Sex differences in perihemorrhagic edema evolution after spontaneous intracerebral hemorrhage

The impact of sex on epidemiology, management, and outcome of spontaneous intracerebral hemorrhage (sICH)

OBJECTIVE

Data on sex differences in spontaneous intracerebral hemorrhages are limited.

METHODS

An automated comprehensive scoping literature review was performed using PubMed and Scopus. Articles written in English about spontaneous intracerebral hemorrhage and sex were reviewed.

RESULTS

Males experience spontaneous intracerebral hemorrhage more frequently than females, at younger ages, and have a higher prevalence of deep bleeds compared to females. Risk factors between sexes vary and may contribute to differing incidences and locations of spontaneous intracranial hemorrhage. Globally, females receive less aggressive care than males, likely impacting survival.

CONCLUSIONS

Epidemiology, risk factors, and treatment of spontaneous intracranial hemorrhage vary by sex, with limited and oftentimes conflicting data available. Further research into the sex-based differences of spontaneous intracranial hemorrhage is necessary for clinicians to better understand how to evaluate and guide treatment in the future.

Sex Differences in Perihematomal Edema Volume and Outcome After Intracerebral Hemorrhage

BACKGROUND

Although larger hematoma volume is associated with worse outcome after intracerebral hemorrhage (ICH), the association between perihematomal edema (PHE) volume and outcome remains uncertain, as does the impact of sex on PHE and outcome. Here we aimed to determine whether larger PHE volume is associated with worse outcome and whether PHE volume trajectories differ by sex.

METHODS

We conducted a post hoc analysis of the Factor VIIa for Acute Hemorrhagic Stroke Treatment (FAST) trial, which randomized patients with ICH to receive recombinant activated factor VIIa or placebo. Computerized planimetry calculated PHE and ICH volumes on serial computed tomography (CT) scans (at baseline [within 3 h of onset], at 24 h, and at 72 h). Generalized estimating equations examined interactions between sex, CT time points, and FAST treatment arm on PHE and ICH volumes. Mixed and multivariable logistic models examined associations between sex, PHE, and outcomes.

RESULTS

A total of 781 patients with supratentorial ICH (mean age 65 years) were included. Compared to women (n = 296), men (n = 485) had similar median ICH (14.9 vs. 13.6 mL, p = 0.053) and PHE volumes (11.1 vs. 10.5 mL, p = 0.56) at baseline but larger ICH and PHE volumes at 24 h (19.0 vs. 14.0 mL, p < 0.001; 22.2 vs. 15.7 mL, p < 0.001) and 72 h (16.0 vs. 11.8 mL, p < 0.001; 28.7 vs. 19.9 mL, p < 0.001). Men had higher absolute early PHE expansion (p < 0.001) and more hematoma expansion (growth ≥ 33% or 6 mL at 24 h, 33% vs. 22%, p < 0.001). An interaction between sex and CT time points on PHE volume (p < 0.001), but not on ICH volume, confirmed a steeper PHE trajectory in men. PHE expansion (per 5 mL, odds radio 1.19, 95% confidence interval 1.10-1.28), but not sex, was associated with poor outcome.

CONCLUSIONS

Early PHE expansion and trajectory in men were significantly higher. PHE expansion was associated with poor outcomes independent of sex. Mechanisms leading to sex differences in PHE trajectories merit further investigation.

Sex differences in perihematomal edema volume and outcome after intracerebral hemorrhage

Objective

To determine whether in patients with intracerebral hemorrhage (ICH) perihematomal edema (PHE) volume trajectories differ by sex.

Methods

We conducted a post-hoc analysis of the Factor-VII-for-Acute-Hemorrhagic-Stroke-Treatment (FAST) trial that randomized patients with ICH to receive recombinant activated Factor VIIa or placebo. Computerized planimetry calculated PHE and ICH volumes on serial CT scans (at baseline [within 3 hours of onset], at 24, and at 72 hours). Generalized estimating equations examined interactions between sex, CT-timepoints, and FAST treatment-arm on PHE and ICH volumes. Mixed and multivariate logistic models examined associations between sex, PHE, and outcomes.

Results

781 with supratentorial ICH (mean age 65 years) were included. Compared to women (n=296), men (n=485) had similar median ICH (14.9 versus 13.6 ml, p=0.053), and PHE volumes (11.1 versus 10.5 ml, p=0.56) at baseline but larger ICH and PHE at 24 hours (19.0 versus 14.0, p<0.001; 22.2 versus 15.7, p<0.001) and 72 hours (16.0 versus 11.8, p<0.001; 28.7 versus 19.9, p<0.001). Men had higher absolute PHE expansion (p<0.001), and more hematoma expansion (growth ≥33% or 6 mL at 24 hours, 33% versus 22%, p<0.001). An interaction between sex and CT-timepoints on PHE (p<0.001) but not on ICH volumes confirmed a steeper PHE trajectory in men. PHE expansion (per 5mL, odds radio, 1.19, 95%-confidence interval 1.10-1.28), but not sex, was associated with poor outcome.

