Cognitive outcome after aneurysmal subarachnoid hemorrhage: time course of recovery and relationship to clinical, radiological, and management parameters

TREM2 alleviates long-term cognitive dysfunction after subarachnoid hemorrhage in mice by attenuating hippocampal neuroinflammation via PI3K/Akt signaling pathway

Subarachnoid hemorrhage (SAH) often leads to long-term cognitive deficits in patients, particularly due to injury to brain regions such as the hippocampus. This study aims to investigate the role of the triggering receptor expressed on myeloid cells 2 (TREM2) in mitigating hippocampal injury and associated cognitive impairments following SAH. To explore the protective effects of TREM2, we utilized the TREM2 agonist COG1410 to upregulate TREM2 expression and employed TREM2 knockout (KO) mice to verify the necessity of TREM2 for this protective role. The study further examined the involvement of the PI3K/Akt signaling pathway in TREM2-mediated neuroprotection. Our findings indicate that the upregulation of TREM2 significantly alleviated long-term cognitive deficits and promoted the recovery of hippocampal neural activity post-SAH. The neuroprotective effects were linked to reduced microglial activation and decreased secretion of inflammatory factors within the hippocampus. In contrast, TREM2 KO mice did not exhibit these protective effects. Furthermore, inhibition of the PI3K/Akt pathway also diminished these protective effects of TREM2 upregulation and worsened cognitive outcomes. In conclusion, TREM2 upregulation mitigates long-term cognitive dysfunction following SAH by attenuating hippocampal neuroinflammation via the PI3K/Akt signaling pathway. These findings suggest that TREM2 could be a potential therapeutic target for improving cognitive outcomes after SAH.

Exosomes in Vascular/Neurological Disorders and the Road Ahead

Neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), Huntington's disease (HD), stroke, and aneurysms, are characterized by the abnormal accumulation and aggregation of disease-causing proteins in the brain and spinal cord. Recent research suggests that proteins linked to these conditions can be secreted and transferred among cells using exosomes. The transmission of abnormal protein buildup and the gradual degeneration in the brains of impacted individuals might be supported by these exosomes. Furthermore, it has been reported that neuroprotective functions can also be attributed to exosomes in neurodegenerative diseases. The potential neuroprotective functions may play a role in preventing the formation of aggregates and abnormal accumulation of proteins associated with the disease. The present review summarizes the roles of exosomes in neurodegenerative diseases as well as elucidating their therapeutic potential in AD, PD, ALS, HD, stroke, and aneurysms. By elucidating these two aspects of exosomes, valuable insights into potential therapeutic targets for treating neurodegenerative diseases may be provided.

Cognitive outcomes following aneurysmal subarachnoid hemorrhage: Rehabilitation strategies

Despite decreases in mortality rate, the treatment of cognitive deficits following aneurysmal subarachnoid hemorrhage (aSAH) remains a serious challenge for clinicians and survivors alike. Deficits in executive function, language, and memory prevent more than half of survivors from returning to their previous level of work and put a tremendous amount of stress on the individual and their family. New therapies are needed for survivors of aSAH in order to improve cognitive outcomes and quality of life. The aim of this review is to discuss the prevalence and contributing factors of cognitive deficits following aSAH, as well as areas for therapeutic intervention. Due to the limited research on cognitive rehabilitative strategies for aSAH, a literature search of traumatic brain injury (TBI) was used to explore therapies with the potential to improve cognitive outcomes in aSAH. Across cognitive domains, existing rehabilitative and pharmacotherapeutic strategies for TBI show promise to be useful for survivors of aSAH. However, further study of these therapies in addition to consistent assessment of cognitive deficits are required to determine their efficacy in survivors of aSAH.

Long-term Course of Cognitive Functioning After Aneurysmal and Angiographically Negative Subarachnoid Hemorrhage

BACKGROUND AND OBJECTIVES

Cognitive impairment is a common consequence of subarachnoid hemorrhage (SAH), negatively affecting everyday functioning. This study is the first to investigate the long-term course of cognitive functioning after SAH and its associations with long-term well-being (ie, anxiety and depression), cognitive complaints, and return to work, separately for patients with aneurysmal SAH (aSAH) and angiographically negative SAH (anSAH) in a longitudinal design.

METHODS

Cognitive functioning was measured at 2 time points (T1: 3-6 months post-SAH; T2: 2-4 years post-SAH) in 58 patients with aSAH and 22 patients with anSAH with neuropsychological tests for (working) memory, psychomotor speed, and attention/executive functioning. Questionnaires were used to measure cognitive complaints and well-being at T1 and T2 and return to work at T2.

RESULTS

At T2, patients with aSAH only showed improvements in memory and on an executive functioning and psychomotor speed subtest, whereas in contrast, patients with anSAH had significantly poorer scores on tests for psychomotor speed. A significant amount of patients with aSAH and anSAH still reported cognitive complaints, anxiety, and depression in the chronic stage. Cognitive functioning was not significantly associated with cognitive complaints in both SAH groups. On the other hand, cognitive complaints were related to well-being at the long-term in both SAH groups. More cognitive complaints were also associated with more difficulties in return to work in patients with aSAH.

CONCLUSION

Patients with aSAH and anSAH have cognitive impairments at the subacute stage post-SAH, and these impairments persist into the chronic stage. Moreover, both SAH groups still reported decreased well-being in the chronic stage post-SAH, related to cognitive complaints but not to cognitive impairment. For clinical practice, an early neuropsychological assessment will already provide relevant information to estimate long-term cognitive impairment, but in addition, it is important to pay attention to psychological distress at the long-term.

Investigating Recovery After Subarachnoid Hemorrhage With the Imaging, Cognition and Outcome of Neuropsychological Functioning After Subarachnoid Hemorrhage (ICONS) Study: Protocol for a Longitudinal, Prospective Cohort Study

Background

A subarachnoid hemorrhage is a hemorrhage in the subarachnoid space that is often caused by the rupture of an aneurysm. Patients who survive a subarachnoid hemorrhage have a high risk of complications and a negative long-term outcome.

Objective

The aim of the Imaging, Cognition and Outcome of Neuropsychological functioning after Subarachnoid hemorrhage (ICONS) study is to investigate whether and to what extent deficits exist in multiple domains after subarachnoid hemorrhage, including cognition, emotion and behavior, and to investigate whether brain damage can be detected in patients with subarachnoid hemorrhage. We aim to determine which early measures of cognition, emotion and behavior, and brain damage in the subacute stage play a role in long-term recovery after subarachnoid hemorrhage. Recovery is defined as functioning at a societal participation level, with a focus on resuming and maintaining work, leisure activities, and social relationships over the long term.

