Incidence Of Subarachnoid Hemorrhage Research Articles

Genetics of Intracranial Aneurysms.

Intracranial aneurysms (IAs) are localized dilatations of intracranial arteries that are because of weaknesses of the endothelial layer. These dilations vary in size (small aneurysms, 25 mm) and are classified according to their shapes: either localized sac-like pouches or long dilatations that increase the vessels diameter; these shapes are referred to, respectively, as saccular or berry aneurysms and fusiform aneurysms. Most IAs are saccular and typically occur at the arterial branching sites of the circle of Willis. Common sites of saccular IAs include the anterior communicating artery, the posterior communicating artery, internal carotid artery, the middle cerebral artery, and the basilar artery bifurcation. Although the exact pathogenesis of IA remains to be established, several hypotheses have highlighted the contribution of maladaptive vascular remodeling triggered by hemodynamic stress and inflammatory response1—a chain of events that would ultimately damage blood vessel walls and lead to IA. The worldwide prevalence of IA is estimated to be ≈3.2%.2 Subarachnoid hemorrhage (SAH) accounts for ≈5% of all strokes, and 85% of SAHs are because of aneurysmal ruptures. SAH has an incidence rate of 9 per 10 000 persons per year and a fatality rate ≈50%.3 The incidence of SAH is markedly higher in the Finnish and Japanese populations, but surprisingly, this is not because of the prevalence of IA in these populations.2 The most common clinical symptoms of aneurysmal SAH are a sudden onset of severe headache with stiff neck, vomiting, and photophobia. Unruptured IAs are usually asymptomatic and are identified through the screening of high-risk individuals or as incidental findings of magnetic resonance imaging, particularly magnetic resonance angiogram, or computerized tomographic studies. The diagnosis of IA is made by magnetic resonance angiogram, computerized tomographic angiography, or classical angiography. The diagnosis of …

Incidence and outcome of subarachnoid haemorrhage in the general and emergency department populations in Queensland from 2010 to 2014.

To determine: (i) incidence and outcome of subarachnoid haemorrhage (SAH) in the general population; and (ii) proportions of SAH in both the general ED population and in ED patients presenting with headache. A population-based study in Queensland from January 2010 to December 2014 was conducted. Data were sourced from the Australian Bureau of Statistics, Queensland Hospital Admitted Patient Data Collection linked to the Queensland death registry and ED Information System. Admitted patients with SAH were identified from ICD-10-AM codes. Inter-hospital transfers and repeat admissions for previously diagnosed SAH were excluded. Pre-hospital deaths from SAH were included. ED patients with headache were identified from ICD-10-AM codes and finding 'headache' in the triage free-text entry. The incidence of SAH, in-hospital mortality, proportions of SAH in the general ED population and ED patients with headache were calculated. There were 1975 incident cases of SAH in admitted patients and 294 pre-hospital deaths from SAH. The incidence of SAH was 9.9 (95% confidence interval [CI] 9.5-10.4) per 100 000 person-years. The incidence standardised to the 'World Standard Population' was 7.0 per 100 000 person-years. The in-hospital mortality was 23.8% (95% CI 22.0-25.8%). SAH was found in 1407 (1.9%, 95% CI 1.8-2.0) of ED patients with headache. Overall, there were 2.4 (95% CI 2.3-2.5) SAH per 10 000 of all ED attendances. The incidence of SAH was similar to that previously reported for Australia. One in 50 ED patients with headache had SAH. Ten in 50 000 ED attendances had a SAH. These estimates can assist in the risk assessment for SAH.

Size of Ruptured Intracranial Aneurysms Is Decreasing: Twenty-Year Long Consecutive Series of Hospitalized Patients.