Conclusions

PHE expansion and trajectory in men were significantly higher. PHE expansion was associated with poor outcomes independent of sex. Mechanisms leading to sex differences in PHE trajectories merit further investigation.

What is already known on this topic

Prior research has reported sex differences in intracerebral hemorrhage (ICH) characteristics and some studies suggest worse outcome after ICH in women. However, we do not have a good understanding whether there are sex differences in perihematomal edema (PHE) volume trajectories, or whether sex, independent of confounders, is associated with poor after ICH.

What this study adds

In this post-hoc analysis of 781 patients with supratentorial ICH from the Factor-VII-for-Acute-Hemorrhagic-Stroke-Treatment (FAST) trial in which patients underwent brain CT imaging time-locked to symptom onset (within 3 hours of symptom onset, at 24 hours, and at 72 hours), men compared to women had similar ICH and PHE volumes at baseline, but larger ICH expansion and PHE expansion on follow up imaging. The PHE but not the ICH volume trajectory across scans was significantly higher in men than in women. While PHE expansion was associated with poor outcome at 90 days, outcome between the sexes was similar at 90 days, and sex was not associated with outcome.

How this study might affect research practice or policy

The finding of heightened early PHE and ICH expansion in men may inform study design, patient recruitment strategies, and pre-specification of subgroup analyses in future interventional trials. The findings of this study also suggest that focusing on sex-specific factors may allow novel mechanistic insight into PHE, a major cause of secondary injury and poor outcome after ICH.

Gender Differences in Intracerebral Hemorrhage

Differences exist between genders in intracerebral hemorrhage cause, epidemiology, and outcomes. These gender differences are in part attributable to physiologic differences; however, demographic, social/behavioral risk factors, along with health care system variation and potential family and/or clinician bias play a role as well. These factors vary from region to region and interact, making comprehensive and definitive conclusions regarding sex differences a challenging task. Differences between the genders in intracerebral hemorrhage epidemiology and extensive differences in underlying pathophysiology, intervention, risk factors, and outcome are all discussed.

Spatiotemporal Cofilin Signaling, Microglial Activation, Neuroinflammation, and Cognitive Impairment Following Hemorrhagic Brain Injury

Intracerebral hemorrhage (ICH) is a significant health concern associated with high mortality. Cofilin plays a crucial role in stress conditions, but its signaling following ICH in a longitudinal study is yet to be ascertained. In the present study, we examined the cofilin expression in human ICH autopsy brains. Then, the spatiotemporal cofilin signaling, microglia activation, and neurobehavioral outcomes were investigated in a mouse model of ICH. Human autopsy brain sections from ICH patients showed increased intracellular cofilin localization within microglia in the perihematomal area, possibly associated with microglial activation and morphological changes. Various cohorts of mice were subjected to intrastriatal collagenase injection and sacrificed at time points of 1, 3, 7, 14, 21, and 28 days. Mice suffered from severe neurobehavioral deficits after ICH, lasting for 7 days, followed by a gradual improvement. Mice suffered post-stroke cognitive impairment (PSCI) both acutely and in the chronic phase. Hematoma volume increased from day 1 to 3, whereas ventricle size increased from day 21 to 28. Cofilin protein expression increased in the ipsilateral striatum on days 1 and 3 and then decreased from days 7 to 28. An increase in activated microglia was observed around the hematoma on days 1 to 7, followed by a gradual reduction up to day 28. Around the hematoma, activated microglia showed morphological changes from ramified to amoeboid. mRNA levels of inflammatory [tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β), and interleukin-6 (IL-6) and anti-inflammatory markers [interleukin-10 (IL-10), transforming growth factor-β TGF-β, and arginase I (Arg1)] increased during the acute phase and decreased in the chronic phase. Blood cofilin levels increased on day 3 and matched the increase in chemokine levels. slingshot protein phosphatase 1 (SSH1) protein, which activates cofilin, was increased from day 1 to 7. These results suggest that microglial activation might be the sequel of cofilin overactivation following ICH, leading to widespread neuroinflammation and consequent PSCI.

The association between blood pressure variability and perihematomal edema after spontaneous intracerebral hemorrhage

Background

Perihematomal edema (PHE) after spontaneous intracerebral hemorrhage (sICH) is associated with clinical deterioration, but the etiology of PHE development is only partly understood.