Methods

The ICONS study is an observational, prospective, single-center cohort study. The study includes patients with subarachnoid hemorrhage admitted to the Neurosurgery Unit of the University Medical Centre Groningen in the Netherlands. The inclusion criteria include diagnosis of an aneurysmal subarachnoid hemorrhage or an angiographically negative subarachnoid hemorrhage, sufficient ability in the Dutch language, and age older than 18 years. Patients will undergo neuropsychological assessment and magnetic resonance imaging 6 months after the subarachnoid hemorrhage. Furthermore, patients will be asked to fill in questionnaires on multiple psychosocial measures and undergo a structured interview at 6 months, 1 year, and 2 years after the subarachnoid hemorrhage. The primary outcome measure of the ICONS study is societal participation 1 year after the subarachnoid hemorrhage, measured with the Dutch version of the Impact on Participation and Autonomy questionnaire.

Results

The study was launched in December 2019 and recruitment is expected to continue until June 2023. At the time of the acceptance of this paper, 76 patients and 69 healthy controls have been included. The first results are expected in early 2023.

Conclusions

The ICONS study is the first to collect and combine data after subarachnoid hemorrhage in a variety of domains, including cognition, emotion and behavior, and brain damage. The results will contribute to a more comprehensive understanding of the consequences of both aneurysmal subarachnoid hemorrhage and angiographically negative subarachnoid hemorrhage, which may ultimately optimize timely treatment for this patient group by setting realistic and attainable goals to improve daily functioning.

Trial Registration

Netherlands Trial Register NL7803; https://trialsearch.who.int/Trial2.aspx?TrialID=NL7803

International Registered Report Identifier (IRRID)

DERR1-10.2196/38190

Genome-Wide Association Study of Clinical Outcome After Aneurysmal Subarachnoid Haemorrhage: Protocol

Aneurysmal subarachnoid haemorrhage (aSAH) results in persistent clinical deficits which prevent survivors from returning to normal daily functioning. Only a small fraction of the variation in clinical outcome following aSAH is explained by known clinical, demographic and imaging variables; meaning additional unknown factors must play a key role in clinical outcome. There is a growing body of evidence that genetic variation is important in determining outcome following aSAH. Understanding genetic determinants of outcome will help to improve prognostic modelling, stratify patients in clinical trials and target novel strategies to treat this devastating disease. This protocol details a two-stage genome-wide association study to identify susceptibility loci for clinical outcome after aSAH using individual patient-level data from multiple international cohorts. Clinical outcome will be assessed using the modified Rankin Scale or Glasgow Outcome Scale at 1–24 months. The stage 1 discovery will involve meta-analysis of individual-level genotypes from different cohorts, controlling for key covariates. Based on statistical significance, supplemented by biological relevance, top single nucleotide polymorphisms will be selected for replication at stage 2. The study has national and local ethical approval. The results of this study will be rapidly communicated to clinicians, researchers and patients through open-access publication(s), presentation(s) at international conferences and via our patient and public network.

Auditory outcome following aneurysmal subarachnoid haemorrhage

Auditory deficits are increasingly recognised following aneurysmal subarachnoid haemorrhage (aSAH) and are thought to be of central rather than peripheral origin. Central hearing impairment, also known as auditory processing disorder (APD), often coexists with cognitive deficits and it is thought that APD has both auditory and cognitive elements. The aim of this study was to assess auditory outcome following aSAH and its relationship with cognition. A retrospective case-controlled study design was employed with aSAH cases and matched controls identified from the UK Biobank. Auditory and cognitive outcomes were assessed using the digit triplet test (DTT) and a test of psychomotor reaction time, respectively. Best DTT score was compared between cases and controls using the t-test. A regression-based mediation analysis was performed to assess whether cognition mediated auditory outcome. 270 aSAH patients with auditory outcomes were identified with an average follow-up of 106 months. A matched control cohort of 1080 individuals was also identified. The aSAH cohort had significantly impaired best DTT scores compared to matched controls (p = 0.002). Cognition significantly mediated auditory outcome following aSAH, accounting for 9.8% of the hearing impairment after aSAH. In conclusion significant hearing impairment follows aSAH. The deficit is bilateral and non-progressive. There is a link with cognitive deficit, pointing to a central rather than peripheral source, in keeping with an auditory processing disorder. All aSAH patients should be asked about hearing difficulty at follow-up and when present it should be investigated with peripheral and central auditory assessments, as well as cognitive tests.

Long-Term Cognitive Outcome following Aneurysmal Subarachnoid Haemorrhage

OBJECTIVES

Survivors of aneurysmal subarachnoid haemorrhage (aSAH) frequently suffer from cognitive dysfunction. The aim of this study was to assess, in a large sample size with long term follow-up, the characteristics of cognitive dysfunction following aSAH and explore whether cognitive deficits mediate employment outcome.

MATERIALS AND METHODS

In this retrospective case-controlled study, aSAH survivors (n = 884) were identified from the UK Biobank and compared to matched controls (n = 3536). Controls were propensity score matched according to age, sex, Townsend deprivation score, educational status and relevant medications known to influence cognition. Cognitive outcomes and employment status were compared between cases and controls using group comparison and cross-tabulation tests. A regression-based mediation analysis was performed to assess whether cognitive deficits mediate employment status following aSAH.

RESULTS

Psychomotor reaction time and employment status significantly differed between aSAH cases and controls with slower reaction times (p < 0.001) and more unemployment or inability to work due to illness (p < 0.001) in the aSAH cohort at a mean follow-up of 125 months. Psychomotor slowing was estimated to mediate a significant proportion (6.59%) of the effect of aSAH on employment status.

CONCLUSIONS

Psychomotor reaction time and employment status differed significantly between aSAH cases and control matched individuals in the UK Biobank. Psychomotor slowing following aSAH had a discernible impact on employment status. Psychomotor reaction time and employment status are practical to acquire and can be used as surrogate measures of outcome in future studies of aSAH survivors.

Dynamic causal modeling of the working memory system of aneurysmal subarachnoid hemorrhage patients: Searching for targets for cortical intervention

INTRODUCTION

Aneurysmal subarachnoid hemorrhage (aSAH), caused by rupture of an intracranial aneurysm and bleeding into the subarachnoid space, is a life-threatening cerebrovascular disease. Because of improvements in clinical interventions, the mortality rate of aSAH is gradually decreasing. Thus, many survivors recover from aSAH but still have sequelae. Working memory (WM) deficit is one of the most common and severe sequelae after aSAH. Interestingly, the severity of WM deficit is not identical to the extent or localization of brain damage, which implies an underlying mechanism of WM deficit other than direct hemorrhagic brain damage. Previous studies have revealed altered neural activity of several brain regions during stimulus tasks. However, the behaviors and functional organization of these corresponding areas in the resting state remain unclear. Insights into the organization of the WM network could reveal novel information about the mechanism of WM deficits, which will be of great value in developing new therapeutic strategies.