Decrease in the incidence of subarachnoid hemorrhage over the past decades has been related to decreased smoking rates, especially among <50-year-old people. We studied whether these epidemiological changes are reflected in changes in the size and location of ruptured intracranial aneurysms (RIAs). We identified consecutive patients admitted to a nonprofit academic hospital with saccular RIAs between 1989 and 2008. We averaged and analyzed mean sizes of RIAs in 4-year admission groups. In statistical analysis, we used the χ2 test for categorical variables and the Kruskal-Wallis test to assess differences between continuous and categorical variables. For linear trend assessments, we used the linear-by-linear association and ANOVA tests. Of 2660 consecutive patients (59% women) with RIAs, 1176 (44%) were <50 years on admission. In people <50 years, the averaged annual mean size of RIAs decreased 16% from 9.2 mm in 1989 to 1992 to 7.7 mm in 2005 to 2008 in women and 13% (from 9.3 to 8.1 mm) in men (decreasing linear trend; P=0.001). RIA sizes did not change in 50-year-old or older patients, whereas the proportion of posterior circulation RIAs almost tripled to 13%, also with a linear relationship (P<0.001). The size of RIAs seems to be decreasing among younger generations of hospital-admitted subarachnoid hemorrhage patients, whereas 50-year-old and older subarachnoid hemorrhage patients have an increasing proportion of posterior circulation RIAs. These epidemiological changes are noteworthy, especially if they are universal and ongoing.

Abstract WMP26: Association of Aortic Aneurysm and Dissection With Subarachnoid Hemorrhage

Introduction: It is uncertain whether aortic diseases such as aneurysm and dissection are associated with aneurysmal subarachnoid hemorrhage (SAH). Methods: We performed a retrospective cohort study using 2008-2015 data from a nationally representative 5% sample of Medicare beneficiaries. Our exposure of interest was hospital discharge diagnosis of an unruptured or ruptured aortic aneurysm or aortic dissection. Our primary outcome was nontraumatic SAH. Predictors and the outcome were ascertained by validated International Classification of Diseases, 9 th Revision, Clinical Modification ( ICD-9-CM ) diagnosis codes . Survival statistics were used to calculate incidence rates. Cox proportional hazards analysis was used to examine the association between aortic aneurysm/dissection and SAH while adjusting for demographics, vascular risk factors, and Charlson comorbidities. Results: Among 1,781,917 beneficiaries, 32,551 (1.8%) had a documented aortic aneurysm or dissection. During 4.6 (±2.2) years of follow-up, 2,538 patients (0.14%) developed a nontraumatic SAH. The incidence of SAH was 0.09% (95% confidence interval [CI], 0.07-0.11%) per year in patients with aortic aneurysm/dissection as compared to 0.03% (95% CI, 0.03-0.03%) per year in patients without aortic aneurysm/dissection. After adjustment for demographics, stroke risk factors, and Charlson comorbidities, patients with aortic aneurysm/dissection faced an increased risk of SAH (hazard ratio, 1.9; 95% CI, 1.4-2.7). Conclusion: In a nationally representative sample of Medicare beneficiaries, aortic aneurysm/dissection was associated with an increased risk of nontraumatic SAH. This association may reflect shared vascular risk factors and/or a common genetic basis or underlying structural deficits within the arterial wall resulting in aneurysm formation.

Abstract 137: Temporal Trends in U.S. Hospitalization Rates for Subarachnoid Hemorrhage From 1994-2013

Background: It is hypothesized that the incidence of subarachnoid hemorrhage (SAH) is decreasing due to a reduction in risk factors and more aggressive treatment of unruptured cerebral aneurysms, but long-term data from broadly representative populations are lacking. Methods: We assessed temporal trends in rates of hospitalization for SAH by using the 1994 to 2013 releases of the National Inpatient Sample (NIS), which provides data on a 20% nationally representative sample of U.S. hospitalizations. We used previously validated International Classification of Diseases, 9 th Revision, Clinical Modification codes to identify hospitalizations for nontraumatic SAH. As a comparison, we also identified ICH hospitalizations since ICH shares many risk factors with SAH but is not generally amenable to preventive intervention such as aneurysm coiling or clipping. Population estimates from the U.S. census were used to calculate annual hospitalization rates per 10,000 persons. Rates were age-standardized to the 1994 U.S. general population, and linear least-square error trendlines were generated to facilitate comparisons between trends. Survey weights provided by the NIS were used to calculate nationally representative estimates. Results: During the study period, 1,862,545 patients were hospitalized with SAH and 2,292,292 patients were hospitalized with ICH. From 1994 through 2013, the age-standardized hospitalization rate for SAH declined from 5.6 (95% confidence interval [CI], 5.1-6.1) to 3.3 (95% CI, 3.1-3.6) hospitalizations per 10,000 U.S. residents. The age-standardized hospitalization rate for ICH also declined, from 6.4 (95% CI, 6.0-6.7) to 5.1 (95% CI, 4.9-5.4) hospitalizations per 10,000 individuals. Temporal trends were similar for SAH and ICH (Figure). Conclusions: We found that hospitalization rates for both SAH steadily declined in the U.S. over the past 2 decades. This was mirrored by a similar decrease in ICH hospitalizations.