Aims

We aimed to investigate the association between systemic blood pressure (BP) variability (BPV) and formation of PHE.

Methods

From a multicenter prospective observational study, we selected patients with sICH who underwent 3T brain MRI within 21 days after sICH, and had at least 5 BP measurements available in the first week after sICH. Primary outcome was the association between coefficient of variation (CV) of systolic BP (SBP) and edema extension distance (EED) using multivariable linear regression, adjusting for age, sex, ICH volume and timing of the MRI. In addition, we investigated the associations of mean SBP, mean arterial pressure (MAP), their CVs with EED and absolute and relative PHE volume.

Results

We included 92 patients (mean age 64 years; 74% men; median ICH volume 16.8 mL (IQR 6.6–36.0), median PHE volume 22.5 mL (IQR 10.2–41.4). Median time between symptom onset and MRI was 6 days (IQR 4–11), median number of BP measurements was 25 (IQR 18–30). Log-transformed CV of SBP was not associated with EED (B = 0.050, 95%-CI −0.186 to 0.286, p = 0.673). Furthermore, we found no association between mean SBP, mean and CV of MAP and EED, nor between mean SBP, mean MAP or their CVs and absolute or relative PHE.

Discussion

Our results do not support a contributing role for BPV on PHE, suggesting mechanisms other than hydrostatic pressure such as inflammatory processes, may play a more important role.

Brain edema formation and therapy after intracerebral hemorrhage

Intracerebral hemorrhage (ICH) accounts for about 10% of all strokes in the United States of America causing a high degree of disability and mortality. There is initial (primary) brain injury due to the mechanical disruption caused by the hematoma. There is then secondary injury, triggered by the initial injury but also the release of various clot-derived factors (e.g., thrombin and hemoglobin). ICH alters brain fluid homeostasis. Apart from the initial hematoma mass, ICH causes blood-brain barrier disruption and parenchymal cell swelling, which result in brain edema and intracranial hypertension affecting patient prognosis. Reducing brain edema is a critical part of post-ICH care. However, there are limited effective treatment methods for reducing perihematomal cerebral edema and intracranial pressure in ICH. This review discusses the mechanisms underlying perihematomal brain edema formation, the effects of sex and age, as well as how edema is resolved. It examines progress in pharmacotherapy, particularly focusing on drugs which have been or are currently being investigated in clinical trials.

Molecular, Pathological, Clinical, and Therapeutic Aspects of Perihematomal Edema in Different Stages of Intracerebral Hemorrhage

Acute intracerebral hemorrhage (ICH) is a devastating type of stroke worldwide. Neuronal destruction involved in the brain damage process caused by ICH includes a primary injury formed by the mass effect of the hematoma and a secondary injury induced by the degradation products of a blood clot. Additionally, factors in the coagulation cascade and complement activation process also contribute to secondary brain injury by promoting the disruption of the blood-brain barrier and neuronal cell degeneration by enhancing the inflammatory response, oxidative stress, etc. Although treatment options for direct damage are limited, various strategies have been proposed to treat secondary injury post-ICH. Perihematomal edema (PHE) is a potential surrogate marker for secondary injury and may contribute to poor outcomes after ICH. Therefore, it is essential to investigate the underlying pathological mechanism, evolution, and potential therapeutic strategies to treat PHE. Here, we review the pathophysiology and imaging characteristics of PHE at different stages after acute ICH. As illustrated in preclinical and clinical studies, we discussed the merits and limitations of varying PHE quantification protocols, including absolute PHE volume, relative PHE volume, and extension distance calculated with images and other techniques. Importantly, this review summarizes the factors that affect PHE by focusing on traditional variables, the cerebral venous drainage system, and the brain lymphatic drainage system. Finally, to facilitate translational research, we analyze why the relationship between PHE and the functional outcome of ICH is currently controversial. We also emphasize promising therapeutic approaches that modulate multiple targets to alleviate PHE and promote neurologic recovery after acute ICH.

