[Show abstract][Hide abstract] ABSTRACT: Stroke rates were found to have seasonal variations. However, previous studies using air temperature, humidity, or air pressure separately were not adequate, and the study catchment was not clearly drawn. Therefore, here we proposed to use a thermal index called physiologically equivalent temperature (PET) that incorporates air temperature, humidity, wind speed, cloud cover, air pressure and radiation flux from a biometeorological approach to estimate the effect of weather as physiologically equivalent on ischemic stroke onsets in an Austrian population. Eight thousand four hundred eleven stroke events in Vienna registered within the Austrian Stroke Unit Register from January 1, 2004 to December 31, 2010 were included and were correlated with the weather data, obtained from the Central Institute for Meteorology and Geodynamics in the same area and study time period and calculated as PET (°C). Statistical analysis involved Poisson regression modeling. The median age was 74 years, and men made up 49 % of the entire population. Eighty percent had hypertension while 25.4 % were current smokers. Of note, 26.5 % had diabetes mellitus, 28.9 % had pre-stroke, and 11.5 % had pre-myocardial infarction. We have observed that onsets were higher on the weekdays than on the weekend. However, we did not find any significant association between PETs and ischemic stroke onsets by subtypes in Vienna. We did not observe any significant associations between PETs and ischemic stroke onsets by subtypes in Vienna. Hospital admission peaks on the weekdays might be due to hospital administration reasons.
Environmental Science and Pollution Research 04/2015; 22(11). DOI:10.1007/s11356-015-4494-7 · 2.76 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The introduction of new direct oral anticoagulants has changed the treatment of nonvalvular atrial fibrillation. However, these changes are not yet fully reflected in current guidelines.This consensus statement, endorsed by six Austrian medical societies, provides guidance to current prophylacticapproaches of thromboembolic events in nonvalvular atrial fibrillation on the basis of current evidence and published guidelines.Furthermore, some special subjects are treated, like changes in laboratory parameters and their interpretation under treatment with direct oral anticoagulants, treatment of bleedings, approach to operations, cardioversion and ablation, and specific neurological aspects. For a CHA2DS2-VASc-Score of ≥ 2, anticoagulation is recommended with a high level of evidence (1A). At the end of the consensus statement, recommendations for a number of specific patient subgroups can be found, in order to help treating physicians to arrive at appropriate therapeutic decisions.
[Show abstract][Hide abstract] ABSTRACT: Sex-related differences in quality of acute stroke care are an important concern with limited data available, specifically regarding stroke unit (SU) setting. We used the prospective nationwide Austrian SU registry to address this issue.
Our analysis covered an 8-year time period (January 2005 to December 2012) during which all patients with transient ischemic attack or ischemic stroke admitted to 1 of 35 Austrian SU had been captured in the registry. These data were analyzed for age-adjusted preclinical and clinical characteristics and quality of acute stroke care in men and women. In addition, we assessed the outcome at 3 months in multivariate analysis.
A total of 47 209 individuals (47% women) had received SU care. Women were significantly older (median age: 77.9 versus 70.3 years), had higher pre-existing disability and more severe strokes. Correcting for age, no significant sex-related differences in quality of care were identified with comparable onset-to-door times, times to and rates of neuroimaging, as well as door-to-needle times and rates of intravenous thrombolysis (14.5% for both sexes). Despite equal acute stroke care and a comparable rate of neurorehabilitation, women had a worse functional outcome at 3-month follow-up (modified Rankin scale 3-5: odds ratio, 1.26; 95% confidence interval [1.17-1.36]), but a lower mortality (odds ratio, 0.70; 95% confidence interval [0.78-0.88]) after correcting for confounders.
We identified no disproportions in quality of care in the acute SU setting between men and women, but the outcome was significantly different. Further studies on the poststroke period including socioeconomic aspects are needed to clarify this finding.
[Show abstract][Hide abstract] ABSTRACT: Apart from missing the approved time window of 4.5 hours, one frequent cause for withholding recombinant tissue plasminogen activator (rt-PA) treatment in patients with ischemic stroke is presentation with mild deficit on admission. We analyzed in a large cohort of patients whether rt-PA treatment is beneficial for this group of patients.
From a total of 54 917 patients with ischemic stroke prospectively enrolled in the Austrian Stroke Unit Registry, 890 patients with mild deficit defined as ≤5 points in the National Institutes of Health Stroke Scale treated with and without rt-PA were matched for age, sex, prestroke disability, stroke severity, hypertension, diabetes mellitus, hypercholesterolemia, stroke cause, and clinical stroke syndrome. Functional outcome was assessed using the modified Rankin Scale at 3 months. For data visualization, weighted averages of outcome differences were computed for all age severity combinations and mapped to a color. For quantification of effect sizes, numbers need to treat were calculated.
rt-PA-treated patients with mild deficit had a better outcome after 3 months compared with matched cases without rt-PA treatment (odds ratio [OR], 1.49; 95% confidence interval [CI], 1.17-1.89; P<0.001). In rt-PA-treated patients with mild deficit, the numbers need to treat ranged from 8 to 14. Improvement achieved by rt-PA treatment was observed along the entire age range.
