The Hydration Influence on the Risk of Stroke (THIRST) Study

Association between blood urea nitrogen to creatinine ratio and 3-month outcome in patients with acute ischaemic stroke: a retrospective cohort study from a large healthcare system

OBJECTIVES

The blood urea nitrogen to creatinine (BUN/Cr) ratio is associated with early neurological deterioration in acute ischaemic stroke (AIS). However, the predictive value of the BUN/Cr ratio for the AIS prognosis remains unclear. Therefore, we evaluated the correlation between the BUN/Cr ratio and the 3-month outcome in patients with AIS, further testing their dose-response relationship.

DESIGN

This retrospective cohort study enrolled patients with AIS who were admitted between 1 January 2013 and 31 May 2022. Poor clinical outcome was defined as 3-month Modified Rankin Scale (mRS) >2. Cox proportional HR was used to evaluate the correlation between the BUN/Cr ratio and 3-month outcome. Restricted cubic spline and robust locally weighted regression analyses were conducted to determine the dose-response relationship between the BUN/Cr ratio and the 3-month outcome.

RESULTS

A total of 4952 eligible patients were included in the study. The patients were divided into three groups according to the tertiles of BUN/Cr ratio (T1, <0.071; T2, 0.071-0.093; and T3, >0.093). After logistic regression adjustment for demographic and clinical characteristics, the BUN/Cr ratio was found to be independently associated with the 3-month outcome in patients with AIS. The restricted cubic spline and locally regression smoothing scatterplot graph showed a strong dose-response relationship between the BUN/Cr ratio and the 3-month outcome in patients with AIS.

CONCLUSION

A dose-response relationship was observed between the BUN/Cr ratio and the 3-month outcome in patients with AIS, suggesting that the BUN/Cr ratio could serve as a reliable predictor for the AIS prognosis.

Association of hydration status and in-hospital mortality in critically ill patients with ischemic stroke: Data from the MIMIC-IV database

BACKGROUND

Hydration plays a critical role in the pathophysiological progression of ischemic stroke. However, the impact of extreme hydration on the mortality of critically ill patients with ischemic stroke remains unclear. Therefore, our objective was to evaluate the association between hydration, as indicated by the blood urea nitrogen to creatinine ratio (UCR), and in-hospital mortality in critically ill patients with ischemic stroke.

METHODS

Data from the Medical Information Mart for Intensive Care (MIMIC-IV) database were utilized. Patients with ischemic stroke admitted to the Intensive Care Unit (ICU) for the first time were identified. The exposure variable was the hydration state represented by the UCR. The study outcome measure was in-hospital mortality. The primary analytical approach involved multivariate Cox regression analysis. Kaplan-Meier curves were constructed, and subgroup analyses with interaction were performed.

RESULTS

A total of 1539 patients, with a mean age of 69.9 years, were included in the study. Kaplan-Meier curves illustrated that patients in higher UCR tertiles exhibited increased in-hospital mortality. Accordingly, the risk of in-hospital mortality significantly rose by 29 % with every 10 units increase in UCR. Subgroup analysis indicated a robust association between UCR and in-hospital mortality in each subgroup, with no statistically significant interactions observed.

CONCLUSION

Hydration status is significantly associated with in-hospital all-cause mortality in critically ill patients with ischemic stroke. This finding underscores the importance of closely monitoring critically ill patients for adequate hydration and implementing appropriate rehydration strategies.

The association between water intake and future cardiometabolic disease outcomes in the Malmö Diet and Cancer cardiovascular cohort

The aim of this study was to explore the longitudinal association between reported baseline water intake and incidence of coronary artery disease (CAD) and type 2 diabetes in the Malmö Diet and Cancer Cohort (n = 25,369). Using cox proportional hazards models, we separately modelled the effect of plain and total (all water, including from food) water on CAD and type 2 diabetes risk, whilst adjusting for age, sex, diet collection method, season, smoking status, alcohol intake, physical activity, education level, energy intake, energy misreporting, body mass index, hypertension, lipid lowering medication, apolipoprotein A, apolipoprotein B, and dietary variables. Sensitivity analyses were run to assess validity. After adjustment, no association was found between tertiles of plain or total water intake and type 2 diabetes risk. For CAD, no association was found comparing moderate to low intake tertiles from plain or total water, however, risk of CAD increased by 12% (95% CI 1.03, 1.21) when comparing high to low intake tertiles of plain water, and by 17% (95% CI 1.07, 1.27) for high versus low tertiles of total water. Sensitivity analyses were largely in agreement. Overall, baseline water intake was not associated with future type 2 diabetes risk, whilst CAD risk was higher with higher water intakes. Our findings are discordant with prevailing literature suggesting higher water intakes should reduce cardiometabolic risk. These findings may be an artefact of limitations within the study, but future research is needed to understand if there is a causal underpinning.

An observational study on salivary conductivity for fluid status assessment and clinical relevance in acute ischemic stroke during intravenous fluid hydration

The body fluid status in acute stroke is a crucial determinant in early stroke recovery but a real-time method to monitor body fluid status is not available. This study aims to evaluate the relationship between salivary conductivity and body fluid status during the period of intravenous fluid hydration. Between June 2020 to August 2022, patients presenting with clinical signs of stroke at the emergency department were enrolled. Salivary conductivities were measured before and 3 h after intravenous hydration. Patients were considered responsive if their salivary conductivities at 3 h decreased by more than 20% compared to their baseline values. Stroke severity was assessed using the National Institutes of Health Stroke Scale, and early neurological improvement was defined as a decrease of ≥ 2 points within 72 h of admission. Among 108 recruited patients, there were 35 of stroke mimics, 6 of transient ischemic attack and 67 of acute ischemic stroke. Salivary conductivity was significantly decreased after hydration in all patients (9008 versus 8118 µs/cm, p = 0.030). Among patients with acute ischemic stroke, the responsive group, showed a higher rate of early neurological improvement within 3 days compared to the non-responsive group (37% versus 10%, p = 0.009). In a multivariate logistic regression model, a decrease in salivary conductivity of 20% or more was found to be an independent factor associated with early neurological improvement (odds ratio 5.42, 95% confidence interval 1.31-22.5, p = 0.020). Real-time salivary conductivity might be a potential indicator of hydration status of the patient with acute ischemic stroke.

Implementing a Screen-Clean-Hydrate bundle of care for improving swallow screening, oral health, and hydration in acute stroke: Protocol for a Type 2 hybrid-effectiveness pre-post study

Stroke clinical guidelines recommend care processes that optimize patient outcomes and minimize hospital-acquired complications. However, audits and surveys illustrate that recommended care is not always consistently or thoroughly implemented. This paper outlines the methods for implementing and evaluating a new bundle of care. Screen-Clean-Hydrate bundles together recommendations from the Australian Clinical Guidelines for Stroke Management and supplements these with evidence-informed best practice from the literature for: swallow screening within 4 h of presentation to hospital (Screen); oral health assessment and delivery of oral care (Clean); and hydration assessment and management (Hydrate). The study is a pre-post Type 2 hybrid effectiveness/implementation design with an embedded process evaluation, which will be conducted in two acute stroke units in a capital city of Australia. The integrated-Promoting Action on Research Implementation in Health Services (iPARIHS) framework will be used to guide study design, conduct, and evaluation. Clinical effectiveness will be measured by rates of hospital-acquired complications and proxy measures of cost (length of stay, procedure costs) for 60 patient participants pre- and postimplementation. Implementation outcomes will focus on acceptability, feasibility, uptake and fidelity, and identification of barriers and enablers to implementation through staff interviews, medical record audits, and researcher field notes. Due to its design as a hybrid effectiveness/implementation study, once completed, the study will provide information on both intervention and implementation effectiveness, including details of successful and unsuccessful multidisciplinary implementation strategies. This will inform a larger multisite effectiveness/implementation trial for future upscale, leading to improved compliance with stroke guidelines and therefore stroke outcomes.