CCL5 Levels Predict Stroke Volume Growth in Acute Ischemic Stroke and Significantly Diminish in Hemorrhagic Stroke Patients

Stroke remains an important health challenge. Here, we study whether circulating chemokine (C-C motif) ligand 5 (CCL5) levels may predict clinical outcomes for stroke patients. A total of 100 consecutive stroke patients (36 acute ischemic and 64 hemorrhagic) were admitted to the stroke unit. Clinical history data and monitoring parameters were recorded. Blood serum was collected at days 0, 1, and hospital discharge to measure CCL5 levels by ELISA. Infarct or hemorrhagic volume, neurological severity (NIHSS), and functional prognosis (mRankin scale) were measured as clinical outcomes. CCL5 levels were lower in patients with hemorrhagic stroke than in patients with acute ischemic stroke. No differences were found between females and males in both types of stroke. Ischemic stroke patients whose infarct volume grew had lower CCL5 levels at day 0. Levels of CCL5 in ischemic and hemorrhagic patients were not associated with more severe symptoms/worse prognosis (NIHSS > 3; mRankin > 2) at admission or at 3 months. CCL5 could be used as a diagnostic marker to distinguish between ischemic and hemorrhagic strokes. Furthermore, CCL5 levels could predict the infarct volume outcomes in ischemic patients.

Perihematomal Edema After Intracerebral Hemorrhage: An Update on Pathogenesis, Risk Factors, and Therapeutic Advances

Intracerebral hemorrhage (ICH) has one of the worst prognoses among patients with stroke. Surgical measures have been adopted to relieve the mass effect of the hematoma, and developing targeted therapy against secondary brain injury (SBI) after ICH is equally essential. Numerous preclinical and clinical studies have demonstrated that perihematomal edema (PHE) is a quantifiable marker of SBI after ICH and is associated with a poor prognosis. Thus, PHE has been considered a promising therapeutic target for ICH. However, the findings derived from existing studies on PHE are disparate and unclear. Therefore, it is necessary to classify, compare, and summarize the existing studies on PHE. In this review, we describe the growth characteristics and relevant underlying mechanism of PHE, analyze the contributions of different risk factors to PHE, present the potential impact of PHE on patient outcomes, and discuss the currently available therapeutic strategies.

Incidence and Outcomes of Hemorrhagic Stroke among Adults in Spain (2016-2018) According to Sex: A Retrospective, Cohort, Observational, Propensity Score Matched Study

(1) Background: We aim to analyze sex differences in the incidence, clinical characteristics and in-hospital outcomes of hemorrhagic stroke (HS) in Spain (2016–2018) using the National Hospital Discharge Database. (2) Methods: Retrospective, cohort, observational study. We estimated the incidence of HS in men and women. We analyzed comorbidity, treatments, procedures, and hospital outcomes. We matched each woman with a man by age, type of HS and medical conditions using propensity score matching. (3) Results: HS was coded in 57,227 patients aged ≥18 years (44.3% women). Overall, men showed higher incidence rates (57.3/10⁵ vs. 43.0/10⁵; p < 0.001; IRR = 1.60; 95% CI: 1.38–1.83). Women suffered more subarachnoid hemorrhages (25.2% vs. 14.6%), whereas men more often had intracerebral hemorrhages (55.7% vs. 54.1%). In-hospital mortality (IHM) was higher for intracerebral hemorrhage in both men and women. Women underwent decompressive craniectomy less often than men (5.0% vs. 6.2%; p < 0.001). After matching, IHM among women was higher (29.0% vs. 23.7%; p < 0.001). Increments in age, comorbidity and use of anticoagulants and antiplatelet agents prior to hospitalization were associated were higher IHM, and decompressive craniectomy was associated with lower IHM in both sexes. After multivariable adjustment, women had higher IHM (OR = 1.23; 95% CI: 1.18–1.28). (4) Conclusion: Men had higher incidence rates of HS than women. Women less often underwent decompressive craniectomy. IHM was higher among women admitted for HS than among men.

Sex Differences in Outcomes After Spontaneous Intracerebral Hemorrhage Among Patients With Low Total Cholesterol Levels

BACKGROUND

Low total cholesterol (TC) levels were shown to be an independent predictor of intracerebral hemorrhagic stroke in previous studies. However, the role of sex in risk and outcome of patients with ICH and low TC levels is unclear. Therefore, the objective of our study was to assess the sex differences in the risk factors and outcomes after spontaneous intracerebral hemorrhage (ICH) in patients with low TC levels in China.

METHODS

This study recruited consecutive patients diagnosed with ICH who were admitted to the Stroke Registry System in Tianjin between May 2005 and May 2018. Patients with low TC levels (defined as TC<200mg/dl) were analyzed in this study. Sex differences in clinical features, risk factors, and outcomes at hospital discharge, 3 months, and 12 months after ICH were evaluated.

RESULTS

Of the 824 patients with low TC levels, 610 men (74%) and 214 women (26%). The mean age at ICH onset was younger in men than in women (60.93±12.54 vs. 64.5±12.28, P<0.001), and men were more likely to have higher educational levels than women. There were higher prevalence rates of hypertension, current smoking status, and alcohol consumption in men. Urinary tract infections were more prevalent in women, and hepatic/renal dysfunctions were more prevalent in men. Women had significantly higher neurological function deficits. With lower Barthel indices (BIs) and higher modified Rankin scale (mRS) scores at admission; but there was no significant difference between men and women in National Institutes of Health Stroke Scale (NIHSS) scores. The study showed that there was no significant difference in mortality and dependency rates at hospital discharge, 3 months, and 12 months after ICH.