Abstract TP171: Liver Cirrhosis is Associated With an Increased Risk of Aneurysmal Subarachnoid Hemorrhage

Introduction: Cirrhosis has been associated with non-traumatic subarachnoid hemorrhage (SAH). Additionally, cirrhosis appears to contribute to the development of pulmonary vascular abnormalities. We therefore sought to investigate whether cirrhosis is associated specifically with aneurysmal SAH. Methods: We performed a retrospective cohort study using 2009-2015 inpatient and outpatient claims data from a 5% sample of Medicare beneficiaries ≥66 years of age. Our exposure was cirrhosis as defined by a previously validated algorithm using inpatient and outpatient ICD-9- CM diagnosis codes. The outcome of aneurysmal SAH was identified using a validated approach requiring an inpatient ICD-9-CM diagnosis code for non-traumatic subarachnoid hemorrhage, without concomitant diagnosis codes for trauma or rehabilitation. Additionally, to further ensure we were identifying aneurysmal SAH, we required the presence of an ICD-9-CM procedure code reflecting endovascular or surgical treatment of a cerebral aneurysm during the same hospitalization. Patients were censored at the time of death or end of Medicare coverage or on September 30, 2015. We used survival statistics to calculate incidence rates and Cox proportional hazards models to evaluate the association between cirrhosis and aneurysmal SAH after adjustment for demographics, established SAH risk factors, and Charlson comorbidities. Results: We identified 10,658 (0.6%) patients with cirrhosis from among the 1,778,604 beneficiaries in our sample. The mean age of patients with cirrhosis was 73.2 (±6.5) years, and 48% were female. Over a mean of 4.7 (±2.1) years of follow-up, 4,272 patients were hospitalized with aneurysmal SAH. The annual incidence of aneurysmal SAH in patients with cirrhosis was 0.11% (95% confidence interval [CI], 0.08-0.17%) compared to 0.05% (95% CI, 0.05-0.05%) in patients without cirrhosis. After adjustment for demographics, risk factors, and comorbidities, cirrhosis was independently associated with an increased risk of aneurysmal SAH (hazard ratio, 2.3; 95% CI, 1.5-3.4). Conclusions: We found that cirrhosis was associated with aneurysmal SAH among Medicare beneficiaries. Liver cirrhosis may be an independent risk factor for aneurysmal SAH.

Abstract TP86: Post Hoc Subgroup Analysis of Unruptured Cerebral Aneurysm in Japan Special Reference to Small Sized Aneurysm

Introduction: In Japan, asymptomatic unruptured cerebral aneurysms (UCA) are frequently discovered at brain check-ups. The overall annual rupture rate of these aneurysms has been reported as 0.95% according to UCAS Japan. Japanese people have a 2.8-times increased risk of rupture in UCA according to PHASES score. According to the recent reports, the rate of the small sized ruptured cerebral aneurysm ≤ 5mm (RCA) was over 35%. In this paper, we discuss the post hoc subgroup analysis of UCA in Japan special reference to small aneurysms. Subjects and Methods: From January 2001 to March 2004, a total of 6697 UCAs among 5720 patients were prospectively registered from any one of 283 institutions in Japan. In a subgroup of small UCAs ≤ 4mm (sUCA), aneurysms which developed a subarachnoid hemorrhage were extracted for this post hoc analysis. Intrapatient comparisons of each sUCAs were carried out using aneurysm specific factors such as size, location, calcification, thrombosis and shape, and patient specific factors such as age, sex, the reason of discovery for UCA, hypertension, hyperlipidemia, smoking, polycystic kidney and old cerebral infarction. Multivariate logistic regression analysis for rupture by JMP software was performed. Results: Eight sUCAs among 3132 sUCAs were ruptured and the annual rupture rate was 0.35% / year. By multivariate logistic regression analysis for rupture, the sCUA discovered by brain check-ups (OR: 3.69, CI: 1.02 – 15.5) and non-hyperlipidemia (OR: 5.65, CI: 1.11 – 103.9) were significant risk factors. The annual rupture rate of sUCA discovered by brain check-ups and with non-hyperlipidemia were 0.62 % and 0.42 %, respectively. Conclusions: SUCA has not indicated the category for radical treatment of UCA, however, the countermeasure for sUCA should be required to reduce the incidence of subarachnoid hemorrhage. Using of statin and any psychogenic stress might be related to rupture of sUCAs. Further precise research should be needed about the treatment for sUCA.