How is hydration assessed and managed in acute stroke? A qualitative study of healthcare staff's knowledge, attitudes and experiences

AIMS AND OBJECTIVES

To explore healthcare staff's experiences of how dehydration is identified and managed in hospitalised patients after acute stroke, and facilitators and challenges to optimising hydration.

BACKGROUND

Optimal hydration post-stroke reduces the risk of neurological deterioration and other complications. Patients are at risk of dehydration in acute stroke, particularly those with dysphagia.

DESIGN

A descriptive qualitative study reported following the COREQ guidelines.

METHODS

Semi-structured interviews, utilising patient vignettes, were conducted in 2018 (Apr-Oct) with a purposive sample of 30 multidisciplinary staff members from two UK stroke units. Interviews were digitally recorded and transcribed verbatim. Content analysis identified common themes which were mapped to the Theoretical Domains Framework and the Behaviour Change Wheel.

RESULTS

The themes were mapped to twelve of the fourteen domains in the Theoretical Domains Framework. Participants believed that inadequate hydration management had potentially serious consequences, and described complex knowledge, skills and cognitive elements to effective hydration care. Participants felt that maintaining hydration was a multidisciplinary responsibility requiring good communication. Although the performance of initial dysphagia screening was reinforced by external audit, other areas of post-stroke hydration management were not; notably, there was no established method of assessing hydration. Barriers to maintaining good hydration included lack of staff, out-of-hours working patterns, low priority given to hydration, patients' comorbidities and complex post-stroke disabilities such as dysphagia, aphasia, inattention and hemiparesis.

CONCLUSION

Findings highlighted the importance of assessing and maintaining hydration but identified barriers to, and variation in, clinical practice. To provide optimal care, barriers to the prevention and treatment of dehydration after stroke must be further understood and addressed.

RELEVANCE TO CLINICAL PRACTICE

Multidisciplinary teamwork is important in hydration care after stroke, but clarity is required about the specific contributions of each team member. Without this, hydration care becomes 'everybody's and nobody's job'.

Stroke Outcome Related to Initial Volume Status and Diuretic Use

Background We hypothesized that stroke outcome is related to multiple baseline hydration-related factors including volume contracted state (VCS) and diuretic use. Methods and Results We analyzed a prospective cohort of subjects with ischemic stroke <24 hours of onset enrolled in acute treatment trials within VISTA (Virtual International Stroke Trials Archive). A VCS was defined based on blood urea nitrogen-to-creatinine ratio. The primary end point was modified Rankin Scale score at 90 days. Primary analysis used generalized ordinal logistic regression over the mRS range, adjusted for Totaled Health Risks in Vascular Events score, onset-to-enrollment time, and thrombolytic use. Of 5971 eligible patients with stroke, 42% were taking diuretics at the time of hospitalization, and 44% were in a VCS. Patients in a VCS were older, had more vascular risk factors, were more likely taking diuretics, and had more severe strokes. Diuretic use was associated with both reduced chance of achieving a good functional outcome (odds ratio [OR], 0.57 [95% CI, 0.52-0.63]) and increased mortality at 90 days (OR, 2.30 [95% CI, 2.04-2.61]). VCS was associated with greater mortality 90 days after stroke (OR, 1.53 [95% CI, 1.33-1.76]). There was no evidence of effect modification among the 3 exposures of VCS, diuretic use, or hypokalemia in relation to outcome. Conclusions A VCS at the time of hospitalization was associated with more severe stroke and odds of death but not associated with worse functional outcome when accounting for relevant characteristics. Diuretic use and low serum potassium at the time of stroke onset were associated with worse outcome and may be worthy of further investigation.

Point-of-Care Saliva Osmolarity Testing for the Screening of Hydration in Older Adults With Hypertension

OBJECTIVES

Older adults have an elevated risk of dehydration, a state with proven detrimental cognitive and physical effects. Furthermore, the use of diuretics by hypertensive patients further compounds this risk. This prospective study investigated the diagnostic accuracy of point-of-care (POC) salivary osmolarity (SOSM) measurement for the detection of dehydration in hypertensive adults with and without diuretic pharmacotherapy.

DESIGN

Prospective diagnostic accuracy study.

SETTING

Home visits to patients recruited from 4 community health centers in West Sulawesi, Indonesia.

PARTICIPANTS

A total of 148 hypertensive older adults (57 men, 91 women). The mean ages of male and female patients were 69.4 ± 11.4 and 68.1 ± 7.8 years, respectively.

METHODS

Hypertensive adults were divided into 2 groups based on the presence of diuretics in their pharmacotherapeutic regimen. First-morning mid-stream urine samples were used to perform urine specific gravity (USG) testing. Same-day SOSM measurements were obtained using a POC saliva testing system.

RESULTS

Both USG (P = .0002) and SOSM (P < .0001) were significantly elevated in hypertensive patients with diuretic pharmacotherapy. At a USG threshold of ≥1.030, 86% of diuretic users were classified as dehydrated compared with 55% of non-using participants. A strong correlation was observed between USG and SOSM measurements (r = 0.78, P < .0001). Using a USG threshold of ≥1.030 as a hydration classifier, an SOSM threshold of ≥93 mOsm had a sensitivity of 78.6% and a specificity of 91.1% for detecting dehydration.

CONCLUSIONS AND IMPLICATIONS

Hypertensive patients on diuretics have significantly higher first-morning USG and SOSM values, indicating a higher likelihood of dehydration relative to those on other classes of antihypertensive medication. POC SOSM assessment correlates strongly with first-morning USG assessment, and represents a rapid and noninvasive alternative to urinary hydration assessment that may be applicable for routine use in populations with elevated risk of dehydration.

Peripheral Organ Injury After Stroke

Stroke is a disease with high incidence, mortality and disability rates. It is also the main cause of adult disability in developed countries. Stroke is often caused by small emboli on the inner wall of the blood vessels supplying the brain, which can lead to arterial embolism, and can also be caused by cerebrovascular or thrombotic bleeding. With the exception of recombinant tissue plasminogen activator (rt-PA), which is a thrombolytic drug used to recanalize the occluded artery, most treatments have been demonstrated to be ineffective. Stroke can also induce peripheral organ damage. Most stroke patients have different degrees of injury to one or more organs, including the lung, heart, kidney, spleen, gastrointestinal tract and so on. In the acute phase of stroke, severe inflammation occurs in the brain, but there is strong immunosuppression in the peripheral organs, which greatly increases the risk of peripheral organ infection and aggravates organ damage. Nonneurological complications of stroke can affect treatment and prognosis, may cause serious short-term and long-term consequences and are associated with prolonged hospitalization and increased mortality. Many of these complications are preventable, and their adverse effects can be effectively mitigated by early detection and appropriate treatment with various medical measures. This article reviews the pathophysiological mechanism, clinical manifestations and treatment of peripheral organ injury after stroke.

Association between Plasma Osmolality and Case Fatality within 1 Year after Severe Acute Ischemic Stroke

PURPOSE

Plasma osmolality, a marker of dehydration, is associated with cardiovascular mortality. We aimed to investigate whether elevated plasma osmolality is associated with case fatality within 1 year after severe acute ischemic stroke.

MATERIALS AND METHODS

We included severe ischemic stroke patients (defined as National Institutes of Health Stroke Scale ≥15 score) within 24 hours from symptom onset admitted to the Department of Neurology, West China Hospital between January 2017 and June 2019. Admission plasma osmolality was calculated using the equation 1.86*(sodium+potassium)+1.15*glucose+urea+14. Elevated plasma osmolality was defined as plasma osmolality >296 mOsm/kg, indicating a state of dehydration. Study outcomes included 3-month and 1-year case fatalities. Multivariable logistic regression was performed to determine independent associations between plasma osmolality and case fatalities at different time points.