CONCLUSIONS

Our study showed that there were no sex differences in clinical outcomes of patients with ICH and low TC levels, which suggests that the effect of low cholesterol as a risk factor for cerebral hemorrhage is the same on patients of different sexs. The possible mechanisms need larger, prospective, multicenter studies to further research.

Sex differences in treatment, radiological features and outcome after intracerebral haemorrhage: Pooled analysis of Intensive Blood Pressure Reduction in Acute Cerebral Haemorrhage trials 1 and 2

Introduction

Reports vary on how sex influences the management and outcome from acute intracerebral haemorrhage. We aimed to quantify sex disparities in clinical characteristics, management, including response to blood pressure lowering treatment, and outcomes in patients with acute intracerebral haemorrhage, through interrogation of two large clinical trial databases.

Patients and Methods

Post-hoc pooled analysis of the Intensive Blood Pressure Reduction in Acute Cerebral Haemorrhage trials 1 and 2, where patients with a hypertensive response (systolic, 150-220 mmHg) after spontaneous intracerebral haemorrhage (<6 h) were randomised to intensive (target <140 mmHg <1 h) or guideline-recommended (<180 mmHg) blood pressure lowering treatment. The interaction of sex on early haematoma growth (24 h), death or major disability (modified Rankin scale scores 3-6 at 90 days), and effect of randomised treatment were determined in multivariable logistic regression models adjusted for baseline confounding variables.

Results

In 3233 participants, 1191 (37%) were women who were significantly older, had higher baseline National Institutes of Health Stroke Scale scores and smaller haematoma volumes compared to men. Men had higher three-month mortality (odds ratio 1.48, 95% confidence interval 1.10-2.00); however, there was no difference between women and men in the combined endpoint of death or major disability. There were no significant sex differences on mean haematoma growth or effect of randomised blood pressure lowering treatment.

Discussion

Men included in the Intensive Blood Pressure Reduction in Acute Cerebral Haemorrhage trials had more comorbidities, larger baseline haematoma volumes and higher mortality after adjustment for age, as compared with women.

Conclusion

Men included in the Intensive Blood Pressure Reduction in Acute Cerebral Haemorrhage trials had a greater odds of dying after intracerebral haemorrhage than women, which could not be readily explained by differing casemix or patterns of blood pressure management.

Clinical trial registration

The Intensive Blood Pressure Reduction in Acute Cerebral Haemorrhage trials studies are registered with ClinicalTrials.gov (NCT00226096 and NCT00716079).

Primary Intraventricular Hemorrhage in Pediatric Patients: Causes, Characteristics, and Outcomes

BACKGROUND

Primary intraventricular hemorrhage (PIVH) is rare, and causes, characteristics, and outcomes remain unknown in children.

METHODS

We retrospectively analyzed the clinical characteristics of patients 1 month to 21 years of age who were admitted to the hospital with PIVH over a 7-year period. PIVH was defined as bleeding confined to the ventricular system without parenchymal or subarachnoid hemorrhage involvement.

RESULTS

Of 18 included patients, 55.6% were female, and mean age was 13.8 ± 6.0 years. The most common presenting symptoms were headache (77.8%) and vomiting (33.3%). In 15 patients (83.3%), known etiologies were diagnosed, including arteriovenous malformations (66.7%), moyamoya disease (11.1%), and aneurysms (5.6%). Idiopathic PIVH was the diagnosis in 3 patients (16.7%). Surgery was performed in 15 patients (83.3%), and 3 patients (16.7%) received conservative treatment. Four patients (28.6%) had an unfavorable outcome at discharge, and 3 patients (16.7%) had an unfavorable outcome at the 3-month follow-up. Higher Graeb score was associated with an unfavorable outcome in both short-term and long-term follow-up.

CONCLUSIONS

Arteriovenous malformations were diagnosed in most pediatric patients with PIVH. Specific surgical treatment of underlying etiologies should be required to increase clinical improvement. Children with a higher Graeb score at admission tended to have poor early and late outcomes.