Elderly population have a decreased aneurysmal subarachnoid hemorrhage incidence rate than Middle aged population: a descriptive analysis of 8,144 cases in mainland China

Purpose: Rupture of an intracranial aneurysm is a life-threatening acute cerebrovascular event. The purpose of this study was to investigate whether aneurysmal subarachnoid haemorrhage (SAH) incidence rate is higher or lower in elderly population than in middle aged population.Materials and methods: Aneurysmal SAH cases were collected retrospectively from the archives of 21 hospitals in Mainland China. All the cases were collected from September 2016 and backward consecutively for a period of time up to 8 years. SAH was initially diagnosed by brain computed tomography (CT). CT angiography (CTA) or digital subtraction angiography (DSA) was followed and SAH was confirmed to be due to cerebral aneurysm rupture. For cases when multiple bleeding occurred, the age of the first SAH was used in this study. The total incidence from all hospitals at each age group were summed together for females and males respectively; then adjusted by the total population number at each age group for females and males which was from the 2010 population census of the People’s Republic of China.Results: In total there were 8,144 cases of intracranial aneurysmal SAH, with 4,861 females and 3,283 males. For females the relative aneurysmal SAH incidence rate started to decrease after around 65 years old, while for males the relative aneurysmal SAH incidence rate started to decrease after around 53 years old.Conclusion: Our data tentatively suggest elderly patients may be at a reduced risk of rupture compared with patients who are younger while have similar other risk factors.

Aneurysm Clipping and Outcome for Hunt &amp;amp; Hess Grade 4, 5 Subarachnoid Hemorrhage—A Literature Review

“Subarachnoid Hemorrhage is non-traumatic nasty bleeding into the subarachnoid area, the territory between the arachnoid and the piamater of the central nervous system showing prompt developing signs of neurological sequelae”. It is one among the neurological emergencies which is a very distressing cerebrovascular disease with complicated mechanisms that risks brain perfusion and its function, having higher morbidity and mortality rates. Its mortality rate is still ranged between 8.3% and 66.7%, with noticeable regional variations, beside recent advances in treatment approaches. The incidence of SAH among the population of 2 - 22.5/100,000 was reported with a minimum of 60% of aneurysm ruptures occurring amid ages of 40 and 60 years with 3:2 male:female ratio. The rupture risks for unruptured aneurysms are increased by the issues like present smokers, larger size of aneurysm, and amid young population. The surgical treatment decision should be contemplated upon factors such as aneurysm’s size, aneurysm’s location, patient’s illness history, and surgeon’s operative experiences. Latest technical progresses in imaging techniques, increased consideration of illness history, more awareness of incidences of aneurysms and use of micro neurosurgery, have raised the chance for detection of subarachnoid hemorrhage (SAH) and possible better outcomes with surgical management. Factors that may affect outcome include age, size and site of aneurysm, interval between ictus and surgery, CT Fisher Grade & Hunt and Hess Grading earlier to surgery, & Glasgow Coma Scale at the while of discharge. The studies here support the wide spread concept that surgical clipping of SAH for Hunt and Hess Grade 4, 5 SAH, which is also considered as poor Grade SAH stipulates an effective treatment if done earlier provides better outcome.