METHODS

In this study, we recruited 50 aSAH patients consisting of survivors with either impaired or intact WM (two groups). Independent component analysis was performed on resting state data to extract the WM network. Dynamic causal modeling was then performed to assess the intrinsic coupling between key regions of the WM network. A model describing the neural activity and functional organization of the WM network was established, although some connections were not consistent in the resting state.

RESULTS

We found that effective connectivity of the precuneus (PCUN)-middle temporal gyrus (MTG), MTG-PCUN, and middle frontal gyrus-inferior parietal lobule was significantly decreased in the impaired WM group, which suggests a vital and central role of affected regions or connections and provides new targets for brain stimulation.

CONCLUSIONS

The results of this study may contribute to new therapeutic or rehabilitation strategies for aSAH patients with WM deficits.

Evaluation of the utility of early routine computed tomography angiography in subarachnoid hemorrhage patient outcomes

OBJECTIVES

The role of an early CTA approach in neurologically stable patients with nontraumatic SAH has not been assessed. This study explored the use of CTA in clinically stable SAH patients to pre-emptively identify cerebral vasospasm, to evaluate whether this approach is associated with improved clinical outcomes.

METHODS

We conducted a retrospective chart review of SAH patients presenting between July 2007 and December 2016 in a single academic center. Patients were divided into two groups: (1) Early CTA (stable patients who underwent a CTA between days 5-8 post-SAH), and (2) Standard Protocol. The co-primary outcomes were a composite of the mRS at discharge and last clinical follow-up (good = 0-2; poor = 3-6). A multivariable binary logistic regression was conducted to compare both groups against outcomes, controlling for potential confounders.

RESULTS

A total of 415 patients were included, 103 (24.8%) with early CTA, and 312 (75.2%) undergoing the standard protocol; the mean age was 57 years and 248 (59.8%) patients were female. Patients in the early CTA group had a higher modified Fisher grade (3-4) (87.4% vs 63.1%; p < 0.02). The multivariable analysis showed that early CTA was independently associated with lower poor outcomes at discharge (OR = 0.21, 95% CI 0.07-0.61, p = 0.004). Plus, vasospasm detection was associated with an increased risk of poor outcomes (OR = 4.77, 95% CI 1.41 - 16.10, p = 0.01). Early CTA was not associated with outcomes at clinical follow-up.

CONCLUSION

The early CTA surveillance approach was associated with better functional outcomes at discharge when compared to the current imaging standard practice.

Transcranial Doppler for Early Prediction of Cognitive Impairment after Aneurysmal Subarachnoid Hemorrhage and the Associated Clinical Biomarkers

Methods

Prospective study included 40 cases with acute aSAH. Initial evaluation by Glasgow Coma Scale (GCS) and the severity of aSAH was detected by both the clinical Hunt and Hess and radiological Fisher's grading scales. TCD was done for all patients five times within 10 days measuring the mean flow velocities (MFVs) of cerebral arteries. At the 3-month follow-up, patients were classified into two groups according to Montreal Cognitive Assessment (MoCA) scale: the first group was 31 cases (77.5%) with intact cognitive functions and the other group was 9 cases (22.5%) with impaired cognition.

Results

Patients with impaired cognitive functions showed significantly lower mean GCS (p = 0.03), significantly higher mean Hunt and Hess scale grades (p = 0.04), significantly higher mean diabetes mellitus (DM) (p = 0.03), significantly higher mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) (p = 0.02 and p = 0.005, respectively), and significantly higher MFVs measured within the first 10 days. The patients with cognitive impairment were accompanied by a higher incidence of hydrocephalus (p = 0.01) and a higher incidence of delayed cerebral ischemia (DCI) (p < 0.001). Logistic regression analysis detected that MFV ≥ 86  cm/s in the middle cerebral artery (MCA), MFV ≥ 68  cm/s in the anterior cerebral artery (ACA), and MFV ≥ 45  cm/s in the posterior cerebral artery (PCA) were significantly associated with increased risk of cognitive impairment.

Conclusion

Cognitive impairment after the 3-month follow-up phase in aSAH patients was 22.5%. Acute hydrocephalus and DCI are highly associated with poor cognitive function in aSAH. Increased MFV is a strong predictor for poor cognitive function in aSAH. This trial is registered with NCT04329208.

A meta-analysis of executive functions among survivors of subarachnoid haemorrhage

Subarachnoid Haemorrhage (SAH) is a type of stroke which is suggested to result in Executive Functioning (EF) deficits. Within the SAH research, EF is typically assessed as a unitary cognitive construct. Therefore, the nature and extent to which the different components of EF are impacted post SAH remain unclear. In this meta-analysis, 10 studies met selection criteria including 248 SAH participants, treated by endovascular coiling. Participants were assessed by EF measures and compared with 230 controls. Searches were conducted in November 2018 including Medline, PsychINFO, Web of Science, Scopus and CINAHL databases. EF measures were assigned to categories including Cognitive Flexibility, Working Memory, Inhibitory Control and Planning/Problem Solving [Diamond, 2013. Executive functions. Annual Review of Psychology, 64(1), 135-168. https://doi.org/10.1146/annurev-psych-113011-143750]. A statistically significant effect was found for overall EF. Cognitive Flexibility (G = -0.76) and Inhibitory Control (G = -0.51) generated moderate effect sizes, while Working Memory and Planning/Problem Solving found a small effect size (G = -0.45 and G = -0.49, respectively). The I² statistic suggested small to moderate heterogeneity between studies, hypothesized to relate to different cognitive tools. Underlying components of EF appear to be differentially impacted post SAH, with Cognitive flexibility demonstrating the largest degree of deficit. Recommendations for a standardized and uniform assessment of EF post SAH are outlined.

Aneurysmal subarachnoid hemorrhage: A pilot study for using longitudinal cognitive and neuropsychological testing for functional outcomes

OBJECTIVES

Patients with aneurysmal subarachnoid hemorrhage (aSAH) often sustain substantial cognitive and functional impairment. Traditional outcome measures have emphasized radiographic and gross clinical outcomes, but cognitive and functional outcomes are less frequently documented. This pilot study assessed the feasibility of administering longitudinal cognitive and neuropsychological testing and tracked patterns of functional improvement in aSAH patients.

PATIENTS AND METHODS

Standardized cognitive and neuropsychological testing were administered to a prospective cohort of aSAH patients admitted for treatment to our tertiary care center. Thirty consecutive aSAH patients (Hunt and Hess score 1-3) were enrolled over 23-months and baseline evaluations were completed within 24-h after admission. Patients were followed prospectively after treatment (coiling or clipping) at 1-, 3-, 6-, and 12-months. Functional outcome measures included the Montreal Cognitive Assessment, the Neuropsychiatric Inventory-Questionnaire, and the Functional Activities Questionnaire.