Stroke in women - from evidence to inequalities

Stroke is the second largest cause of disability-adjusted life-years lost worldwide. The prevalence of stroke in women is predicted to rise rapidly, owing to the increasing average age of the global female population. Vascular risk factors differ between women and men in terms of prevalence, and evidence increasingly supports the clinical importance of sex differences in stroke. The influence of some risk factors for stroke - including diabetes mellitus and atrial fibrillation - are stronger in women, and hypertensive disorders of pregnancy also affect the risk of stroke decades after pregnancy. However, in an era of evidence-based medicine, women are notably under-represented in clinical trials - despite governmental actions highlighting the need to include both men and women in clinical trials - resulting in a reduced generalizability of study results to women. The aim of this Review is to highlight new insights into specificities of stroke in women, to plan future research priorities, and to influence public health policies to decrease the worldwide burden of stroke in women.

Sex Differences in the Clinical Features, Risk Factors, and Outcomes of Intracerebral Hemorrhage: a Large Hospital-based Stroke Registry in China

Intracerebral hemorrhage (ICH) is common in China. However, the sex differences in clinical features, risk factors, and outcomes of ICH remain controversial. Between 2005 and 2014, we recruited patients with primary ICH in Tianjin, China, and evaluated sex differences in clinical features, risk factors, and outcomes at 3, 12, and 36 months after ICH. The 1,325 patients included 897 men (67.7%) and 428 women (32.3%). The mean age at ICH onset was younger among men (59.14 years) than among women (63.12 years, P < 0.001). Men were more likely to have a hematoma in the basal ganglia, while women were more likely to have one in the thalamus. Women had higher frequencies of urinary tract infections, diabetes mellitus, cardiovascular diseases, and obesity. Men had a greater risk of death at 3 months after ICH. However, no sex differences were observed for mortality at 12 and 36 months after ICH or for recurrence and dependency at 3, 12, and 36 months after ICH. These findings suggested that it crucial to strengthen management of AF and complications in patients with ICH, especially management of blood pressure in men for reducing the mortality rates and the burden of ICH in China.

Natural History of Perihematomal Edema and Impact on Outcome After Intracerebral Hemorrhage

BACKGROUND AND PURPOSE

Edema may worsen outcome after intracerebral hemorrhage (ICH). We assessed its natural history, factors influencing growth, and association with outcome.

METHODS

We estimated edema volumes in ICH patients from the Helsinki ICH study using semiautomated planimetry. We assessed the correlation between edema extension distance (EED) and time from ICH onset, creating an edema growth trajectory model up to 3 weeks. We interpolated expected EED at 72 hours and identified clinical and imaging characteristics associated with faster edema growth. Association of EED and mortality was assessed using logistic regression adjusting for predictors of ICH outcome.

RESULTS

From 1013 consecutive patients, 861 were included. There was a strong inverse correlation between EED growth rate (cm/d) and time from onset (days): EED growth=0.162*days exp(-0.927), R²=0.82. Baseline factors associated with larger than expected EED were older age (71 versus 68; P=0.002), higher National Institutes of Health Stroke Scale score (14 versus 8; P<0.001), and lower Glasgow Coma scale score (13 versus 15; P<0.001), larger ICH volume (19.7 versus 12.7 mL; P<0.001), larger initial EED (0.42 versus 0.30; P<0.001), irregularly shaped hematoma (55% versus 42%; P<0.001), and higher glucose (7.6 versus 6.9 mmol/L; P=0.001). Patients with faster edema growth had more midline shift (50% versus 31%; P<0.001), herniation (12% versus 4%; P<0.001), and higher 6-month (46% versus 26%; P<0.001) mortality. In the logistic regression model, higher-than-expected EED was associated with 6-month mortality (odds ratio, 1.60; 95% confidence interval, 1.04-2.46; P=0.032).

CONCLUSIONS

Edema growth can be readily monitored and is an independent determinant of mortality after ICH, providing an important treatment target for strategies to improve patient outcome.

Rate of perihaematomal oedema expansion is associated with poor clinical outcomes in intracerebral haemorrhage

BACKGROUND

Perihaematomal edema (PHE) expansion rate may be a predictor of outcome after intracerebral haemorrhage (ICH). We determined whether PHE expansion rate in the first 72 hours after ICH predicts outcome, and how it compares against other PHE measures.

METHODS

We included patients from the Virtual International Stroke Trials Archive. We calculated PHE expansion rate using the equation: (PHE at 72 hours PHE at baseline)/(time to 72-hour CT scan time to baseline CT scan). Outcomes of interest were mortality and poor 90-day outcome (modified Rankin Scale score of ≥3). Logistic regression was used to assess relationships with outcome.