Subarachnoid hemorrhage after surgical treatment of unruptured intracranial aneurysms.

OBJECTIVE Only a few previous studies have investigated subarachnoid hemorrhage (SAH) after surgical treatment in patients with unruptured intracranial aneurysms (UIAs). Given the improvement in long-term outcomes of embolization, more extensive data are needed concerning the true rupture rates after microsurgery in order to provide reliable information for treatment decisions. The purpose of this study was to investigate the incidence of and risk factors for postoperative SAH in patients with surgically treated UIAs. METHODS Data from 702 consecutive patients harboring 852 surgically treated UIAs were evaluated. Surgical treatments included neck clipping (complete or incomplete), coating/wrapping, trapping, proximal occlusion, and bypass surgery. Clippable UIAs were defined as UIAs treated by complete neck clipping. The annual incidence of postoperative SAH and risk factors for SAH were studied using Kaplan-Meier survival analysis and Cox proportional hazards regression models. RESULTS The patients' median age was 64 years (interquartile range [IQR] 56-71 years). Of 852 UIAs, 767 were clippable and 85 were not. The mean duration of follow-up was 731 days (SD 380 days). During 1708 aneurysm years, there were 4 episodes of SAH, giving an overall average annual incidence rate of 0.23% (95% CI 0.12%-0.59%) and an average annual incidence rate of 0.065% (95% CI 0.0017%-0.37%) for clippable UIAs (1 episode of SAH, 1552 aneurysm-years). Basilar artery location (adjusted hazard ratio [HR] 23, 95% CI 2.0-255, p = 0.0012) and unclippable UIA status (adjusted HR 15, 95% CI 1.1-215, p = 0.046) were significantly related to postoperative SAH. An excellent outcome (modified Rankin Scale score of 0 or 1) was achieved in 816 (95.7%) of 852 cases overall and in 748 (98%) of 767 clippable UIAs at 12 months. CONCLUSIONS In this large case series, microsurgical treatment of UIAs was found to be safe and effective. Aneurysm location and unclippable morphologies were related to postoperative SAH in patients with surgically treated UIAs.

Monthly variations in aneurysmal subarachnoid hemorrhage incidence and mortality: Correlation with weather and pollution.

Background and purposeAlthough the effect of weather and air pollution on the occurrence of subarachnoid hemorrhage (SAH) has been investigated, results have remained inconsistent. The present study aimed to determine the seasonality of aneurysmal subarachnoid hemorrhage occurrence and mortality.MethodsWe used the National Inpatient Sample database to evaluate the effect of meteorological factors and air pollutants on patients with subarachnoid hemorrhage in Korea between 2011 and 2014. Monthly variations in SAH occurrence and mortality were analyzed using locally weighted scatter plot smoothing curves. Multivariate Poisson generalized linear regression models were used to evaluate potential independent meteorological and pollutant variables associated with SAH occurrence and mortality.ResultsIn total, 21,407 patients who underwent clip or coil treatment owing to aneurysmal SAH in Korea from January 1, 2011, to December 31, 2014, were included. The crude incidence rate of SAH in Korea was 10.5 per 100,000 people per year. An approximately 0.5% lower risk of SAH was observed per 1°C increase in mean monthly temperature (relative risk, 0.995; 95% confidence interval [CI], 0.992–0.997; p < 0.001), while an approximately 2.3% higher risk of SAH was observed per 1°C increase in mean monthly diurnal temperature.ConclusionsWe showed distinct patterns of seasonal and monthly variation in the occurrence and mortality of SAH. Our findings suggest that meteorological factors may play an important role in monthly variations in the occurrence of aneurysmal SAH.

Anatomical variation of circle of Willis is common in patients with intracranial aneurysm: Initial registry data from tertiary health center, Surabaya, Indonesia

Background: The incidence of subarachnoid hemorrhage (SAH) in Indonesia continues to rise. Rupture of intracranial aneurysm is known to be the most common cause SAH. Intracranial aneurysm formation is associated with anatomical variation of Circle of Willis.