RESULTS

Of the 30 patients, 23 (77%) followed-up at 3-months, 21 (70%) at 6-months, and 19 (63%) at 12-months. Improvement from baseline to follow-up at 12-months was noted for general cognitive function (p = .004), memory (p = .025), and executive function (p = .039), with the greatest improvement occurring within 6-months. Daily function also improved mostly within 6-months (p = .022) while changes in neuropsychological disturbances were insignificant from baseline to follow-up at 12-months (p = .216).

CONCLUSION

Standardized cognitive and neuropsychological testing provides metrics for evaluating functional outcomes following treatment of aSAH. The addition of a brief battery of tests to routine clinical and radiographic evaluations is feasible. The main limitations are related to practice and referral patterns, and future studies are needed to evaluate the impact of treatment modalities on functional outcomes.

Extracellular vesicle-mediated transfer of miR-21-5p from mesenchymal stromal cells to neurons alleviates early brain injury to improve cognitive function via the PTEN/Akt pathway after subarachnoid hemorrhage

Patients with subarachnoid hemorrhage (SAH) often suffer from cognitive function impairments even when they have received proper treatment, such as the clipping or coiling of aneurysms, and this causes problems with returning to work and burdens the family. Increasing attention has been paid to mesenchymal stem cell (MSC)-derived extracellular vesicle (MSC-EV) as promising therapeutic vesicles for stroke management. In this study, we explored the potential role of MSC-EV in a rat model of SAH. We observed that MSC-EV ameliorated early brain injury (EBI) after SAH by reducing the apoptosis of neurons and that SAH induced an increase in the expression level of miR-21 in the prefrontal cortex and hippocampus. In addition, using miRNA profiling and CSF sequencing data from the exRNA Atlas, we demonstrated that EV-derived miR-21 protected neurons from apoptosis and alleviated SAH-induced cognitive dysfunction. The neuroprotective role of MSC-EV was abrogated by miR-21 knockdown or the administration of MK2206, a PTEN/Akt inhibitor. Overall, our results suggest that MSC-EV promotes neuronal survival and alleviates EBI after SAH through transferring miR-21 to recipient neurons.

The post-aSAH syndrome: a self-reported cluster of symptoms in patients with aneurysmal subarachnoid hemorrhage

OBJECTIVE

Although many patients recover to a good functional outcome after aneurysmal subarachnoid hemorrhage (aSAH), residual symptoms are very common and may have a large impact on the patient's daily life. The particular cluster of residual symptoms after aSAH has not previously been described in detail and there is no validated questionnaire that covers the typical problems reported after aSAH. Many of the symptoms are similar to post-concussion syndrome, which often is evaluated with the Rivermead Post-Concussion Symptoms Questionnaire (RPQ). In the present study, the authors therefore performed an exploratory use of the RPQ as a template to describe post-aSAH syndrome.

METHODS

The RPQ was administered to 128 patients in the chronic phase after aSAH along with a battery of quality-of-life questionnaires. The patients also underwent a medical examination besides cognitive and physical testing. Based on their RPQ scores, patients were dichotomized into a "syndrome" group or "recovery" group.

RESULTS

A post-aSAH syndrome was seen in 33% of the patients and their symptom burden on all RPQ subscales was significantly higher than that of patients who had recovered on all RPQ subscales. The symptom cluster consisted mainly of fatigue, cognitive problems, and emotional problems. Physical problems were less frequently reported. Patients with post-aSAH syndrome scored significantly worse on mobility and pain scores, as well as on quality-of-life questionnaires. They also had significantly poorer scores on neuropsychological tests of verbal learning, verbal short- and long-term memory, psychomotor speed, and executive functions. Whereas 36% of the patients in the recovery group were able to return to their premorbid occupational status, this was true for only 1 patient in the syndrome group.

CONCLUSIONS

Approximately one-third of aSAH patients develop a post-aSAH syndrome. These patients struggle with fatigue and cognitive and emotional problems. Patients with post-aSAH syndrome report more pain and reduced quality of life compared to patients without this cluster of residual symptoms and have larger cognitive deficits. In this sample, patients with post-aSAH syndrome were almost invariably excluded from return to work. The RPQ is a simple questionnaire covering the specter of residual symptoms after aSAH. Being able to acknowledge these patients' complaints as a defined syndrome using the RPQ should help patients to accept and cope, thereby alleviating possible secondary distress produced.

Dynamics of outcome after aneurysmal subarachnoid hemorrhage

In this observational study, we analyzed and described the dynamics of the outcome after aneurysmal subarachnoid hemorrhage (SAH) in a collective of 203 cases. We detected a significant improvement of the mean aggregate modified Rankin Score (mRS) in every time interval from discharge to 6 months and up to 1 year. Every forth to fifth patient with potential of recovery (mRS 1-5) at discharge improved by 1 mRS point in the time interval from 6 month to 1 year (22.6%). Patients with mRS 3 at discharge had a remarkable late recovery rate (73.3%, p = 0.000085). Multivariate analysis revealed age ≤ 65 years (odds ratio 4.93; p = 0.0045) and "World Federation of Neurological Surgeons" (WFNS) grades I and II (odds ratio 4.77; p = 0.0077) as significant predictors of early improvement (discharge to 6 months). Absence of a shunting procedure (odds ratio 8.32; p = 0.0049) was a significant predictor of late improvement (6 months to 1 year), but not age ≤ 65 years (p = 0.54) and WFNS grades I and II (p = 0.92). Thus, late recovery (6 month to 1 year) is significant and independent from age and WFNS grade.

Microstructural White Matter Abnormalities and Cognitive Impairment After Aneurysmal Subarachnoid Hemorrhage

Background and Purpose- Aneurysmal subarachnoid hemorrhage (aSAH) may have detrimental effects on white matter microstructure, which may in turn explain the cognitive impairments that occur often after aSAH. We investigated (1) whether the white matter microstructure is altered in patients with aSAH compared with patients with an unruptured intracranial aneurysm and (2) whether these abnormalities are associated with cognitive impairment 3 months after ictus. Methods- Forty-nine patients with aSAH and 22 patients with an unruptured intracranial aneurysm underwent 3T brain magnetic resonance imaging, including a high-resolution diffusion tensor imaging sequence. Patients with aSAH were scanned 2 weeks and 6 months after ictus. Microstructural white matter alterations were quantified by the fractional anisotropy and mean diffusivity (MD). Cognition was evaluated 3 months after ictus. Results- Patients with aSAH had higher white matter MD 2 weeks after ictus than patients with an unruptured intracranial aneurysm (mean difference±SEM, 0.3±0.01×10^-3 mm2/s; P≤0.01), reflecting an abnormal microstructure. After 6 months, the MD had returned to the level of the unruptured intracranial aneurysm group. No between-group differences in fractional anisotropy were found (-0.01±0.01; P=0.16). Higher MD at 2 weeks was associated with cognitive impairment after 3 months (odds ratio per SD increase in MD, 2.6; 95% CI, 1.1-6.7). The association between MD and cognitive impairment was independent of conventional imaging markers of aSAH-related brain injury (ie, cerebral infarction, hydrocephalus, total amount of subarachnoid blood, total brain volume, or white matter hyperintensity severity). Conclusions- Patients with aSAH have temporary white matter abnormalities in the subacute phase that are associated with cognitive impairment at 3 months after ictus.