RESULTS

A total of 265 patients with severe acute ischemic stroke were included. The mean age was 71.2±13.1 years, with 51.3% being males. Among the included patients, case fatalities were recorded for 31.7% (84/265) at 3 months and 39.6% (105/265) at 1 year. Elevated plasma osmolality (dehydration) was associated with 3-month case fatality [odds ratio (OR) 1.98, 95% confidence interval (CI) 1.07-3.66, p=0.029], but not 1-year case fatality (OR 1.51, 95% CI 0.84-2.72, p=0.165), after full adjustment for confounding factors.

CONCLUSION

Elevated plasma osmolality was independently associated with 3-month case fatality, but not 1-year case fatality, for severe acute ischemic stroke.

Acute Kidney Injury in Acute Ischemic Stroke Patients in Clinical Trials

OBJECTIVES

Acute ischemic stroke patients are at risk of acute kidney injury due to volume depletion, contrast exposure, and preexisting comorbid diseases. We determined the occurrence rate and identified predictors associated with acute kidney injury in acute ischemic stroke patients.

SETTING

Multiple specialized ICUs within academic medical centers.

DESIGN

Post hoc analysis of pooled data from prospective randomized clinical trials.

PATIENTS

Acute ischemic stroke patients recruited within 3 hours or within 5 hours of symptom onset.

INTERVENTIONS

IV recombinant tissue plasminogen activator, endovascular treatment, IV albumin, or placebo.

MEASUREMENTS AND MAIN RESULTS

Serum creatinine levels from baseline and within day 5 or discharge were used to classify acute kidney injury classification into stages. Any increase in serum creatinine was seen in 697 (36.1%) and acute kidney injury was seen in 68 (3.5%) of 1,931 patients with acute ischemic stroke. Severity of acute kidney injury was grade I, II, and III in 3.1%, 0.4%, and 0.05% patients, respectively. Patients with albumin (5.5% compared with 2.6%; p = 0.001), preexisting hypertension (4.3% compared with 1.5%; p = 0.0041), and preexisting renal disease (9.1% compared with 3.0%; p < 0.0001) had higher risk of acute kidney injury. The risk of acute kidney injury was lower between those who either underwent CT angiography (2.0% compared with 4.7%; p = 0.0017) or endovascular treatment (1.6% compared with 4.2%; p = 0.0071). In the multivariate analysis, hypertension (odds ratio, 2.6; 95% CI, 1.2-5.6) and renal disease (odds ratio, 3.5; 95% CI, 1.9-6.5) were associated with acute kidney injury. The risk of death was significantly higher among patients with acute kidney injury (odds ratio, 2.7; 95% CI, 1.4-4.9) after adjusting for age and National Institutes of Health Stroke Scale score strata.

CONCLUSIONS

The occurrence rate of acute kidney injury in acute ischemic stroke patients was low and was not higher in patients who underwent CT angiogram or those who received endovascular treatment. Occurrence of acute kidney injury increased the risk of death within 3 months among acute ischemic stroke patients.

Dehydration in older people: A systematic review of the effects of dehydration on health outcomes, healthcare costs and cognitive performance

OBJECTIVE

To systematically examine the effect of dehydration on health outcomes, identify associated financial costs and consider impacts on cognitive performance in older adults.

DESIGN

A systematic review of English-language articles via OVID using MEDLINE, PsychINFO, EMBASE, and others, to March 2018. Included studies examined the relationship between hydration status and health, care costs or cognitive outcome.

SETTING

Cross sectional and cohort data from studies reporting on dehydration in older adults.

PARTICIPANTS

Adults aged 60 years and older.

MEASUREMENTS

Independent quality ratings were assessed for all extracted articles.

RESULTS

Of 1684 articles screened, 18 papers (N = 33,707) met inclusion criteria. Participants were recruited from hospital settings, medical long-term care centres and the community dwelling population. Data were synthesised using a narrative summary. Mortality rates were higher in dehydrated patients. Furthermore, health outcomes, including frailty, bradyarrhythmia, transient ischemic attacks, oral health and surgery recovery are linked to and worsened by dehydration. Length of hospital stay, either as a principal or secondary diagnosis, is greater in those with dehydration, compared to those who are euhydrated. Finally, neurocognitive functioning may be impacted by dehydration. There are issues with study design, inconsistency in hydration status measurement and different measures used for outcome assessment.

CONCLUSION

Dehydration in older people is associated with increased mortality, poorer course of illness and increased costs for health services. In addition, there is some, but sparse evidence that dehydration in older people is linked to poorer cognitive performance. Intervention studies should test strategies for reducing dehydration in older adults.

A physiological perspective of the associations between hydration status and CTP neuroimaging parameters in hyper-acute ischaemic stroke patients

Hypohydration may be associated with vascular diseases, poor prognosis and worse outcomes in stroke. The underlying mechanisms have not yet been completely investigated, although some studies suggested potential associations with brain perfusion and collaterals status. Despite the potentially different mechanisms promoting serum or urine biomarkers of hypohydration, few studies have investigated both markers separately. A prospective descriptive study was conducted in stroke patients admitted to a stroke unit <4.5 h from symptoms onset. All patients underwent neurological evaluation and whole-brain computed tomography perfusion (CTP) upon admission. Blood and urine samples were immediately collected at admission, and patients were defined as "hypohydrated" (HYP) if blood urea nitrogen-to-creatinine ratio was >15 and "underhydrated" (UND) if urine osmolality was >500 mOsm/kg. CTP images were processed to calculate core, penumbra, their mismatch and total hypoperfused volume. Forty-six patients were included and were grouped according to hydration status. Despite no different NIHSS at baseline, at CTP HYP was independently associated with core-penumbra mismatch (β: -0.157, 95% CI: -0.305 to -0.009; p = .04), while UND was independently associated with the total hypoperfused volume (β: 31.502, 95% CI: 8.522-54.481; p = .01). Using CTP imaging, this study proposes a physiological insight of some possible mechanisms associated with the better outcomes observed in acute stroke patients when properly hydrated. These results suggest different associations between hydration status and CTP parameters depending on serum or urine biomarkers in the hyper-acute phase and encourage the association between hydration status and stroke characteristics.

Seasonal variation in hydration status among community-dwelling elderly in Japan

AIM

While the heat during the summer season may dehydrate the elderly, little is known about the seasonal variation in dehydration. This study aimed to investigate the seasonal variation in hydration status among the community-dwelling elderly in Japan.

METHODS

We retrospectively analyzed the data collected after an overnight fast of adults aged ≥65 years who had no advanced kidney disease and underwent an annual health checkup at Nihon University Hospital between January and December 2019. Participants were classified according to their checkup date, whether summer (n = 265) or not summer (n = 638). The not summer group was subdivided into spring (n = 235), autumn (n = 213) and winter (n = 190).

RESULTS

Among the four seasons, the spring group showed the highest levels of plasma osmolality (306.1 ± 3.9 mOsm/L), urine specific gravity (1.0172 ± 0.0058) and prevalence rates of urine specific gravity ≥1.020 (34.0%). However, seasonal differences were clinically mild, and >90% of participants showed plasma osmolality ≥300 mOsm/L, indicating dehydration, in all four seasons. The summer group showed lower urine specific gravity levels (1.0150 ± 0.0062 vs. 1.0165 ± 0.0064, P < 0.001) and prevalence rates of urine specific gravity ≥1.020 (22.6% vs. 30.4%, P = 0.023) than did the not summer group. The summer season was associated with low urine specific gravity levels even after adjusting for the multiple linear regression model.

CONCLUSION

Japanese elderly after overnight fast are more dehydrated during the spring rather than the summer. Geriatr Gerontol Int 2020; 20: 904-910.