The five preferences for post-traumatic SAH

Acute traumatic brain injury is a worldwide public health crisis. Post-traumatic subarachnoid hemorrhage (SAH) is a finding that is present at a frequency of 40% according to data from American TCDB (1,2). Among the mechanisms that have been implicated as causes of post-traumatic SAH is the cortical bleeding through the subarachnoid space. It is estimated that the incidence of post-traumatic SAH is 11% to 60% in patients with traumatic brain injury. The brain CT is considered a technique with good sensitivity, economical and available in many hospitals worldwide. We have reviewed the literature and found some imaging characteristics of post-traumatic subarachnoid hemorrhage. We have called “the five preferences for post-traumatic SAH”.

2 Effectiveness of Provider-Focused Interventions to Eliminate Care Disparities: Results from the Equity in Diagnostic Imaging Trial (EDIT)

African Americans have almost twice the incidence of subarachnoid hemorrhage (SAH) compared to Whites, yet studies indicate they are less likely to receive neuroimaging when presenting to the emergency department (ED) with headache, even when adjusting for age, sex, co-morbidity and acuity. Regulatory efforts and quality initiatives to reduce CT imaging for ED patients with headache may exacerbate this disparity and increase the likelihood that Black patients, who are at higher risk for SAH, do not receive an appropriate ED workup for severe headache. The Equity in Diagnostic Imaging Trial (EDIT) was designed to develop and test the effect of two provider-focused interventions on this racial disparity in diagnostic imaging rates for ED patients with headache. The EDIT team designed two evidence-based, provider-focused interventions: 1) an audit-feedback (AU-FB) intervention that provided periodic information on the higher incidence of SAH among Blacks and their lower rates of neuroimaging; and 2) clinical decision support (CDS) embedded in the electronic health record with similar content. These interventions were tested in sequential blinded, randomized, controlled trials; providers were unaware of the study. Attending physicians, emergency medicine residents, and physician assistants working in the adult ED of a large urban academic medical center were randomized to either AU-FB or control. After a 12-month intervention period and a 9-month washout period, providers were re-randomized to either CDS or control for another 12-month period. All adult patient visits (age ≥ 18), identified through an automated report of patients for whom an adult headache template was used by the ED clinician during the study period, were reviewed. Patients with history of trauma were excluded. Data elements, abstracted by automated reports and structured manual review by trained research staff, included: ED provider names; patient age, sex, race, ethnicity, insurance type, emergency severity index, chief complaint, vital signs, pain score, neuro imaging order, ED disposition, ED diagnosis, and elements of the prior medical history, history of present illness, and physical examination significantly associated with the decision to order diagnostic imaging in a previously reported observational study, which confirmed the presence of a Black-White imaging disparity at the study site. Comorbidities were categorized using the Elixhauser Comorbidity Index. 8,185 ED visits were reviewed; 130 (1.6%) of these were ED revisits within 2 days of a previous ED visit for headache. These were dropped resulting in a final sample of 8,055 visits. The primary outcome for both trials is likelihood of a neuroimaging order for Black vs White patients. Secondary analyses will examine neuroimaging for all racial/ethnic/sex patient groups; comparative effectiveness of the two interventions; provider subgroups (attending, resident, PA); and concordance vs discordance of provider-patient race/ethnicity. The EDIT Trial tested the effectiveness of two provider-focused interventions addressing a racial disparity in diagnostic imaging rates for ED patients with headache. These interventions are particularly timely given current efforts to decrease CT utilization for ED patients with headache.

Regional differences in the incidence of aneurysmal subarachnoid haemorrhage in Finland.

Over the years, the consensus has generally been that Finland is a country with a significantly high incidence of aneurysmal subarachnoid haemorrhage (SAH) when compared to the rest of the world, excluding Japan. Most of the traditionally cited Finnish incidence studies are several decades old and have clear differences in their methodology and study design. The objective of this study was to determine the hospital-admitted incidence of aneurysmal SAH at Tampere University Hospital between 1990 and 2014. We also compared the incidence to other geographical regions in Finland. The material for this study consists of patients admitted to Tampere University Hospital between 1990 and 2014 with the presentation of aneurysmal SAH. There was a total of 1965 patients with aneurysmal SAH in our data. The mean hospital-admitted aneurysmal SAH incidence over the period was 7.41 per 100,000 person-years. The hospital-admitted aneurysmal SAH incidence in the Eastern Finland region was two-thirds greater than in the Tampere University Hospital region. We observed a relatively steady hospital-admitted incidence of aneurysmal SAH (7.41 per 100,000 person-years) in the Tampere University Hospital region. This result is parallel to a recent study looking into the incidence of aneurysmal SAH for the whole of Finland. Compared to the Tampere University Hospital region, the incidence was 64% greater in the Eastern Finland region.