RESULTS

A total of 596 patients with ICH were included. At baseline, median haematoma volume was 15.0 mL (IQR 7.9-29.2) with median PHE volume of 8.7 mL (IQR 4.5-15.5). Median PHE expansion rate was 0.31 mL/hour (IQR 0.12-0.55). The odds of mortality were greater with increasing PHE expansion rate (OR 2.63, CI 1.10 to 6.25), while the odds of poor outcome also increased with greater PHE growth (OR 1.67, CI 1.28 to 2.39). Female sex had an inverse relationship with PHE growth, but baseline haematoma volume had a direct correlation. Among other PHE measures, only interval increase in PHE correlated with poor outcome. There was no significant difference between the 2 measures of PHE volume expansion.

CONCLUSIONS

Rate of PHE growth over 72 hours was an independent predictor of mortality and poor functional outcomes following ICH. Baseline haematoma volume and gender appear to influence PHE growth.

Comparison of Gender Differences in Intracerebral Hemorrhage in a Multi-Ethnic Asian Population

BACKGROUND

Intracerebral hemorrhage (ICH) accounts for 10-15% of all first time strokes and with incidence twice as high in the Asian compared to Western population. This study aims to investigate gender differences in ICH patient outcomes in a multi-ethnic Asian population.

METHOD

Data for 1,192 patients admitted for ICH were collected over a four-year period. Multivariate logistic regression was used to identify independent predictors and odds ratios were computed for 30-day mortality and Glasgow Outcome Scale (GOS) comparing males and females.

RESULT

Males suffered ICH at a younger age than females (62.2 ± 13.2 years vs. 66.3 ± 15.3 years; P<0.001). The occurrence of ICH was higher among males than females at all ages until 80 years old, beyond which the trend was reversed. Females exhibited increased severity on admission as measured by Glasgow Coma Scale compared to males (10.9 ± 4.03 vs. 11.4 ± 4.04; P = 0.030). No difference was found in 30-day mortality between females and males (F: 30.5% [155/508] vs. M: 27.0% [186/688]), with unadjusted and adjusted odds ratio (F/M) of 1.19 (P = 0.188) and 1.21 (P = 0.300). At discharge, there was a non-statistically significant but potentially clinically relevant morbidity difference between the genders as measured by GOS (dichotomized GOS of 4-5: F: 23.7% [119/503] vs. M: 28.7% [194/677]), with unadjusted and adjusted odds ratio (F/M) of 0.77 (P = 0.055) and 0.87 (P = 0.434).

CONCLUSION

In our multi-ethnic Asian population, males developed ICH at a younger age and were more susceptible to ICH than women at all ages other than the beyond 80-year old age group. In contrast to the Western population, neurological status of female ICH patients at admission was poorer and their 30-day mortality was not reduced. Although the study was not powered to detect significance, female showed a trend toward worse 30-day morbidity at discharge.

Sex-Specific Effects of Progesterone on Early Outcome of Intracerebral Hemorrhage

BACKGROUND

Preclinical evidence suggests that progesterone improves recovery after intracerebral hemorrhage (ICH); however, gonadal hormones have sex-specific effects. Therefore, an experimental model of ICH was used to assess recovery after progesterone administration in male and female rats.

METHODS

ICH was induced in male and female Wistar rats via stereotactic intrastriatal injection of clostridial collagenase (0.5 U). Animals were randomized to receive vehicle or 8 mg/kg progesterone intraperitoneally at 2 h, then subcutaneously at 5, 24, 48, and 72 h after injury. Outcomes included relevant physiology during the first 3 h, hemorrhage and edema evolution over the first 24 h, proinflammatory transcription factor and cytokine regulation at 24 h, rotarod latency and neuroseverity score over the first 7 days, and microglial activation/macrophage recruitment at 7 days after injury.

RESULTS

Rotarod latency (p = 0.001) and neuroseverity score (p = 0.01) were improved in progesterone-treated males, but worsened in progesterone-treated females (p = 0.028 and p = 0.008, respectively). Progesterone decreased cerebral edema (p = 0.04), microglial activation/macrophage recruitment (p < 0.001), and proinflammatory transcription factor phosphorylated nuclear factor-x03BA;B p65 expression (p = 0.0038) in males but not females, independent of tumor necrosis factor-α, interleukin-6, and toll-like receptor-4 expression. Cerebral perfusion was increased in progesterone-treated males at 4 h (p = 0.043) but not 24 h after injury. Hemorrhage volume, arterial blood gases, glucose, and systolic blood pressure were not affected.

CONCLUSIONS

Progesterone administration improved early neurobehavioral recovery and decreased secondary neuroinflammation after ICH in male rats. Paradoxically, progesterone worsened neurobehavioral recovery and did not modify neuroinflammation in female rats. Future work should isolate mechanisms of sex-specific progesterone effects after ICH.