Intersecting vulnerabilities in human biology: Synergistic interactions between climate change and increasing obesity rates

OBJECTIVES

Increasing obesity rates and accelerating climate change represent two global health challenges shaped by lifestyle change and human environmental modifications. Yet, few studies have considered how these issues may interact to exacerbate disease risk.

METHODS

In this theory article, we explore evidence that obesity-related disease and climatic changes share socio-ecological drivers and may interact to increase human morbidity and mortality risks. Additionally, we consider how obesity-climate change interactions may disproportionately affect vulnerable populations and how anthropological research can be applied to address this concern.

RESULTS

Interactions between heat stress and cardiometabolic disease represent an important pathway through which climate change and obesity-related morbidities may jointly impair health. For example, individuals with higher body fatness and obesity-related metabolic conditions (eg, type 2 diabetes) exhibit a reduced ability to dissipate heat. The risk of poor health resulting from these interactions is expected to be heterogeneous, with low- and middle-income countries, individuals of lower socioeconomic status, and minority populations facing a greater disease burden due to relative lack of resource access (eg, air conditioning). Moreover, older adults are at higher risk due to aging-associated changes in body composition and loss of thermoregulation capabilities.

CONCLUSIONS

Few policy makers appear to be considering how interventions can be designed to simultaneously address the medical burden posed by increasing obesity rates and climate change. Anthropological research is well situated to address this need in a nuanced and culturally-sensitive way; producing research that can be used to support community resilience, promote holistic well-being, and improve health outcomes.

Risk of subsequent ischemic stroke in patients with nontyphoidal salmonellosis: A nationwide population-based cohort study

OBJECTIVES

To explore the association between nontyphoidal salmonellosis (NTS) and the risk of acute ischemic stroke (IS) by using a nationwide, population-based study.

METHODS

A retrospective cohort study using claim data from Taiwan's National Health Insurance Research Database (NHIRD), patients aged 18 years and older with histories of NTS (N = 1618) were included from January 1, 2000-December 31, 2012, and the non-NTS group (N = 6472) without NTS were matched by propensity score. The follow-up period was defined as the time from the initial diagnosis of NTS to the date of development of IS, death or 31 December, 2013. Patients previously diagnosed with stroke were excluded. The Cox proportional hazard model with robust sandwich estimator was used to estimate the hazard ratio (HR) and 95% confidence interval (CI) of IS after adjusting for demographic and clinical covariates.

RESULTS

The adjusted hazard ratio (aHR) for the NTS group compared with the non-NTS group was 1.34 (95% confidence interval [CI], 1.10-1.65) for overall stroke. Furthermore, the NTS cohort had an increased risk of IS compared to the non-NTS groups (aHR, 1.42; 95% CI, 1.14-1.78). Stratified analysis showed that compared with propensity score matched non-NTS group, subjects aged ≥65 years, female, those with hypertension, hyperlipidemia, COPD, cancer and heart failure had higher risk of developing stroke. A 1.93-fold significant increase risk for stroke was observed during the first 3-12 months of follow-up (95% CI, 1.07-3.48).

CONCLUSIONS

Patients with NTS is associated with increased risk of developing ischemic stroke compared with non-NTS patients. Timely and mindful treatment plan about NTS may be a milestone to stroke prevention especially in some subpopulation.

Prevalence of hypohydration and its association with stroke severity and independence outcomes in acute ischemic stroke patients

Hypohydration has been suggested increasing the risk of vascular diseases, and it is associated with poor prognosis and worse functional outcome in stroke. Most studies have used blood parameters to determine patients' hydration status. The aim of this study was to measure urine osmolality (uOsm) and its influence on stroke severity and independence. A prospective descriptive study was conducted in stroke patients admitted to a stroke unit. All patients underwent neurological evaluation at admission and discharge using the National Institute of Health Stroke Scale (NIHSS). Independence at discharge was evaluated with the Barthel Index (BI) and the modified Rankin Scale (mRS). uOsm was measured at admission. Patients were grouped in "poor fluid intake" (PF) and "euhydration" (EU), the latter if uOsm ≤ 500 mOsm/kg. Among 119 included patients, the prevalence of PF was 52%, with no difference observed between groups in demographics or blood samples analyses. PF had higher chances of NIHSS > 8 at admission (OR: 4.7 95% CI: 1.3-17.0; p = 0.02), lower BI at discharge (β: -15.3 95% CI: -26.7 to -3.8; p = 0.01), and worse mRS at discharge (OR: 4.01 95% CI: 1.2-14.0; p = 0.02). These findings are consistent with previous results, suggesting that uOsm may be a factor significantly associated with stroke severity and independence outcome after acute ischemic stroke.

Being Conscious of Water Intake Positively Associated with Sufficient Non-Alcohol Drink Intake Regardless of Seasons and Reasons in Healthy Japanese; the KOBE Study: A Cross Sectional Study

The present study sought to clarify if being conscious of water intake (CWI) is associated with sufficient non-alcohol drink (NAD) intake. We used data of healthy participants without diabetes, aged 40–74 years, in the Kobe Orthopedic and Biomedical Epidemiologic (KOBE) study. The association between being CWI and NAD intake was evaluated by multivariate linear regression analyses after adjusting for age, sex, surveyed months (seasons), alcohol drinking, health-awareness life habits, socioeconomic factors, serum osmolarity, estimated daily salt intake, and reasons for NAD intake. Among 988 (698 women and 290 men) participants eligible for the present analyses, 644 participants (65.2%) were CWI and 344 participants (34.8%) were not CWI (non-CWI). The most popular reason for being CWI was to avoid heat stroke in summer and to prevent ischemic cerebral stroke in winter. The CWI group took more NAD, especially decaffeinated beverages, than the non-CWI group (1846.7 ± 675.1 mL/day vs. 1478.0 ± 636.3 ml/day, p < 0.001). There was a significant association between being CWI and NAD intake in multivariate linear regression analyses ever after adjusting for the relevant variables (β = 318.1, p < 0.001). These findings demonstrated CWI, regardless of the reasons and the seasons, was associated with high NAD intake in Japanese healthy population.

Hemoglobin concentration and the risk of hemorrhagic and ischemic stroke in patients undergoing hemodialysis: the Q-cohort study

Background

The contribution of the hemoglobin concentration to the incidence of hemorrhagic or ischemic stroke in patients undergoing hemodialysis is unclear.

Methods

In total, 3436 patients undergoing prevalent hemodialysis were followed up for 4 years. The primary outcome was the first development of hemorrhagic or ischemic stroke. The baseline hemoglobin concentration was divided into quartiles [hemoglobin (g/dL): Q1, ≤9.7; Q2, 9.8-10.5; Q3, 10.6-11.1; Q4, ≥11.2]. The association between the hemoglobin concentration and each type of stroke was examined using the Kaplan-Meier method and a Cox proportional hazards model.

Results

During the follow-up period, 76 (2.2%) patients developed hemorrhagic stroke and 139 (4.0%) developed ischemic stroke. The 4-year incidence rate of hemorrhagic stroke was significantly higher in patients with lower hemoglobin concentrations. Compared with the quartile of patients with the highest hemoglobin concentrations (Q4), the multivariable-adjusted hazard ratios for hemorrhagic stroke were 1.18 (95% confidence interval, 0.56-2.51), 1.59 (0.82-3.21) and 2.31 (1.16-4.73) in patients in Q3, Q2 and Q1, respectively. No association was identified between the 4-year incidence rate of ischemic stroke and the hemoglobin concentration. Compared with the quartile of patients with the lowest hemoglobin concentrations (Q1), the multivariable-adjusted hazard ratios for ischemic stroke were 1.17 (95% confidence interval, 0.73-1.89), 0.88 (0.51-1.51) and 1.10 (0.66-1.83) in patients in Q2, Q3 and Q4, respectively.