RECOVERY OF MEMORY AFTER CEREBRAL ARTERY ANEURYSM SURGERY

The principal study objective was to define whether memory deficits (numerical, working, verbal-mechanical, verbal-logical and visual memory) occurred in patients submitted to surgery for brain artery aneurysm and whether significant recovery of memory took place with time. The study sample included 92 patients, i.e. 35 (38%) male and 57 (62%) female patients aged 27 to 76 years. Neuropsychological testing was conducted at Zagreb University Hospital Centre, Department of Neurosurgery, from 1998 to 2012, in two time intervals: first within 11 months following surgery, and then 12 to 48 months after surgery. The obtained results showed that verbal-mechanical, verbal-logical, and visual memory deficits were present in the first testing interval. In the second testing, the verbal-logical and visual memory deficits were still present, while the tests of verbal-mechanical memory showed deficits in capacity and learning curve, but the results for short- and long-term memory were within the normal ranges. Neither the first nor the second testing showed deficits of numerical and working memory. Based on our results, we can conclude that long-term verbal-mechanical and visual short- and long-term memory had recovered to a statistically significant level, whereas other types of memory showed no significant recovery.

Predictors of cognitive function in the acute phase after aneurysmal subarachnoid hemorrhage

BACKGROUND

Cognitive dysfunction is the most common form of neurological impairment after aneurysmal subarachnoid hemorrhage (aSAH) in the chronic phase. Cognitive deficits in the acute phase after aSAH, however, remain scarcely investigated. The aim of the present study was to test cognitive function and to identify medical predictors of cognitive deficits in the acute phase of aSAH.

METHODS

Prospective study including 51 patients treated for aSAH. Patients were treated in accordance with a standardized institutional protocol and subjected to neuropsychological evaluation around discharge from neurosurgical care. The neuropsychological test results were transformed into a global cognitive impairment index where an index value of 0.00 is considered normal and 1.00 is considered maximally pathological. Patients with an index score of less than 0.75 were considered having good global cognitive function while those with an index score equal to or above 0.75 were considered having poor global cognitive function. Univariate and multiple regression analysis were used to identify medical predictors of cognitive function.

RESULTS

Fifty-seven percent of the patients had poor cognitive function. They showed severe cognitive deficits, with most tests falling well below two standard deviations from the expected normal mean. Poor cognitive function was not reflected in a poor modified Rankin score in almost half of the cases. Patients with good cognitive function showed only mild cognitive deficits with most tests falling only slightly below the normal mean. Delayed memory was the most affected function in both groups. Univariate analysis identified acute hydrocephalus and aSAH-acquired cerebral infarction to be predictors of poor cognitive function. Cerebrospinal fluid drainage in excess of 2000 ml six-folded the risk of poor cognitive function, whereas a new cerebral infarction 11-folded the respective risk of poor cognitive function.

CONCLUSION

More than half of aSAH patients have severe cognitive deficits in the acute phase. The modified Rankin Score should be combined with neuropsychological screening in the acute phase after aSAH to get a more accurate description of the patients' disabilities. Acute hydrocephalus and aSAH-acquired cerebral infarction are the strongest predictors of poor cognitive function in the acute phase.

Cognitive Sequelae of Unruptured and Ruptured Intracranial Aneurysms and their Treatment: Modalities for Neuropsychological Assessment

BACKGROUND

Cognitive sequelae frequently follow subarachnoid hemorrhage (SAH) and include deficits across multiple domains of executive function. This factor affects overall functional outcomes negatively, especially in younger patients. Several clinical correlates predict development and severity of cognitive dysfunction after SAH. Hypothetical mechanisms of cognitive dysfunction in the absence of radiographic lesion include cerebral hypoperfusion and blood breakdown products, resulting in perturbed interneuronal communication and network synchrony, excitotoxicity, and altered microRNA expression.

METHODS

The PubMed database was searched for articles discussing cognitive outcomes in patients with unruptured and ruptured intracranial aneurysmal disease, sequelae of treatment, and modalities for neuropsychologic testing.

RESULTS

Treatment of unruptured intracranial aneurysms, although capable of preventing SAH, comes with its own set of complications and may also affect cognitive function. Neuropsychological tests such as the Montreal Cognitive Assessment, Mini-Mental Status Examination, and others have proved useful in evaluating cognitive decline. Studies using functional neurologic imaging modalities have identified regions with altered activation patterns during various cognitive tasks. The sum of research efforts in this field has provided useful insights and an initial understanding of cognitive dysfunction after aneurysm treatment and SAH that should prove useful in guiding and rendering future investigations more fruitful.

CONCLUSIONS

Development of finer and more sensitive neuropsychological tests in evaluating the different domains of cognitive function after aneurysm treatment and SAH in general will be useful in accurately determining outcomes after ictus and comparing efficacy of different therapeutic strategies.

Visual Working Memory Encoding and Recognition in Good Outcome Aneurysmal Subarachnoid Patients

Objectives: Aneurysmal subarachnoid hemorrhage (aSAH) accounts for less than 5% of strokes but is associated with significant morbidity and mortality. Amongst survivors, neurocognitive complaints are common, often despite normal imaging. We used magnetoencephalography (MEG) to investigate neurophysiological function during a visual working memory task in aSAH survivors with good recovery and normal structural imaging.

Methods: Patients with aSAH treated with coiling and exhibiting good outcome measured by Glasgow Outcome Scale (GOS) and without related parenchymal structural lesions in post-treatment MRI, were recruited and compared to age- and sex-matched controls. All participants underwent intelligence and cognitive screening, structural MRI, and MEG testing in conjunction with a 1-back visual working memory task. Sensor-level global field power and virtual electrode source analysis of neuronal activity and connectivity in aSAH were assessed.

Results: Thirteen patients and 13 matched controls were enrolled (age: 56 ± 11 years, 19 female). The 1-back task was completed with similar accuracy despite a trend for a longer reaction time in aSAH patients (p = 0.054). During encoding and recognition phases, aSAH patients showed significantly increased neuronal activation and hyperconnectivity in periventricular areas, specifically the anterior and posterior cingulate gyri.

Conclusions: Increased posterior and anterior cingulate gyri neuronal activity is demonstrated in aSAH patients during visual working memory tasks, in the absence of structural lesions. These areas work mainly as a hub to “organize” memory storage and retrieval. Increased activity in these areas might be compensatory due to injury and consequently loss of neuronal response in connected areas in the working memory networks.