P.049 Seasonal variations in aneurysmal subarachnoid hemorrhage: revisiting the myth using google trends

Background: Results of previous studies examining seasonal variation in the incidence of aneurysmal subarachnoid hemorrhage (SAH) are conflicting. The aim of this study is to investigate whether there is a seasonal effect in online search queries for SAH that may reflect an association between meteorological factors and aneurysm rupture. Methods: We utilized the Google Trends data service to analyze the volume of internet queries for SAH on Google’s search engine from January 1, 2004 to November 2016. We used comprehensive search terms and collected data from: USA, Canada, Finland, and Japan, as well as worldwide search volume. Potential seasonal variations in the data were assessed by comparative non-parametric tests and curve-fit regression model. Results: Our analyses revealed that USA had the highest median search scores (115 vs. 86, 46, 46 for Finland, Canada and Japan, respectively). The term “brain aneurysm” was the commonly used search term among countries, followed by “cerebral aneurysm”. There was no evidence of seasonality in any of the countries studied on both univariate tests and regression time-adjusted analysis. Conclusions: There are no seasonal variations in internet search query volume for SAH. Further studies are needed to explore whether online search volumes correlate with the actual incidence of SAH.

Anti-embolic effect of Taorenchengqi Tang in rats with embolic stroke induced by occluding middle cerebral artery

ObjectiveTo investigate the anti-embolic effect of Taorenchengqi Tang (TRCQT), a formulas from Traditional Chinese Medicine, plus aspirin in rats with embolic stroke induced by selective occlusion of the middle cerebral artery (MCA). Possible side effects of hemorrhagic incident and other bleeding events and anti-platelet effect were also explored. MethodsNinety rats were randomly separated into 9 groups (n = 10): group 1 a sham-operated group (n = 10); groups 2 and 3 orally treated with an isovolumetric solvent (distilled water) for 1 and 3 months, followed by thromboembolic occlusion (n = 10); groups 4 and 5 orally treated with aspirin (5 mg/kg) alone for 1 and 3 months, followed by thromboembolic occlusion (n = 10); groups 6 and 7 orally treated with TRCQT (0.5 g/kg) alone for 1 and 3 months, followed by thromboembolic occlusion (n = 10); groups 8 and 9 orally treated with TRCQT plus aspirin for 1 and 3 months, respectively followed by thromboembolic occlusion (n = 10). The ischemic stroke in rats was induced by selective MCA occlusion. One was orally administered. After the treatments, rats' brains were removed, sectioned and stained with triphenyltetrazolium chloride (TTC) for infarct volume measurement. The incidence of subarachnoid hemorrhage (SAH) and intracerebral hemorrhage (ICH) were observed. A potential gastric bleeding side effect was assessed by measuring hemoglobin (Hb), and prothrombin time (PT). Collagen-induced platelet activation and tail vein bleeding time were measured. ResultsTreatment with TRCQT alone or in combination with aspirin reduced infarct volume for 1 (P < 0.05), and 3 (P < 0.01) months without SAH and ICH incidences, and gastric bleeding. TRCQT treatment for 1 month was also not altered PT. Moreover, a concentration dependent inhibition of collagen-induced platelet activation, followed by increasing of tail vein bleeding time was observed after TRCQT treatment. ConclusionEither TRCQT alone or TRCQT plus aspirin exhibits potent neuroprotective effect by reducing infarct volume without changing the status of SAH, ICH and gastric bleeding possibly via inhibiting the platelet activation and increasing bleeding time.

Subarachnoid Hemorrhage in Germany Between 2010 and 2013: Estimated Incidence Rates Based on a Nationwide Hospital Discharge Registry.