Conclusions

Our results suggest that low hemoglobin concentrations are associated with a high risk of hemorrhagic stroke, but not of ischemic stroke, in patients undergoing hemodialysis.

Association between Blood Urea Nitrogen-to-creatinine Ratio and Three-Month Outcome in Patients with Acute Ischemic Stroke

Background:

Hydration status significantly affects the clinical outcome of acute ischemic stroke (AIS) patients. Blood urea nitrogen-to-creatinine ratio (BUN/Cr) is a biomarker of hydration status. However, it is not known whether there is a relationship between BUN/Cr and three-month outcome as assessed by the modified Rankin Scale (mRS) score in AIS patients.

Methods:

AIS patients admitted to West China Hospital from 2012 to 2016 were prospectively and consecutively enrolled and baseline data were collected. Poor clinical outcome was defined as three-month mRS > 2. Univariate and multivariate logistic regression analyses were performed to determine the relationship between BUN/Cr and three-month outcome. Confounding factors were identified by univariate analysis. Stratified logistic regression analysis was performed to identify effect modifiers.

Results:

A total of 1738 patients were included in the study. BUN/Cr showed a positive correlation with the three-month outcome (OR 1.02, 95% CI 1.00-1.03, p=0.04). However, after adjusting for potential confounders, the correlation was no longer significant (p=0.95). An interaction between BUN/Cr and high-density lipoprotein (HDL) was discovered (p=0.03), with a significant correlation between BUN/Cr and three-month outcome in patients with higher HDL (OR 1.03, 95% CI 1.00-1.07, p=0.04).

Conclusion:

Elevated BUN/Cr is associated with poor three-month outcome in AIS patients with high HDL levels.

Management of Blood Pressure After Acute Ischemic Stroke

PURPOSE OF REVIEW

The present manuscript examines the significance of blood pressure elevation in patients with acute ischemic stroke, the physiologic principles worthy of consideration during its treatment, and the recent empirical evidence that should guide management protocols. It also provides a sound and practical approach to treatment along the time continuum, with particular relevance to reperfusion strategies.

RECENT FINDINGS

The existing evidence shows that both insufficient and excessive blood pressures are detrimental to the outcome of patients with acute ischemic stroke. This "U-shaped" relation, however, relates to measurements at the time of presentation, and clinical studies lack detail and specificity relative to differential measurements along the time continuum, particularly prior to and following reperfusion. Extrapolating from recent series, it is possible to construct treatment protocols balanced for effectiveness and safety. The management of blood pressure after acute ischemic stroke is an important, complex, and challenging aspect of care, requiring a thorough understanding of cerebrovascular physiology. Along the time continuum, the therapeutic priorities start with the preservation of penumbral tissue prior to reperfusion and then follow with the limitation of the damaging effects of excessive blood pressure readings after reperfusion, optimizing the chances of improved outcomes.

Effects of Dehydration on Brain Perfusion and Infarct Core After Acute Middle Cerebral Artery Occlusion in Rats: Evidence From High-Field Magnetic Resonance Imaging

Background: Dehydration is common among ischemic stroke patients and is associated with early neurological deterioration and poor outcome. This study aimed to test the hypothesis that dehydration status is associated with decreased cerebral perfusion and aggravation of ischemic brain injury. Methods: Diffusion-weighted imaging and arterial spin labeling perfusion MR imaging were performed on rats with middle cerebral artery occlusion (MCAO) by using a 9.4T MR imaging scanner to measure the volume of infarction and relative cerebral blood flow (rCBF) after infarction. Twenty-five rats were assigned to either a dehydration group or normal hydration group, and dehydration status was achieved by water deprivation for 48 h prior to MCAO. Results: The volume of the infarction was significantly larger for the dehydration group at the 4th h after MCAO (p = 0.040). The progression in the infarct volume between the 1st and 4th h was also larger in the dehydration group (p = 0.021). The average rCBF values of the contralateral normal hemispheres at the 1st and the 4th h were significantly lower in the dehydration group (p = 0.027 and 0.040, respectively). Conclusions: Our findings suggested that dehydration status is associated with the progression of infarct volume and decreases in cerebral blood flow during the acute stage of ischemic stroke. This preliminary study provided an imaging clue that more intensive hydration therapies and reperfusion strategies are necessary for the management of acute ischemic stroke patients with dehydration status.

Aquaporin Membrane Channels in Oxidative Stress, Cell Signaling, and Aging: Recent Advances and Research Trends

Reactive oxygen species (ROS) are produced as a result of aerobic metabolism and as by-products through numerous physiological and biochemical processes. While ROS-dependent modifications are fundamental in transducing intracellular signals controlling pleiotropic functions, imbalanced ROS can cause oxidative damage, eventually leading to many chronic diseases. Moreover, increased ROS and reduced nitric oxide (NO) bioavailability are main key factors in dysfunctions underlying aging, frailty, hypertension, and atherosclerosis. Extensive investigation aims to elucidate the beneficial effects of ROS and NO, providing novel insights into the current medical treatment of oxidative stress-related diseases of high epidemiological impact. This review focuses on emerging topics encompassing the functional involvement of aquaporin channel proteins (AQPs) and membrane transport systems, also allowing permeation of NO and hydrogen peroxide, a major ROS, in oxidative stress physiology and pathophysiology. The most recent advances regarding the modulation exerted by food phytocompounds with antioxidant action on AQPs are also reviewed.

Primary 'dehydration' and acute stroke: a systematic research review

BACKGROUND AND PURPOSE

Hydration status at the time of stroke has been acknowledged as an important determinant in early stroke recovery. However, the diagnosis of dehydration, or more accurately, a volume-contracted state, at the time of stroke is challenging since there are currently no consensus diagnostic criteria. In this systematic review, we gather the available evidence about diagnosis and treatment of dehydration after stroke.

METHODS

Studies of hospitalized ischemic stroke patients that reported rates of dehydration from January 1997 to March 2017 were screened for inclusion via a systematic search of PubMed, CINAHL, Cochrane, and Scopus using keywords hydration, dehydration, hemodilution, viscosity, volume status, and thirst.

RESULTS

Twenty-five studies of 8699 acute stroke patients were included. Nineteen studies reported on the diagnostic approach to dehydration. Findings are synthesized into four main categories of available research including studies that specify: (1) biological mechanisms using animal models to investigate the relationship between dehydration and stroke; (2) measures of dehydration in the acute human stroke population; (3) rehydration therapies after stroke; and (4) outcomes after stroke in dehydrated patients.

CONCLUSIONS

We found considerable variation in terminology specific to hydration status, diagnostic approach to dehydration, and few prospective studies of treatment strategies with varying results. This review supports the need for consensus development of operational diagnostic criteria, standardization of language, and the opportunity for prospective study of rehydration strategies to impact outcome after stroke.

Pilot study of volume contracted state and hospital outcome after stroke

BACKGROUND

An increasing body of research suggests that acute stroke patients who are dehydrated may have worsened functional outcomes. We sought to explore the relationship between a volume contracted state (VCS) at the time of ischemic stroke and hospital outcomes as compared with euvolemic patients.

METHODS

We enrolled a consecutive series of ischemic stroke patients from a single academic stroke center within 12 hours from stroke onset. VCS was defined via surrogate markers (blood urea nitrogen/creatinine ratio >15 and urine specific gravity >1.010). The primary outcome was change in NIH Stroke Scale (NIHSS) score from admission to discharge. Multivariable analyses included adjustment for demographics and infarct size.