Targeting secondary injury in intracerebral haemorrhage--perihaematomal oedema

Perihaematomal oedema (PHO) is an important pathophysiological marker of secondary injury in intracerebral haemorrhage (ICH). In this Review, we describe a novel method to conceptualize PHO formation within the framework of Starling's principle of movement of fluid across a capillary wall. We consider progression of PHO through three stages, characterized by ionic oedema (stage 1) and progressive vasogenic oedema (stages 2 and 3). In this context, possible modifiers of PHO volume and their value in identifying patients who would benefit from therapies that target secondary injury are discussed; the practicalities of using neuroimaging to measure PHO volume are also considered. We examine whether PHO can be used as a predictor of neurological outcome following ICH, and we provide an overview of emerging therapies. Our discussion emphasizes that PHO has clinical relevance both as a therapeutic target, owing to its augmentation of the mass effect of a haemorrhage, and as a surrogate marker for novel interventions that target secondary injury.

Sex differences in clinical characteristics and outcomes after intracerebral haemorrhage: results from a 12-month prospective stroke registry in Nanjing, China

Background

There is uncertainty surrounding the differences in outcomes after intracerebral haemorrhage (ICH) between men and women. This study aimed to investigate the sex differences in clinical characteristics, severity and outcomes of Chinese ICH patients.

Methods

The Nanjing First Hospital stroke registry was a hospital-based registry of stroke patients with 1-year prospective follow-up. From 2004 to 2008, a total of 651 consecutively recruited patients with acute ICH were enrolled. Primary outcome was death or dependency defined as a modified Rankin Scale score of 3–6 at 12 months. Multivariable logistic regression analyses were performed to determine whether there were sex differences in clinical outcomes after ICH. Clinically important and biologically plausible risk factors of death or dependency were selected from available variables.

Results

A total of 615 ICH patients were enrolled. There was no significant difference in age (63.5 ± 14.0 vs. 62.7 ± 12.7, p = 0.500) between women and men. At baseline, men were more likely to be current smokers (46.1% vs. 3.6%, P < 0.001) or current drinkers (35.4% vs. 3.6%, P < 0.001), but women had higher admission National Institute of Health Stroke Scale (NIHSS) scores than men (10 vs. 8, P = 0.039). Women also had higher rates of death or dependency at 3, 6, and 12 months (61.2% vs. 46.8%, P = 0.001; 56.7% vs. 45.3%, P = 0.009; and 51.8% vs. 44.1%, P = 0.065; respectively). After adjustment for age, existing hypertension and diabetes, prior stroke, previous ischemic heart disease, previous atrial fibrillation, current smoking and alcohol consumption status, pre-stroke dependency, onset-to-door time, admission NIHSS score, admission systolic blood pressure and location of bleeding, the association between the female gender and death or dependency remained statistical significant at 3 months [odds ratio (OR): 1.76; 95% confidence interval (CI): 1.07-2.89], but did not reach statistical significance at 6 months (OR: 1.59; 95% CI: 0.99-2.54) and 12 months (OR: 1.22; 95% CI: 0.77-1.95).

Conclusions

In a Chinese population, women are more likely to be dead or dependent early after ICH than men. However, this gender difference gradually attenuates over the period of 12 months.

Inflammation in intracerebral hemorrhage: from mechanisms to clinical translation

Intracerebral hemorrhage (ICH) accounts for 10-15% of all strokes and is associated with high mortality and morbidity. Currently, no effective medical treatment is available to improve functional outcomes in patients with ICH. Potential therapies targeting secondary brain injury are arousing a great deal of interest in translational studies. Increasing evidence has shown that inflammation is the key contributor of ICH-induced secondary brain injury. Inflammation progresses in response to various stimuli produced after ICH. Hematoma components initiate inflammatory signaling via activation of microglia, subsequently releasing proinflammatory cytokines and chemokines to attract peripheral inflammatory infiltration. Hemoglobin (Hb), heme, and iron released after red blood cell lysis aggravate ICH-induced inflammatory injury. Danger associated molecular patterns such as high mobility group box 1 protein, released from damaged or dead cells, trigger inflammation in the late stage of ICH. Preclinical studies have identified inflammatory signaling pathways that are involved in microglial activation, leukocyte infiltration, toll-like receptor (TLR) activation, and danger associated molecular pattern regulation in ICH. Recent advances in understanding the pathogenesis of ICH-induced inflammatory injury have facilitated the identification of several novel therapeutic targets for the treatment of ICH. This review summarizes recent progress concerning the mechanisms underlying ICH-induced inflammation. We focus on the inflammatory signaling pathways involved in microglial activation and TLR signaling, and explore potential therapeutic interventions by targeting the removal of hematoma components and inhibition of TLR signaling.