Neurocognitive outcomes after aneurysmal subarachnoid hemorrhage: Identifying inflammatory biomarkers

Aneurysmal subarachnoid hemorrhage (aSAH) is a severe type of stroke which carries a high case-fatality rate. Those who survive the ictus of aneurysm rupture harbor substantial risks of neurological morbidity, functional disability, and cognitive dysfunction. Although the pervasiveness of cognitive impairment is widely acknowledged as a long-term sequela of aSAH, the mechanisms underlying its development are poorly understood. The onset of aSAH elicits activation of the inflammatory cascade, and ongoing neuroinflammation is suspected to contribute to secondary complications, such as vasospasm and delayed cerebral ischemia. In this review, we analyze the extant literature regarding the relationship between neuroinflammation and cognitive dysfunction after aSAH. Pro-inflammatory cytokines appear to play a role in maintaining normal cognitive function in adults unaffected by aSAH. However, in the setting of aSAH, elevated cytokine levels may correlate with worse neuropsychological outcomes. This seemingly dichotomous relationship between neuroinflammation and cognition suggests that the action of cytokines varies, depending on their physiologic environment. Experimental therapies which suppress the immune response to aSAH appear to have a beneficial effect on cognitive outcomes. However, further studies are necessary to determine the utility of inflammatory mediators as biomarkers of neurocognitive outcomes, as well as their role in the management of aSAH.

Increased Frontal Lobe Activation After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND AND PURPOSE

Neurocognitive deficits are common among survivors of aneurysmal subarachnoid hemorrhage, even among those with good outcomes and no structural lesions. This study aims to probe the neurophysiological underpinnings of cognitive dysfunction among patients with ruptured intracranial aneurysms using magnetoencephalography (MEG).

METHODS

Thirteen patients who had undergone uncomplicated coiling for aneurysmal subarachnoid hemorrhage and 13 matched controls were enrolled. Neuropsychological tests were done before magnetoencephalography scans. Magnetoencephalography data were acquired in a 151-channel, whole-head magnetoencephalography system for resting state and 2 cognitive tasks (go-no-go and set-shifting). Mean time from treatment to test was 18.8 months.

RESULTS

Cognitive tasks of inhibition (go-no-go) indicated greater activation in the right anterior cingulate and inferior frontal gyrus, and cognitive set-shifting tasks (mental flexibility) indicated greater activity in the bilateral anterior cingulate cortex and right medial frontal gyrus among aneurysmal subarachnoid hemorrhage patients, with significantly different timing of activation between groups. Resting-state, beta-band connectivity of the anterior cingulate correlated negatively with Montreal Cognitive Assessment scores (left: r=-0.56; P<0.01 and right: r=-0.55; P<0.01): higher connectivity of this region was linked to poorer cognitive test performance.

CONCLUSIONS

We have shown increased activation in areas of the anterior cingulate gyrus and frontobasal regions during the execution of more demanding tasks in good grade. The degree of activation in the anterior cingulate gyrus has a negative correlation with cognitive (Montreal Cognitive Assessment) scores. These subtle differences may be related to the common neurocognitive and behavioral complaints seen in this patient population.

Detection of Neuroinflammation in a Rat Model of Subarachnoid Hemorrhage Using [18F]DPA-714 PET Imaging

Subarachnoid hemorrhage (SAH) can lead to delayed cerebral ischemia, which increases the rate of morbidity and mortality. The detection of microglial activation may serve as a biomarker for the identification of patients at risk of this deleterious consequence. We assessed this hypothesis in a rat model of SAH in which the exploration of neuroinflammation related to microglial activation was correlated with the degree of bleeding. We used the rat filament model and evaluated (at 48 hours postsurgery) the intensity of neuroinflammation using positron emission tomography (PET) imaging with the 18-kDa translocator protein (TSPO) tracer [¹⁸F]DPA-714, quantitative autoradiography with [³H]PK-11195, and SAH grade by postmortem brain picture. High SAH grades were strongly and positively correlated with in vivo PET imaging of TSPO in the cortex and striatum. In addition, a positive correlation was found in the cortex in TSPO, with densities determined by imaging and autoradiographic approaches. Qualitative immunofluorescence studies indicated that overexpression of TSPO was linked to astrocytic/microglial activation. In this model, PET imaging of TSPO using [¹⁸F]DPA-714 appeared to be a relevant index of the degree of bleeding, indicating that this imaging method could be used in human patients to improve the management of patients with SAH.

The Hijdra scale has significant prognostic value for the functional outcome of Fisher grade 3 patients with subarachnoid hemorrhage

PURPOSE

Despite its high prevalence among patients with aneurysmal subarachnoid hemorrhage (aSAH) and high risk of delayed cerebral ischemia (DCI), the Fisher grade 3 category remains a poorly studied subgroup. The aim of this cohort study has been to investigate the prognostic value of the Hijdra sum scoring system for the functional outcome in patients with Fisher grade 3 aSAH, in order to improve the risk stratification within this Fisher category.

METHODS

Initial CT scans of 72 prospectively enrolled patients with Fisher grade 3 aSAH were analyzed, and cisternal, ventricular, and total amount of blood were graded according to the Hijdra scale. Additionally, space-occupying subarachnoid blood clots were assessed. Outcome was evaluated after 6 months.

RESULTS

Within the subgroup of Fisher grade 3, aSAH patients with an unfavorable outcome showed a significantly larger cisternal Hijdra sum score (HSS: 21.1 ± 5.2) than patients with a favorable outcome (HSS: 17.6 ± 5.9; p = 0.009). However, both the amount of ventricular blood (p = 0.165) and space-occupying blood clots (p = 0.206) appeared to have no prognostic relevance. After adjusting for the patient's age, gender, tobacco use, clinical status at admission, and presence of intracerebral hemorrhage, the cisternal and total HSS remained the only independent parameters included in multivariate logistic regression models to predict functional outcome (p < 0.01).

CONCLUSION

The cisternal Hijdra score is fairly easy to perform and the present study indicates that it has an additional predictive value for the functional outcome within the Fisher 3 category. We suggest that the Hijdra scale is a practically useful prognostic instrument for the risk evaluation after aSAH and should be applied more often in the clinical setting.

Neopterin plasma concentrations in patients with aneurysmal subarachnoid hemorrhage: correlation with infection and long-term outcome

OBJECT Aneurysmal subarachnoid hemorrhage (aSAH) is associated with high rates of mortality and morbidity. The main predictor for the poor outcome is the World Federation of Neurosurgical Societies (WFNS) scale. However, this scale does not take into account proinflammatory events, such as infection occurring after the aSAH, which could modify the long-term status of patients. The aim of this study was to evaluate neopterin as an inflammatory biomarker for outcome and infection prediction in aSAH patients. METHODS Plasma concentrations of neopterin were measured in 61 aSAH patients (22 male and 39 female; mean age [± SD] 52.8 ± 11.8 years) using a commercial ELISA kit. Samples were collected daily for 10 days. Outcome at 12 months was determined using the Glasgow Outcome Scale (GOS) and dichotomized as poor (GOS score 1, 2, or 3) or good (GOS score 4 or 5). Infection was determined by the presence of a positive bacterial culture. RESULTS Patients with poor outcome at 12 months had higher concentrations of neopterin than patients with good outcome. In the same way, patients who had an infection during the hospitalization had significantly higher concentrations of neopterin than patients without infection (p = 0.001). Moreover, neopterin concentrations were significantly (p < 0.008) elevated in infected patients 2 days before infection detection and antibiotic therapy. CONCLUSIONS Neopterin is an efficient outcome predictor after aSAH. Furthermore, it is able to differentiate between infected and uninfected patients as early as 2 days before clinical signs of infection, facilitating earlier antibiotic therapy and better management.

