempts to widen this treatment window have not yet proved fruitful. Pharmacological neuroprotective treatment has not yet demonstrated the clinical effectiveness observed in experimental models. The concept of neuroprotection in cerebral ischemia also involves a series of mechanisms that take place at the cerebral level following vascular occlusion. In this context, it should be borne in mind that a series of physiological functions usually involved in the cerebral metabolism (control of blood pressure, of temperature, of glycemia and of arterial oxygen saturation) play a key role in modulation of the ischemic process. Changes in the control of these mechanisms may aggravate the process of cerebral damage in the first hours of ischemic stroke. In this work we review the prognostic importance of the main mechanisms that may influence the acute phase of cerebral ischemic stroke, as well as their therapeutic management and control in the clinical situation.

Homeostasis as basis of acute stroke treatment: stroke units are the key

INTRODUCTION

Several studies suggest that the control of blood pressure (BP), blood glucose level, body temperature, and oxygen saturation, when analyzed separately, is related with successful acute stroke outcome. However, in a biological system these parameters are interrelated and could influence the process. Recent studies highlight the importance of the appropriate maintenance of these variables that are involved in homeostasis in patients with stroke and the influence they have on outcome.

METHODS

A review was conducted of published studies which analyzed the influence of control of these physiological variables in acute stroke, whether in isolation or combinations, and we have contributed our own data derived from observational studies.

RESULTS

The maintenance of homeostasis forms the basis of acute stroke treatment, in what is termed nonpharmacological neuroprotection. Stroke units (SU) are the ideal environment for this therapeutic approach since their favorable influence on the correct management of BP, body temperature, oxygen saturation, and blood glucose in the progress of stroke patients have been proved.

CONCLUSIONS

The proper management of physiological variables (homeostasis) such as BP, body temperature, blood glucose, and oxygen saturation is the basis of acute stroke treatment, and SU are the key to this approach.

Twenty four hour pulse pressure predicts long term recurrence in acute stroke patients

OBJECTIVES

The impact of different blood pressure (BP) components during the acute stage of stroke on the risk of recurrent stroke is controversial. The present study aimed to investigate by 24 hour BP monitoring a possible association between acute BP values and long term recurrence.

METHODS

A total of 339 consecutive patients with first ever acute stroke underwent 24 hour BP monitoring within 24 hours of ictus. Known stroke risk factors and clinical findings on admission were documented. Patients given antihypertensive medication during BP monitoring were excluded. The outcome of interest during the one year follow up was recurrent stroke. The Cox proportional hazard model was used to analyse association of casual and 24 hour BP recordings with one year recurrence after adjusting for stroke risk factors, baseline clinical characteristics, and secondary prevention therapies.

RESULTS

The cumulative one year recurrence rate was 9.2% (95% CI 5.9% to 12.3%). Multivariate Cox regression analyses revealed age, diabetes mellitus, and 24 hour pulse pressure (PP) as the only significant predictors for stroke recurrence. The relative risk for one year recurrence associated with every 10 mm Hg increase in 24 hour PP was 1.323 (95% CI 1.019 to 1.718, p = 0.036). Higher casual PP levels were significantly related to an increased risk of one year recurrence on univariate analysis, but not in the multivariate Cox regression model.

CONCLUSIONS

Elevated 24 hour PP levels in patients with acute stroke are independently associated with higher risk of long term recurrence. Further research is required to investigate whether the risk of recurrent stroke can be reduced to a greater extent by decreasing the pulsatile component of BP in patients with acute stroke.

Abnormalities in cardiac baroreceptor sensitivity in acute ischaemic stroke patients are related to aortic stiffness

Cardiac BRS (baroreceptor reflex sensitivity) is impaired following ischaemic stroke and predicts the risk of subsequent long-term death and disability. Impaired cardiac BRS may be due to impaired central processing of baroreceptor information following stroke or reduced baroreceptor activity due to increased large artery stiffness. We evaluated the relationship between large (aortic) artery stiffness and cardiac BRS during the acute phase of ischaemic stroke and in comparison with a group of stroke-free control subjects. Thirty-one ischaemic stroke patients were studied within 48 h of onset and again on day 14, along with 26 control subjects free of cerebrovascular disease. Cardiac BRS (determined by spectral analyses) and arterial stiffness estimated by PWVcf (carotid–femoral pulse wave velocity) using applanation tonometry were obtained. At baseline, cardiac BRS was lower in the stroke compared with the control group (4.3±2.3 compared with 6.5±4.2 ms/mmHg; P<0.05). Cardiac BRS values were correlated with PWVcf at <48 h (r=−0.51, P<0.01) and on day 14 (r=−0.54, P<0.01), but not in the control group (r=−0.27, P=not significant). In quantile regression models, taking into account the effect of all cardiovascular variables, cardiac BRS was independently related to PWVcf at baseline and on day 14 in the stroke patients, but stroke was not related to cardiac BRS level when other cardiovascular variables were considered. Wall stiffness of the arterial vessels involved in the baroreflex arc may account for, at least in part, the reduced cardiac BRS observed in acute stroke patients.