RESULTS

Over an 11-month study period, 168 patients were eligible for inclusion. Of the126 with complete laboratory and MRI data, 44% were in a VCS at the time of admission. Demographics were similar in both the VCS and euvolemic groups, as were baseline NIHSS scores (6.7 vs 7.3; p = 0.63) and infarct volumes (12 vs 16 mL; p = 0.48). However, 42% of patients in a VCS demonstrated early clinical worsening, compared with 17% of the euvolemic group (p = 0.02). A VCS remained a significant predictor of worsening NIHSS in adjusted models (odds ratio 4.34; 95% confidence interval 1.75-10.76).

CONCLUSIONS

Acute stroke patients in a VCS demonstrate worse short-term outcomes compared to euvolemic patients, independent of infarct size. Results suggest an opportunity to explore current hydration practices.

Volume of Plasma Expansion and Functional Outcomes in Stroke

BACKGROUND

Plasma expansion in acute ischemic stroke has potential to improve cerebral perfusion, but the long-term effects on functional outcome are mixed in prior trials. The goal of this study was to evaluate how the magnitude of plasma expansion affects neurological recovery in acute stroke.

METHODS

This was a secondary analysis of data from the Albumin in Acute Stroke Part 2 trial investigating the relationship between the magnitude of overall intravenous volume infusion (crystalloid and colloid) to clinical outcome. The data were inclusive of 841 patients with a mean age of 64 years and a median National Institutes of Health Stroke Scale (NIHSS) of 11. In a multivariable-adjusted logistic regression model, this analysis tested the volume of plasma expansion over the first 48 h of hospitalization as a predictor of favorable outcome, defined as either a modified Rankin Scale score of 0 or 1 or a NIHSS score of 0 or 1 at 90 days. This model included all study patients, irrespective of albumin or isotonic saline treatment.

RESULTS

Patients that received higher volumes of plasma expansion more frequently had large vessel ischemic stroke and higher NIHSS scores. The multivariable-adjusted model revealed that there was decreased odds of a favorable outcome for every 250 ml additional volume plasma expansion over the first 48 h (OR 0.91, 95 % CI, 0.88-0.94).

CONCLUSIONS

The present study demonstrates an association between greater volume of plasma expansion and worse neurological recovery.

A randomized controlled study of intravenous fluid in acute ischemic stroke

OBJECTIVE

To compare the outcome of patients with acute ischemic stroke who received or did not receive intravenous fluid.

PATIENTS AND METHODS

This study was a prospective, multicenter, randomized, open-label trial with blinded outcome assessment. We enrolled acute ischemic stroke patients without dehydration aged between 18 and 85 years with NIH Stroke Scale score (NIHSS) score from 1 to 18 who presented within 72h after onset. Patients were randomly assigned to receive 0.9% NaCl solution 100ml/h for 3days or no intravenous fluid.

RESULTS

On the interim unblinded analysis of the safety data, significant excess early neurological deterioration was observed among patients in the non-intravenous fluid group. Therefore, the study was prematurely discontinued after enrollment of 120 patients, mean age 60 years, 56.6% male. Early neurological deterioration (increased NIHSS ≥3 over 72h) not of metabolic or hemorrhagic origin was observed in 15% of the non-IV fluid group and 3.3% of the IV fluid group (p=0.02). Predictors of neurological deterioration were higher NIHSS score, higher plasma glucose, and increased pulse rate. There was no difference in the primary efficacy outcome, NIHSS≤4 at day 7, 83.3% vs 86.7%, p=0.61 or secondary efficacy outcomes.

CONCLUSION

Administration of 0.9% NaCl 100ml/h for 72h in patients with acute ischemic stroke is safe and may be associated with a reduced risk of neurological deterioration. These study findings support the use of intravenous fluid in acute ischemic stroke patients with NIHSS less than 18 who have no contraindications.

[Causal relationships in stroke and kidney injury]

AIM

To assess the frequency, severity, and causes of acute kidney injury (AKI) in patients with stroke.

SUBJECTS AND METHODS

272 patients (143 men and 129 women) (mean age, 66.7±11.6 years) with stroke were examined. The 2008 European Stroke Organization (ESO) guidelines were used to diagnose stroke, to determine indications for and contraindications to thrombolytic therapy, and to evaluate its efficiency. Hemorrhagic and ischemic strokes (HS and IS) were diagnosed in 52 (19%) and 220 (81%) patients, respectively. AKI was diagnosed and classified according to the 2012 Kidney Disease: Improving Global Outcomes (KDIGO) guidelines.

RESULTS

AKI was diagnosed in 89 (33%) patients: 19 (36.5%) with HS and 70 (31.8%) with IS. The relative risk of death in patients with AKI-associated stroke was 2.6 (95% confidence interval (CI) 1.6-4.0). A poor outcome (the combined endpoint of death or Rankin scale scores of 4-5) was noted in 56 (62.9%) patients with AKI and in 70 (38.2 %) without AKI (χ2=14.6; p=0.0002). The relative risk of a poor outcome in patients with AKI-associated with stroke was 1.64 (95% CI 1.3-2.0). Forty-five (50.6%) patients with stroke developed AKI in the prehospital period.

CONCLUSION

AKI complicates stroke in every three patients and increases death rates. 50% of cases develop AKI in the prehospital period due to the common causes of stroke and AKI.

Evaluation of acute kidney injury (AKI) with RIFLE, AKIN, CK, and KDIGO in critically ill trauma patients

PURPOSE

The aim of our study was to evaluate the effects of AKI development on mortality with four different classification systems (RIFLE, AKIN, CK, KDIGO) in critically ill trauma patients followed in the intensive care unit.

METHODS

A retrospective review of 2034 patients in our intensive care unit was conducted between July 2010 and August 2013. A total of 198 patients with primary trauma were included in the study to evaluate the development of AKI.

RESULTS

When the presence of AKI was investigated according to the four criteria (RIFLE, AKIN, CK, and KDIGO), the highest incidence of AKI was found according to the KDIGO classification (74.2%), followed by AKIN (72.2%), RIFLE (69.7%), and CK (59.1%). It was observed that more AKI developed according to KDIGO in patients with multiple trauma and thoracic trauma (p = 0.031, p = 0.029). Sixty-two (31%) of the 198 trauma patients monitored in the intensive care unit died; mortality was frequently found high in AKI stage 2 and 3 patients. According to the CK classification, there was a significant increase in mortality in patients with AKI on the first day (p = 0.045). AKI classifications by RIFLE, AKIN, CK, and KDIGO were independently associated with the risk of in-hospital death.

CONCLUSION

In this study, the presence of AKI was found to be an independent risk factor in the development of in-hospital mortality according to all classification systems (RIFLE, AKIN, CK, and KDIGO) in critically traumatic patients followed in ICU, and the compatibility between RIFLE, AKIN, and KDIGO was the highest among the classification systems.

Dehydration Status is Associated With More Severe Hemispatial Neglect After Stroke

BACKGROUND

Many stroke patients are clinically dehydrated at the time of hospital presentation, which could lead to an increase in blood viscosity and alteration in cerebral perfusion. Impaired cerebral perfusion can cause hemispheric dysfunction, which can be rapidly quantified with bedside tests of hemispatial neglect. We hypothesized that hospitalized patients with laboratory markers consistent with dehydration or a volume contracted state (VCS) would have more severe cerebral dysfunction defined by greater degree of neglect.

METHODS

Subjects were a consecutive series of right-handed patients with acute right hemispheric stroke admitted within the Johns Hopkins Health System. All participants had clinical syndrome and magnetic resonance imaging consistent with acute infarction. The primary definition of a VCS was a urea/creatinine ratio >15, with secondary definition including urine specific gravity over 1.010. Acute infarct volume was measured on magnetic resonance imaging. Neglect was evaluated using a standardized battery of bedside tests.