Nordic countries are the primary source for nationwide data on the incidence of subarachnoid hemorrhage (SAH). Reliable estimates of national incidence rates of SAH in other countries are lacking, yet studies from Nordic countries with exceptional incidence rates are sometimes disregarded because of concerns regarding external validity. Autopsies are rarely performed for sudden deaths; therefore, estimates of the SAH incidence commonly reflect the hospital discharge rates. Our aim was to estimate the nationwide incidence of nontraumatic SAH in Germany using a national hospital discharge register. The German federal statistical office provided the number of patients discharged from all German hospitals between 2010 and 2013 with the primary diagnosis of nontraumatic SAH (ICD code I60.0-I60.9) and corresponding age distribution. Age-standardized attack rates of nontraumatic SAH were calculated using the 2011 German demographic distribution. Between 2010 and 2013, the overall age-standardized incidence rate of nontraumatic SAH was 11.3 per 100,000 person-years, and it reached a maximum of 22.1 per 100,000 person-years in the oldest age group. The absolute number of SAHs was highest in the 50-55-year age group. The distribution of intracranial aneurysms displayed a propensity toward the posterior circulation with advancing age (P < 0.001), although in absolute numbers SAH originated mostly from the anterior circulation. Our estimate of the German nationwide attack rate suggests that the incidence of nontraumatic SAH is more homogeneous than previously assumed. Rejecting the external validity of studies from countries believed to display an exceptional incidence rates may therefore not be justified.

Complicated Mild Traumatic Brain Injury and the Need for Imaging Surveillance.

To evaluate the need for repeat head computed tomography (CT) in patients with complicated mild traumatic brain injury (TBI) determined nonoperative after the first head CT. A total of 380 patients with mild TBI and a positive head CT not needing surgery were included. Changes between first and second head CT were categorized as decreased, increased, or stable. Three patients required neurosurgical intervention (0.8%) after the second CT. There were no significant differences in demographics including age, gender, alcohol consumption, anticoagulation status, time between first and second CT, Glasgow Coma Scale score at admission and discharge, and incidence of subarachnoid hemorrhage, epidural hematoma, contusion, or skull fractures between the operated and nonoperated groups. All patients in the operated group had subdural hematoma compared with 40.8% in the nonoperated group (P= 0.07). All operated patients showed symptoms of neurologic worsening after initial head CT, compared with 2.7% in the nonoperated group (P < 0.001). Moreover, patients who showed neurologic worsening were more likely to show increased intracranial bleeding on repeat head CT, whereas patients who did not show neurologic worsening were more likely to show decreased or stable intracranial bleeding (P= 0.04). Routine repeat head CT in patients with complicated mild TBI is very low yield to predict need for delayed surgical intervention. Instead, serial neurologic examination and observation over the first 8 hours after the injury is recommended. A second CT scan should be obtained only in patients who have neurologic worsening.

Internet search volumes in brain aneurysms and subarachnoid hemorrhage: Is there evidence of seasonality?

ObjectiveResults of previous studies examining seasonal variation in the incidence of aneurysmal subarachnoid hemorrhage (SAH) are conflicting. The aim of this brief report is to investigate whether there is a seasonal effect in online search queries for SAH that may reflect an association between meteorological factors and aneurysm rupture. Patients and methodsWe used the Google Trends data service to analyze the volume of internet queries for SAH on Google’s search engine from January 1, 2004 to November 2016. We used comprehensive search terms and collected data from: USA, Canada, and countries known for their high prevalence of SAH (Finland, and Japan), as well as worldwide search volume. Potential seasonal variations in the data were assessed by comparative non-parametric tests and curve-fit regression model. ResultsOur analyses revealed that USA had the highest median value in cumulative search scores (115 vs. 86, 46, 46 for Finland, Canada and Japan, respectively). The term “brain aneurysm” was the commonly used search term among countries, followed by “cerebral aneurysm”. There was no evidence of seasonality in any of the countries studied on both univariate tests and regression time-adjusted analysis. ConclusionsThere are no seasonal variations in internet search query volume for SAH. Further studies are needed to explore whether online search volumes correlate with the actual incidence of SAH.