Bendrofluazide Fails to Reduce Elevated Blood Pressure Levels in the Immediate Post-Stroke Period

INTRODUCTION

Blood pressure (BP) levels, beat-to-beat blood pressure variability, dynamic cerebral autoregulation and cardiac baroreceptor sensitivity are frequently abnormal following acute stroke and are associated with an adverse short- and long-term prognosis. Thiazide diuretics are effective antihypertensive agents in preventing primary and secondary stroke, but their hypotensive and cerebral autoregulatory effects in the immediate post-stroke period have not been studied.

METHODS

Thirty-seven hypertensive neuroradiologically proven ischaemic stroke patients were randomized in a double-blind, placebo controlled, parallel group study to bendrofluazide 2.5 mg daily or matching placebo, within 96 h of stroke onset, for a 7-day period. Casual and non-invasive beat-to-beat arterial BP levels, cerebral blood flow velocity, ECG and transcutaneous carbon dioxide levels were measured within 70 +/- 20 h of cerebral infarction and again 7 days later. Dynamic cerebral autoregulatory indices, pulse interval, BP variability and cardiac baroreceptor sensitivity were also calculated.

RESULTS

Small, non-significant falls were seen in casual and beat-to-beat BP levels over the 7-day period in both active and placebo-treated patients with no differences between treatments. No significant changes were seen in dynamic cerebral autoregulation or in cardiac baroreceptor sensitivity during the follow-up in either group.

CONCLUSION

Following acute ischaemic stroke, the standard dose of bendrofluazide at 2.5 mg daily in this study sample did not lower systemic BP levels over the subsequent 7-day period. There was no evidence that bendrofluazide significantly altered cerebral autoregulation or improved cardiac baroreceptor sensitivity post-ictus. Bendrofluazide appears to be an ineffective hypotensive agent at the standard dosage in the initial post-stroke period.

Prognostic value of ambulatory and home blood pressures compared with office blood pressure in the general population: follow-up results from the Pressioni Arteriose Monitorate e Loro Associazioni (PAMELA) study

BACKGROUND

Studies in hypertensive patients suggest that ambulatory blood pressure (BP) is prognostically superior to office BP. Much less information is available in the general population, however. Obtaining this information was the purpose of the Pressioni Arteriose Monitorate e Loro Associazioni (PAMELA) study.

METHODS AND RESULTS

Office, home, and 24-hour ambulatory BP values were obtained in 2051 subjects between 25 and 74 years of age who were representative of the general population of Monza (Milan, Italy). Subjects were followed up for an average of 131 months, during which time cardiovascular and noncardiovascular fatal events were recorded (n=186). Office, home, and ambulatory BP values showed a significant exponential direct relationship with risk of cardiovascular or all-cause death. The goodness of fit of the relationship was greater for systolic than for diastolic BP and for night than for day BP, but its overall value was not better for home or ambulatory than for office BP. The slope of the relationship, however, was progressively greater from office to home and ambulatory BP. Home and night BP modestly improved the goodness of fit of the risk model when added to office BP.

CONCLUSIONS

In the PAMELA population, risk of death increased more with a given increase in home or ambulatory than in office BP. The overall ability to predict death, however, was not greater for home and ambulatory than for office BP, although it was somewhat increased by the combination of office and outside-of-office values. Systolic BP was almost invariably superior to diastolic BP, and night BP was superior to day BP.

Impact of obesity on 24-hour ambulatory blood pressure and hypertension

The purpose of the present study was to determine the relationship between body mass index (BMI) and parameters derived from 24-hour ambulatory blood pressure monitoring including mean 24-hour daytime and nighttime systolic and diastolic blood pressures, 24-hour daytime and nighttime pulse pressure, mean 24-hour daytime and nighttime heart rate, dipping and nondipping status. 3216 outpatient subjects who visited our hypertension center and were never treated with antihypertensive medication underwent 24-hour blood pressure monitoring. BMI was significantly correlated with clinic systolic and diastolic blood pressures. Significant correlations were also found between BMI and mean 24-hour daytime and nighttime systolic blood pressure, 24-hour daytime and nighttime pulse pressure, and mean 24-hour daytime and nighttime heart rate. In multivariate regression analysis, clinic systolic, diastolic blood pressure, mean 24-hour systolic blood pressure, 24-hour pulse pressure, and high-density lipoprotein were independently correlated with BMI. The incidence of white coat hypertension was higher in overweight and obese patients than in normal weight subjects. Confirmed ambulatory blood pressure hypertension was also found to be higher in overweight and obese individuals compared with normal weight subjects. Our data also highlight the higher incidence of nondipping status in obesity. These findings suggest that obese patients had increased ambulatory blood pressure parameters and altered circadian blood pressure rhythm with increased prevalence of nondipping status.