RESULTS

Of 201 patients meeting inclusion criteria, 131/201 (65%) had elevated BUN/creatinine ratios at admission. Approximately 61% (122/201) had some degree of neglect. Elevated BUN/creatinine ratio was associated with an increased odds of severe neglect in unadjusted models (OR=4.1; 95% CI, 1.2, 14.4), with loss of significance in adjusted models (OR=4.43; 95% CI, 0.99, 19.8) after adjustment for age, infarct volume, sex, and NIHSS score.

CONCLUSIONS

Our data suggest that patients who are in a VCS at the time of stroke may have more frequent and severe neglect, with attenuation of results after adjustment for factors related to stroke size and age. If proven clinically relevant, a formalized rehydration strategy based on objective lab markers may represent an opportunity for improvement in outcome with low-cost, broadly available treatment for acute stroke patients.

Post-traumatic acute kidney injury: a cross-sectional study of trauma patients

BACKGROUND

The causes of post-traumatic acute kidney injury (AKI) are multifactorial, and shock associated with major trauma has been proposed to result in inadequate renal perfusion and subsequent AKI in trauma patients. This study aimed to investigate the true incidence and clinical presentation of post-traumatic AKI in hospitalized adult patients and its association with shock at a Level I trauma center.

METHODS

Detailed data of 78 trauma patients with AKI and 14,504 patients without AKI between January 1, 2009 and December 31, 2014 were retrieved from the Trauma Registry System. Patients with direct renal trauma were excluded from this study. Two-sided Fisher's exact or Pearson's chi-square tests were used to compare categorical data, unpaired Student's t-test was used to analyze normally distributed continuous data, and Mann-Whitney's U test was used to compare non-normally distributed data. Propensity score matching with a 1:1 ratio with logistic regression was used to evaluate the effect of shock on AKI.

RESULTS

Patients with AKI presented with significantly older age, higher incidence rates of pre-existing comorbidities, higher odds of associated injures (subdural hematoma, intracerebral hematoma, intra-abdominal injury, and hepatic injury), and higher injury severity than patients without AKI. In addition, patients with AKI had a longer hospital stay (18.3 days vs. 9.8 days, respectively; P < 0.001) and intensive care unit (ICU) stay (18.8 days vs. 8.6 days, respectively; P < 0. 001), higher proportion of admission into the ICU (57.7% vs. 19.0%, respectively; P < 0.001), and a higher odds ratio (OR) of short-term mortality (OR 39.0; 95% confidence interval, 24.59-61.82; P < 0.001). However, logistic regression analysis of well-matched pairs after propensity score matching did not show a significant influence of shock on the occurrence of AKI.

DISCUSSION

We believe that early and aggressive resuscitation, to avoid prolonged untreated shock, may help to prevent the occurrence of post-traumatic AKI. However, more evidence is required to support this observation.

CONCLUSION

Compared to patients without AKI, patients with AKI presented with different injury characteristics and worse outcome. However, an association between shock and post-traumatic AKI could not be identified.

Favorable outcome of blood urea nitrogen/creatinine-based hydration therapy 3 months after acute ischemic stroke

BACKGROUND

Dehydration is associated with acute ischemic stroke. However, the relationship between hydration therapy given during acute ischemic stroke and clinical outcomes remains unclear.

AIMS

We determined whether hydration therapy in patients with a blood urea nitrogen/creatinine (BUN/Cr) ratio of at least 15 improved clinical outcome.

METHODS

We conducted a nonblinded, phase II, single-arm, prospective study of patients with acute ischemic stroke and BUN/Cr ratio of at least 15 with historical controls. The hydration group received intravenous bolus (300-500 mL) saline followed by maintenance saline infusion (40-80 mL/h for the first 72 hours), whereas the control group received maintenance saline infusion (40-60 mL/h for the first 24 hours and 0-60 mL/h for 24-72 hours after stroke). The study end point was the percentage of patients with a favorable outcome defined as modified Rankin scale score of 2 or lower at 3 months after stroke.

RESULTS

A total of 237 patients were enrolled (hydration, n = 134; control, n = 103). The mean volume of saline infused within the first 72 hours was significantly larger (P < .001), and the rate of favorable outcome at 3 months after stroke was significantly higher (P = .016) in the hydration group than in the controls. Further analysis revealed that the difference was significant in the lacunar stroke subtype (P = .020) but not in the nonlacunar subtype.

CONCLUSIONS

Blood urea nitrogen/Cr ratio-based saline hydration therapy in patients with acute ischemic stroke significantly increased the rate of favorable clinical outcome with functional independence at 3 months after stroke.

Effect of dehydration on the development of collaterals in acute middle cerebral artery occlusion

BACKGROUND AND PURPOSE

Recent large series studies have demonstrated that dehydration is common amongst stroke subjects and is associated with poor outcome. However, the effects of hydration status on the development of collaterals have never been discussed. In this study, the hypothesis that hydration status is an important factor for developing collaterals after acute middle cerebral artery (MCA) infarction was tested.

METHODS

Eighty-seven patients with acute infarction due to occlusion of the MCA were enrolled. Two collateral markers, posterior cerebral artery (PCA) laterality and fluid-attenuated inversion recovery hyperintense vessels (HVs) were assessed from magnetic resonance imaging. Dehydration status was defined by a nitrogen to creatinine ratio ≧ of 15. The associations between dehydration status and the development of collaterals were estimated.

RESULTS

Sixty-one of 87 patients (70.1%) were identified as dehydrated. The development of PCA laterality and HVs shows a significant difference between dehydrated and euhydrated patients. A serum nitrogen to creatinine ratio <15, diastolic blood pressure and the presence of a dense MCA on computed tomography were significantly associated with the development of PCA laterality. A serum nitrogen to creatinine ratio <15, the initial National Institutes of Health Stroke Scale score, the presence of a dense MCA and calcifications of the internal carotid artery on computed tomography were significantly associated with the development of HVs. Dehydration remained an independent negative predictor for the development of PCA laterality and HVs in the multivariate analysis.

CONCLUSIONS

Hydration status is associated with the development of collateral flow after acute MCA occlusion. This preliminary study provides an imaging clue that hydration status and early hydration therapy could be important for acute stroke management.

Fluid Intake Related to Brain Edema in Acute Middle Cerebral Artery Infarction

Evidence of the appropriate amount of fluid intake during the first few days after acute stroke was scarce. Concerns were raised in patients with acute malignant middle cerebral infarction, who tended to have malignant brain edema later. The purpose of the study was to evaluate the effect of fluid intake on the occurrence of malignant brain edema in patients with acute middle cerebral artery infarction. Patients with acute middle cerebral artery infarction who had National Institute of Health Stroke Scale (NIHSS) score of at least 15 were included. Baseline characteristics and amount of fluid intake during the first few days were compared in patients with and without malignant brain edema. One hundred ninety-three patients were studied. Mean NIHSS score was 20. Malignant brain edema occurred in 69 patients (36%). Higher amount of fluid intake (>1650 ml or >28 ml/kg/day or >93% of daily maintenance fluid) showed a significant association with malignant brain edema (OR = 13.86, 95% CI 5.11-37.60, p value <0.001). Decompressive surgery was performed in 35 patients (18%). With mean follow-up of 12 months, 49 patients (49/184, 27%) had favorable outcomes (modified Rankin scale (mRS) 0-2) at final follow-up. Seventy-nine patients (79/184, 43%) died. In the subgroup of patients with malignant brain edema, 39 patients (39/65, 60%) died and only 11% (7/65 patients) had favorable outcome. High amount of fluid intake in the first few days of acute middle cerebral infarction was related to the occurrence of malignant brain edema.