In our study, intravenous rt-PA treatment was beneficial for patients with mild deficit. Given the observational nature of these results, our data might serve as an incentive for future randomized controlled trials to provide a basis for optimal patient selection.
[Show abstract][Hide abstract] ABSTRACT: In 2008 the Austrian Task Force for Neuromyelitis Optica (NMO) started a nation-wide network for information exchange and multi-centre collaboration. Their aim was to detect all patients with NMO or NMO spectrum disorders (NMO-SD) in Austria and to analyse their disease courses and response to treatment.
(1) As of March 2008, 1957 serum samples (of 1557 patients) have been tested with an established cell based immunofluorescence aquaporin-4 antibody (AQP4-ab) assay with a high sensitivity and specificity (both >95%). All tests were performed in a single reference laboratory (Clinical Dept. of Neurology of the Innsbruck Medical University). (2) A nation-wide survey with several calls for participation (via email newsletters, articles in the official journal of the Austrian Society of Neurology, and workshops) was initiated in 2008. All collected data will be presented in a way that allows that every individual patient can be traced back in order to ensure transparency and to avoid any data distortion in future meta-analyses. The careful and detailed presentation allows the visualization and comparison of the different disease courses in real time span. Failure and response to treatment are made visible at one glance. Database closure was 31 December 2011. All co-operators were offered co-authorship.
All 71 NMO- or NMO-SD patients with AQP4-ab positivity (age range 12.3 to 79.6 years) were analysed in detail. Sex ratio (m:f = 1:7) and the proportion of patients without oligoclonal bands in cerebrospinal fluid (86.6%) were in line with previously published results. All identified patients were Caucasians.
A nationwide collaboration amongst Austrian neurologists with good network communications made it possible to establish a database of 71 AQP4-ab positive patients with NMO/NMO-SD. This database is presented in detail and provides the basis for further studies and international cooperation in order to investigate this rare disease.
PLoS ONE 11/2013; 8(11):e79649. DOI:10.1371/journal.pone.0079649 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Rapid initiation of intravenous thrombolysis improves patient's outcome in acute stroke. We analyzed inter-center variability and factors that influence the door-to-needle time with a special focus on process measurements in all Austrian stroke units.
Case level data of patients receiving intravenous thrombolysis in the Austrian Stroke Unit Registry were enriched with information of a structured questionnaire on center specific process measures of all Austrian stroke units. Influence of case and center specific variables was determined by LASSO procedure.
Center specific median door-to-needle time ranged between 30 and 78 minutes. Between April 2004 and November 2012, 6246 of 57991 patients treated in Austrian stroke units with acute ischemic stroke received intravenous thrombolysis. An onset-to-door time >120 minutes, patients with total anterior circulation stroke, recent year of admission, patient transportation with ambulance crew and emergency physician, the use of point of care tests reduced the door-to-needle time, whereas onset-to-door ≤60 minutes, unknown onset-to-door, patients with an NIHSS ≤4 or posterior circulation stroke, initial admission to a general emergency department, a distant radiology department, primary imaging modality other than plain CT and waiting for the lab results were associated with an increase in door-to-needle time. Case level and center specific factors could explain the inter center variability of door-to-needle times in 31 of 34 stroke units in Austria.
In light of our results it seems crucial that every single stroke center documents and critically reviews possibilities of optimizing practice strategies in acute stroke care.
PLoS ONE 09/2013; 8(9):e75378. DOI:10.1371/journal.pone.0075378 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Die Unterbrechung einer bestehenden Therapie mit Vitamin-K-Antagonisten (VKA) ist bei Patienten, die sich einem größeren operativen Eingriff unterziehen müssen, in den meisten Fällen notwendig. Der vorliegende Expertenkonsensus soll unter Berücksichtigung der rezenten Leitlinien und anderer Publikationen eine Entscheidungshilfe für eine individuelle Therapieplanung darstellen. Das Management der Antikoagulation während dieser Unterbrechung geschieht unter Berücksichtigung des thromboembolischen (TE) Risikos von Seiten der Grunderkrankung des Patienten und des Blutungsrisikos von Seiten des Eingriffes. Die bestehende Therapie mit VKA sollte in Abhängigkeit von der verwendeten Substanz 3–7 Tage vor der Intervention abgesetzt werden. Zur Überbrückung („Bridging“), bzw. Abdeckung der präoperativ langsam abklingenden und postoperativ nur langsam ansteigenden Wirkung der VKA werden fast ausschließlich niedermolekulare Heparine (NMH) eingesetzt, für die auch Erfahrungswerte aus Registerstudien vorliegen. Dabei sollte für Patienten mit einem hohem TE- Risiko die therapeutische und bei Patienten mit einem mittleren TE-Risiko die halbtherapeutische Dosis zur Anwendung kommen. Patienten mit niedrigem TE-Risiko erhalten kein „Bridging“. Postoperativ sollte jenen Patienten, die präoperativ eine therapeutische Dosis NMH erhalten haben, diese auch weiter erhalten. Im Falle größerer Eingriffe mit entsprechend erhöhtem Blutungsrisiko werden NMH ab dem 3. postoperativen Tag verabreicht. Bei kleineren operativen Eingriffen, die kein erhöhtes Blutungsrisiko mit sich bringen kann schon am 1. Tag nach dem Eingriff mit NMH begonnen werden. Patienten, die präoperativ nur eine halbtherapeutische Dosis erhalten haben, erhalten dieselbe Dosis im Fall größerer Operationen ab dem 3. postoperativen Tag, im Fall kleinerer Eingriffe ab dem 1. postoperativen Tag. Die Therapie mit VKA sollte spätestens am 2. postoperativen Tag wieder begonnen werden. Eine allenfalls notwendige, eingriffsbezogene postoperative venöse Thromboseprophylaxe muss an den Tagen, an denen keine „Bridging“-Therapie vorgesehen ist, gegeben werden.