Call for uniform neuropsychological assessment after aneurysmal subarachnoid hemorrhage: Swiss recommendations

BACKGROUND

In a high proportion of patients with favorable outcome after aneurysmal subarachnoid hemorrhage (aSAH), neuropsychological deficits, depression, anxiety, and fatigue are responsible for the inability to return to their regular premorbid life and pursue their professional careers. These problems often remain unrecognized, as no recommendations concerning a standardized comprehensive assessment have yet found entry into clinical routines.

METHODS

To establish a nationwide standard concerning a comprehensive assessment after aSAH, representatives of all neuropsychological and neurosurgical departments of those eight Swiss centers treating acute aSAH have agreed on a common protocol. In addition, a battery of questionnaires and neuropsychological tests was selected, optimally suited to the deficits found most prevalent in aSAH patients that was available in different languages and standardized.

RESULTS

We propose a baseline inpatient neuropsychological screening using the Montreal Cognitive Assessment (MoCA) between days 14 and 28 after aSAH. In an outpatient setting at 3 and 12 months after bleeding, we recommend a neuropsychological examination, testing all relevant domains including attention, speed of information processing, executive functions, verbal and visual learning/memory, language, visuo-perceptual abilities, and premorbid intelligence. In addition, a detailed assessment capturing anxiety, depression, fatigue, symptoms of frontal lobe affection, and quality of life should be performed.

CONCLUSIONS

This standardized neuropsychological assessment will lead to a more comprehensive assessment of the patient, facilitate the detection and subsequent treatment of previously unrecognized but relevant impairments, and help to determine the incidence, characteristics, modifiable risk factors, and the clinical course of these impairments after aSAH.

Role of Neurexin-1β and Neuroligin-1 in Cognitive Dysfunction After Subarachnoid Hemorrhage in Rats

Supplemental Digital Content is available in the text.

Neurexin-1β and neuroligin-1 play an important role in the formation, maintenance, and regulation of synaptic structures. This study is to estimate the potential role of neurexin-1β and neuroligin-1 in subarachnoid hemorrhage (SAH)-induced cognitive dysfunction.

Expression of synaptosomal-associated protein-25 in the rat brain after subarachnoid hemorrhage

Synaptosomal-associated protein-25 is an important factor for synaptic functions and cognition. In this study, subarachnoid hemorrhage models with spatial learning disorder were established through a blood injection into the chiasmatic cistern. Immunohistochemical staining and western blot analysis results showed that synaptosomal-associated protein-25 expression in the temporal lobe, hippocampus, and cerebellum significantly lower at days 1 and 3 following subarachnoid morrhage. Our findings indicate that synaptosomal-associated protein-25 expression was down-regulated in the rat brain after subarachnoid hemorrhage.

Tert-butylhydroquinone alleviates early brain injury and cognitive dysfunction after experimental subarachnoid hemorrhage: role of Keap1/Nrf2/ARE pathway

Tert-butylhydroquinone (tBHQ), an Nrf2 activator, has demonstrated neuroprotection against brain trauma and ischemic stroke in vivo. However, little work has been done with respect to its effect on early brain injury (EBI) after subarachnoid hemorrhage (SAH). At the same time, as an oral medication, it may have extensive clinical applications for the treatment of SAH-induced cognitive dysfunction. This study was undertaken to evaluate the influence of tBHQ on EBI, secondary deficits of learning and memory, and the Keap1/Nrf2/ARE pathway in a rat SAH model. SD rats were divided into four groups: (1) Control group (n=40); (2) SAH group (n=40); (3) SAH+vehicle group (n=40); and (4) SAH+tBHQ group (n=40). All SAH animals were subjected to injection of autologous blood into the prechiasmatic cistern once in 20 s. In SAH+tBHQ group, tBHQ was administered via oral gavage at a dose of 12.5 mg/kg at 2 h, 12 h, 24 h, and 36 h after SAH. In the first set of experiments, brain samples were extracted and evaluated 48 h after SAH. In the second set of experiments, changes in cognition and memory were investigated in a Morris water maze. Results shows that administration of tBHQ after SAH significantly ameliorated EBI-related problems, such as brain edema, blood-brain barrier (BBB) impairment, clinical behavior deficits, cortical apoptosis, and neurodegeneration. Learning deficits induced by SAH was markedly alleviated after tBHQ therapy. Treatment with tBHQ markedly up-regulated the expression of Keap1, Nrf2, HO-1, NQO1, and GSTα1 after SAH. In conclusion, the administration of tBHQ abated the development of EBI and cognitive dysfunction in this SAH model. Its action was probably mediated by activation of the Keap1/Nrf2/ARE pathway.

Intracranial Non-traumatic Aneurysms in Children and Adolescents

An intracranial aneurysm in a child or adolescent is a rare, but potentially devastating condition. As little as approximately 1200 cases are reported between 1939 and 2011, with many of the reports presenting diverting results. There is consensus, though, in that pediatric aneurysms represent a pathophysiological entity different from their adult counterparts. In children, there is a male predominance. About two-thirds of pediatric intracranial aneurysms become symptomatic with hemorrhage and the rate of re-hemorrhage is higher than in adults. The rate of hemorrhage from an intracranial aneurysm peaks in girls around menarche. The most common aneurysm site in children is the internal carotid artery, in particular at its terminal ending. Aneurysms in the posterior circulation are more common in children than adults. Children more often develop giant aneurysms, and may become symptomatic from the mass effect of the aneurysm (tumorlike symptoms). The more complex nature of pediatric aneurysms poses a larger challenge to treatment alongside with higher demands to the durability of treatment. Outcome and mortality are similar in children and adults, but long-term outcome in the pediatric population is influenced by the high rate of aneurysm recurrences and de novo formation of intracranial aneurysms. This urges the need for life-long follow-up and screening protocols.

Time course of recovery following poor-grade SAH: the incidence of delayed improvement and implications for SAH outcome study design

OBJECT

Data regarding the time course of recovery after poor-grade subarachnoid hemorrhage (SAH) is lacking. Most SAH studies assess outcome at a single time point, often as early as 3 or 6 months following SAH. The authors hypothesized that recovery following poor-grade SAH is a dynamic process and that early outcomes may not always approximate long-term outcomes. To test this hypothesis, they analyzed long-term outcome data from a cohort of patients with poor-grade aneurysmal SAH to determine the incidence and predictors of early and delayed neurological improvement.