COSSACS (Continue or Stop post-Stroke Antihypertensives Collaborative Study): rationale and design

RATIONALE

Up to 40% of acute stroke patients are already taking antihypertensive therapy on hospital admission, and most will develop elevated blood pressure levels as an acute complication of the stroke. However, no clear data exist as to whether antihypertensive therapy should be continued or discontinued in the acute situation. Surveys of clinical practice reveal significant physician variability and no clear guidelines exist.

OBJECTIVES

The primary aim of the Continue or Stop post-Stroke Antihypertensives Collaborative Study (COSSACS) is to assess whether existing antihypertensive therapy should be continued or discontinued within the first 24 h for the first 2 weeks following acute ischaemic and haemorrhagic stroke onset.

DESIGN

COSSACS is a multi-centre, prospective, randomized, open, blinded-endpoint study, in which patients on pre-existing antihypertensive therapy, admitted to hospital within 24 h of onset of suspected stroke, and within 36 h of their last dose of antihypertensive medication, are randomized to continue or stop current antihypertensive therapy.

SETTING

Acute Stroke Units/ Medical Units of at least 25 UK Teaching and District General Hospitals.

PATIENTS

The study will involve 2900 patients with suspected stroke without specific indication to continue or stop their antihypertensive medication in the opinion of their treating clinician.

STUDY OUTCOMES

The primary outcome for COSSACS is the proportion of patients who are dead or dependent (defined by a modified Rankin score > 2) at 14 days post-stroke. Secondary outcomes include blood pressure changes, and neurological and functional status at 2 weeks and 6 months post-ictus.

Salivary cortisol, a biological marker of stress, is positively associated with 24-hour systolic blood pressure in patients with acute ischaemic stroke

BACKGROUND/AIM

The cause of elevated blood pressure (BP) in acute stroke is unknown. Stress is often suggested as a main contributing factor. We aimed to investigate the relationship between BP and stress in patients with acute stroke.

METHODS

58 patients with clinical symptoms of stroke were recruited prospectively after exclusion of haemorrhage by CT scan within 14 h and 15 min (mean) after symptom onset (range 2 h and 45 min-23 h and 40 min). The mean age of the patients was 66 years (range 39-86 years), and the mean National Institute of Health Stroke Scale score was 7 (range 1-26). BP and pulse rate were recorded by non-invasive automatic monitoring hourly for 24 h. Stress was evaluated by testing the level of salivary cortisol. Four samples of saliva were obtained at inclusion, on the evening of the inclusion day (20.00-22.00 h), on the morning of the next day (7.00-9.00 h) and on the afternoon of the inclusion day/next day (15.00-17.00 h) within 24 h after inclusion in the study. Logarithmic transformation was done for cortisol levels.

RESULTS

The 24-hour mean cortisol level (geometric mean 13.6 nmol/l) was related to 24-hour mean systolic BP [SBP; r = 0.36, p = 0.01, multivariate p = 0.02], mean night-time (22.00-6.00 h) SBP (r = 0.43, p = 0.001, multivariate p < 0.005) and mean night-time diastolic BP (r = 0.31, p = 0.02, multivariate p = 0.02). Cortisol levels at inclusion (r = 0.31, p = 0.02, multivariate p = 0.05 for 24-hour SBP) and in the evening were also statistically significantly related to the above BP variables. The morning cortisol (r = 0.28, p = 0.04, multivariate p = 0.04) was related to night-time SBP.

CONCLUSIONS

Salivary cortisol was positively correlated with 24-hour SBP and night-time BP, suggesting that stress is a contributing factor for high BP in acute stroke.

Blood pressure decrease during the acute phase of ischemic stroke is associated with brain injury and poor stroke outcome

BACKGROUND AND PURPOSE

Studies on the relation between blood pressure (BP) and stroke outcome have shown contradictory results. We explored the association of systolic (SBP) and diastolic (DBP) BP during acute stroke with early neurological deterioration, infarct volume, neurological outcome, and mortality at 3 months.

METHODS

We included 304 patients with acute ischemic stroke. SBP and DBP on admission and on the first day were the average values of all readings obtained in the emergency department and during a 24-hour period after patient allocation in the stroke unit.

RESULTS

A U-shaped effect was observed: for every 10 mm Hg <or=180 mm Hg of SBP, the risk of early neurological deterioration, poor outcome, and mortality increased by 6%, 25%, and 7%, respectively, whereas for every 10 mm Hg >180 mm Hg, the risk of early neurological deterioration increased by 40% and the risk of poor outcome increased by 23%, with no effect on mortality. Mean infarct volume increased 7.3 and 5.5 cm(3) for every 10 mm Hg <or=180 and >180 mm Hg. A similar pattern was found in patients with DBP <or=100 or >100 mm Hg. These effects disappeared after adjustment for the use of antihypertensive drugs and BP drop >20 mm Hg within the first day, with the latter being the more important prognostic factor of poor outcome.

CONCLUSIONS

High and low SBP and DBP, as well as a relevant drop in BP, are associated with poor prognosis in patients with ischemic stroke.