Incidence and predictors of ischemic stroke during hospitalization for congestive heart failure

Heart failure (HF) increases the risk of ischemic stroke. Data regarding the incidence and predictors of ischemic stroke during hospitalization for HF are limited. The study population of this retrospective cohort study consisted of patients with congestive HF, consecutively admitted to our center from October 2010 to April 2014. We excluded patients complicated with acute myocardial infarction, infective endocarditis, and takotsubo cardiomyopathy. We also excluded those with dialysis or mechanical circulatory support. We investigated the incidence of ischemic stroke during hospitalization for HF. Thereafter, we divided the patients without oral anticoagulants at admission into two groups: patients with ischemic stroke and those without it, and explored the predictors of ischemic stroke. A total of 558 patients (287 without atrial fibrillation (AF), 271 with AF) were enrolled. The mean age was 76.8 ± 12.3 years, and 244 patients (44 %) were female. The mean left-ventricular ejection fraction was 47.4 %. Oral anticoagulants were prescribed in 147 patients (8 without AF, 139 with AF). During hospitalization (median length 18 days), symptomatic ischemic stroke (excluding catheter-related) occurred in 15 patients (2.7 % of the total, 8 without AF, 7 with AF). Predictors significantly associated with increased risk of ischemic stroke in patients without oral anticoagulants were as follows; short-term increases in blood urea nitrogen after admission (at day 3; odds ratio (per 1 md/dl): 1.06, 95 % confidence interval (CI) 1.01-1.11, p = 0.02, and at day 7; odds ratio: 1.03, 95 % CI 1.00-1.07, p = 0.03, respectively), and previous stroke (odds ratio; 3.33, 95 % CI 1.01-11.00, p = 0.04). The incidence of ischemic stroke during hospitalization for HF was high, even in patients without AF. Previous stroke and short-term increases in blood urea nitrogen was significantly associated with the incidence of ischemic stroke.

Multiple left ventricular thrombi in a patient with dilated cardiomyopathy and cerebral infarction: a case report

Introduction

It is not clear whether patients with sinus rhythm and reduced left ventricular function should be treated with anticoagulation therapy during or after treatment for heart failure.

Case presentation

A 67-year-old Japanese man was hospitalized at our institution with heart failure due to dilated cardiomyopathy. On day after discharge, he developed cerebral infarction and showed persistence of multiple left ventricular thrombi. His paralysis completely improved at 2 days after edaravone and heparin administration; however, his left visual field defect persisted.

Conclusion

Patients in sinus rhythm with reduced left ventricular function might benefit from anticoagulation therapy during treatment for heart failure.

Water deprivation induces neurovascular and cognitive dysfunction through vasopressin-induced oxidative stress

Adequate hydration is essential for normal brain function and dehydration induces cognitive deterioration. In addition, dehydration has emerged as a stroke risk factor. However, it is unknown whether alterations in cerebrovascular regulation are responsible for these effects. To address this issue, C57Bl/6 mice were water deprived for 24 or 48 hours and somatosensory cortex blood flow was assessed by laser-Doppler flowmetry in a cranial window. Dehydration increased plasma osmolality and vasopressin levels, and suppressed the increase in blood flow induced by neural activity, by the endothelium-dependent vasodilator acetylcholine and the smooth muscle relaxant adenosine. The cerebrovascular dysfunction was associated with oxidative stress and cognitive deficits, assessed using the Y maze. The vasopressin 1a receptor antagonist SR49059 improved the dehydration-induced oxidative stress and vasomotor dysfunction. Dehydration upregulated endothelin-1 in cerebral blood vessels, an effect blocked by SR49059. Furthermore, the endothelin A receptor antagonist BQ123 ameliorated cerebrovascular function. These findings show for the first time that dehydration alters critical mechanisms regulating the cerebral circulation through vasopressin and oxidative stress. The ensuing cerebrovascular dysregulation may alter cognitive function and increase the brain's susceptibility to cerebral ischemia.

The diagnostic accuracy of multi-frequency bioelectrical impedance analysis in diagnosing dehydration after stroke

Background

Non-invasive methods for detecting water-loss dehydration following acute stroke would be clinically useful. We evaluated the diagnostic accuracy of multi-frequency bioelectrical impedance analysis (MF-BIA) against reference standards serum osmolality and osmolarity.

Material/Methods

Patients admitted to an acute stroke unit were recruited. Blood samples for electrolytes and osmolality were taken within 20 minutes of MF-BIA. Total body water (TBW%), intracellular (ICW%) and extracellular water (ECW%), as percentages of total body weight, were calculated by MF-BIA equipment and from impedance measures using published equations for older people. These were compared to hydration status (based on serum osmolality and calculated osmolarity). The most promising Receiver Operating Characteristics curves were plotted.

Results

27 stroke patients were recruited (mean age 71.3, SD10.7). Only a TBW% cut-off at 46% was consistent with current dehydration (serum osmolality >300 mOsm/kg) and TBW% at 47% impending dehydration (calculated osmolarity ≥295–300 mOsm/L) with sensitivity and specificity both >60%. Even here diagnostic accuracy of MF-BIA was poor, a third of those with dehydration were wrongly classified as hydrated and a third classified as dehydrated were well hydrated. Secondary analyses assessing diagnostic accuracy of TBW% for men and women separately, and using TBW as a percentage of lean body mass showed some promise, but did not provide diagnostically accurate measures across the population.

Conclusions

MF-BIA appears ineffective at diagnosing water-loss dehydration after stroke and cannot be recommended as a test for dehydration, but separating assessment by sex, and using TBW as a percentage of lean body weight may warrant further investigation.

Guidelines for the early management of patients with acute ischemic stroke: a guideline for healthcare professionals from the American Heart Association/American Stroke Association

BACKGROUND AND PURPOSE

The authors present an overview of the current evidence and management recommendations for evaluation and treatment of adults with acute ischemic stroke. The intended audiences are prehospital care providers, physicians, allied health professionals, and hospital administrators responsible for the care of acute ischemic stroke patients within the first 48 hours from stroke onset. These guidelines supersede the prior 2007 guidelines and 2009 updates.

METHODS

Members of the writing committee were appointed by the American Stroke Association Stroke Council's Scientific Statement Oversight Committee, representing various areas of medical expertise. Strict adherence to the American Heart Association conflict of interest policy was maintained throughout the consensus process. Panel members were assigned topics relevant to their areas of expertise, reviewed the stroke literature with emphasis on publications since the prior guidelines, and drafted recommendations in accordance with the American Heart Association Stroke Council's Level of Evidence grading algorithm.

RESULTS

The goal of these guidelines is to limit the morbidity and mortality associated with stroke. The guidelines support the overarching concept of stroke systems of care and detail aspects of stroke care from patient recognition; emergency medical services activation, transport, and triage; through the initial hours in the emergency department and stroke unit. The guideline discusses early stroke evaluation and general medical care, as well as ischemic stroke, specific interventions such as reperfusion strategies, and general physiological optimization for cerebral resuscitation.

CONCLUSIONS

Because many of the recommendations are based on limited data, additional research on treatment of acute ischemic stroke remains urgently needed.

Recommendations for healthier hydration: addressing the public health issues of obesity and type 2 diabetes

Given the rapid increase in the prevalence of overweight, obesity, type 2 diabetes and other obesity-related conditions across the world, despite a plethora of evidence-based guidance for clinicians, innovative campaigns aimed at the general public and widespread government public health initiatives, it is clear that a novel approach is required. The importance of fluid intake has been overlooked in campaigns and guidelines and also in the clinical setting, where the question 'what do you drink?' is often omitted. It is a significant oversight that food pyramids and healthy-eating plates across the world omit fluids from their graphics and advice. While guidelines include recommendations on changes in physical activity and diet, often little or no advice is offered on the importance of healthier hydration practices, neglecting to highlight the contribution of beverages high in sugar, alcohol or additives. An interdisciplinary group of experts in medicine, nutrition, physiology and public health discussed issues surrounding healthy-hydration practices in March 2010 in Paris to create a consensus statement on hydration and gain of body weight and provide recommendations.