METHODS

The authors reviewed outcome data from 88 poor-grade SAH patients enrolled in a prospective SAH treatment trial (the Barrow Ruptured Aneurysm Trial). They assessed modified Rankin Scale (mRS) scores at discharge, 6 months, 12 months, and 36 months after treatment to determine the incidence and predictors of neurological improvement during each interval.

RESULTS

The mean aggregate mRS scores at 6 months (3.31 ± 2.1), 12 months (3.28 ± 2.2), and 36 months (3.17 ± 2.3) improved significantly compared with the mean score at hospital discharge (4.33 ± 1.3, p < 0.001), but they did not differ significantly among themselves. Between discharge and 6 months, 61% of patients improved on the mRS. The incidence of improvement between 6-12 months and 12-36 months was 18% and 19%, respectively. Hunt and Hess Grade IV versus V (OR 6.20, 95% CI 2.11-18.25, p < 0.001) and the absence of large (> 4 cm) (OR 2.76, 95% CI 1.02-7.55, p = 0.05) or eloquent (OR 5.17, 95% CI 1.89-14.10, p < 0.01) stroke were associated with improvement up to 6 months. Age ≤ 65 years (OR 5.56, 95% CI 1.17-26.42, p = 0.02), Hunt and Hess Grade IV versus V (OR 4.17, 95% CI 1.10-15.85, p = 0.03), and absence of a large (OR 8.97, 95% CI 2.65-30.40, p < 0.001) or eloquent (OR 4.54, 95% CI 1.46-14.08, p = 0.01) stroke were associated with improvement beyond 6 months. Improvement beyond 1 year was most strongly predicted by the absence of a large stroke (OR 7.62, 95% CI 1.55-37.30, p < 0.01).

CONCLUSIONS

A substantial minority of poor-grade SAH patients will experience delayed recovery beyond the point at which most studies assess outcome. Younger patients, those presenting in better clinical condition, and those without CT evidence of large or eloquent stroke demonstrated the highest capacity for delayed recovery.

Trajectory of functional recovery after hospital discharge for subarachnoid hemorrhage

BACKGROUND

Although there are extensive data on long-term disability after subarachnoid hemorrhage (SAH), there are few data on the trajectory of functional recovery after hospital discharge.

METHODS

From October 2009 to April 2010, we prospectively followed consecutive patients with non-traumatic SAH discharged from a university hospital. Modified Rankin Scale (mRS) scores were calculated at discharge from chart review and at 6 months by standardized telephone interview. Good functional status was defined as a mRS score of 0-2, and poor status as an mRS score of 3-6. Descriptive statistics were used to assess the trajectory of functional recovery and determine the proportion of patients whose functional status improved from poor to good.

RESULTS

Among 52 patients with non-traumatic SAH (79 % aneurysmal) who were discharged alive, most (71 %) were discharged home. Median (IQR) mRS score was 3 (2-4) at discharge and 2 (1-2) at 6 months. Some functional recovery (any improvement in mRS score) was seen in most patients (83 %; 95 % CI, 72-93 %). Of the 28 patients with poor functional status at discharge, 16 (57 %) improved to good functional status at 6 months. All patients with Hunt-Hess grade 4 or 5 hemorrhages (n = 14) had poor functional status at discharge, but half (95 % CI, 20-80 %) recovered to a good functional status at 6 months.

CONCLUSIONS

Although our sample size is small, our findings suggest that a substantial proportion of patients with SAH who are disabled at discharge go on to regain functional independence within 6 months.

Identifying patient report outcomes relevant to aneurysmal subarachnoid hemorrhage follow-up

Patients recovered from subarachnoid hemorrhage can be assessed for neuropsychological dysfunction using postal questionnaires. We assessed 214 patients using various tests of memory, mood and strategic thinking. Patients in good outcome categories (modified Rankin Scale [mRS] 0-1) nevertheless exhibited mood disorder (28%), memory deficit and executive dysfunction (20%). Return to work (49%) was most influenced by previous employment status, Rankin scale and mood.

Expression of NR2B in different brain regions and effect of NR2B antagonism on learning deficits after experimental subarachnoid hemorrhage

Approximately 50% of patients who survived after aneurysmal subarachnoid hemorrhage (SAH) have cognitive or neurobehavioral dysfunction. The mechanisms are not known. NR2B, one of the subunits of N-methyl-d-aspartate (NMDA) receptors, has been proved to be an important factor for synapse function and behavior cognition. Experiment 1 aimed to investigate the timecourse of the NR2B expression in the cortex, hippocampus, and cerebellum after SAH in rats. In experiment 2, we assessed the effect of Ro 25-6981 (a specific NR2B antagonist) on regulation of learning deficits and behavioral activity following SAH. All SAH animals were subjected to injection of autologous blood into the prechiasmatic cistern once on day 0. NR2B was assessed by Western blot analysis and immunohistochemistry. Cognitive and memory changes were investigated in the Morris water maze. As a result, the expression of NR2B was decreased remarkably in SAH groups compared with the control group and the low ebb was on days 1-3. The immunohistochemical staining demonstrated expression of NR2B was present mainly in the neurons in all of the three different regions, such as the cortex, hippocampus, and cerebellum. After Ro 25-6981 intraperitoneal administration, learning deficits induced by SAH was markedly aggravated and clinical behavior scale was also significantly decreased. Our results suggest that NR2B expression is down-regulated in the brain after experimental SAH and NR2B antagonism resulted in augmentation of the development of cognitive dysfunction after SAH.

Verbal memory capacity after treatment for ruptured intracranial aneurysm--the outcomes of three psychological tests: within a month, 1 year after and 5-7 years after treatment

BACKGROUND

Verbal memory is an essential cognitive ability with scope for adequate treatment of information and for orientation in everyday life. Our study is centered on memory performance in the wake of treatment for ruptured intracranial aneurysm.

METHODS

Three psychological tests were performed: (1) within a month of the neurosurgical intervention, (2) 1 year and (3) 5-7 years after the ruptured aneurysm treatment. Under comparison are the overall results of tests for verbal memory capacity in a cohort of patients (N = 59) and in the control group.

RESULTS

Three post-treatment measurements revealed a persistent deficit of verbal memory. The cohort's average performance improved from -1.3 SD (standard deviation) below the average of the norm to -0.5 SD below the norm at the second test 1 year after treatment, while at the third test the deficit had worsened to -0.68 SD. Similarly, testing for long-term recovery at 5-7 years postoperatively showed the patients' performances to be 2/3 SD below the average of the general population.

CONCLUSIONS

The results of the study imply the need for long-term rehabilitation of memory in this particular group of patients.