Wiener klinische Wochenschrift 07/2013; 125(13-14). DOI:10.1007/s00508-013-0390-7 · 0.79 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Interruption of an ongoing therapy with vitamin K antagonists (VKAs) is necessary in almost all patients undergoing major surgery. The purpose of the following expert recommendations is to provide easy to use guidance for the periprocedural management of patients on VKAs based on current evidence from the literature. Management of anticoagulation during the time of interruption of VKAs is based on balancing the thromboembolic (TE) risk of underlying conditions against the bleeding risk of the surgical procedure. VKAs should be stopped 3-7days prior to surgery. Low molecular weight heparin (LMWH) is used to cover ("bridge") the progressive pre-operative loss of anticoagulation and the slow post-operative onset of anticoagulant activity of VKAs. Patients with high risk of TE should receive a therapeutic dose of LMWH, patients with a moderate risk of TE should receive half of this dose. Patients with a low risk of TE do not need bridging therapy with LMWH. In case of an uneventful postoperative course, patients with a therapeutic pre-operative dose should be treated post-operatively with the same dose, starting on day 4 in case of major surgery and on day 2 in case of minor procedures. Patients with a half-therapeutic preoperative dose should be treated post-operatively with the same dose, starting on day 3 in case of major surgery and on day 1 in case of minor procedures. Therapy with VKAs should be re-instituted on the second post-operative day based on the preoperative dosage. Procedure-related post-operative thromboprophylaxis should be given irrespective of these recommendations on days without "bridging" anticoagulation.
Wiener klinische Wochenschrift 06/2013; · 0.79 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Despite its widespread availability and known safety and efficacy, a therapy with intravenous thrombolysis is still undergiven. We aimed to identify whether nationwide quality projects-like the stroke registry in Austria-as well as online benchmarking and predefined target values can increase rates of thrombolysis. Therefore, we assessed 6,394 out of 48,462 patients with ischemic stroke from the Austrian stroke registry (study period from March 2003 to December 2011) who had undergone thrombolysis treatment. We defined lower level and target values as quality parameters and evaluated whether or not these parameters could be achieved in the past years. We were able to show that rates of thrombolysis in Austria increased from 4.9 % in 2003 to 18.3 % in 2011. In a multivariate regression model, the main impact seen was the increase over the years [the OR ranges from 0.47 (95 % CI 0.32-0.68) in 2003 to 2.51 (95 % CI 2.20-2.87) in 2011). The predefined lower and target levels of thrombolysis were achieved at the majority of participating centers: in 2011 the lower value of 5 % was achieved at all stroke units, and the target value of 15 % was observed at 21 of 34 stroke units. We conclude that online benchmarking and the concept of defining target values as a tool for nationwide acute stroke care appeared to result in an increase in the rate of thrombolysis over the last few years while the variability between the stroke units has not yet been reduced.
Journal of Neurology 06/2013; 260(9). DOI:10.1007/s00415-013-6964-5 · 3.84 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND AND PURPOSE: Demographic changes, increased awareness of vascular risk factors, better diagnostic, progress in medical care, and increasing primary stroke prevention influence the profile of patients admitted to stroke-units. Changes in patient population and stroke type have important consequences on outcome and management at stroke-units. METHODS: Data from the national database of the Austrian Stroke Unit Registry were analyzed for time-trends in demography, risk factors, cause, and stroke severity. RESULTS: Data of 48 038 ischemic and 5088 hemorrhagic strokes were analyzed. Between 2003 and 2011, median age increased significantly for ischemic strokes from 68 to 71 years in men and from 76 to 78 years in women, respectively.Ischemic stroke patients showed significantly increased rates of hypertension, hypercholesterolemia, and atrial fibrillation. In hemorrhagic strokes an increase for hypercholesterolemia and cardiac diseases other than atrial fibrillation and myocardial infarction were only found in men. A small but significant decrease in stroke severity was found for ischemic strokes from 4 to 3 points on the National Institutes of Health Stroke Scale in men and from 5 to 4 in women, and for hemorrhagic strokes from 9 to 6 points in men and from 9 to 7 in women. Cardioembolic strokes increased slightly, whereas macroangiopathy decreased. CONCLUSIONS: Significant time trends were seen for characteristics of ischemic and hemorrhagic stroke patients admitted to acute stroke-units in Austria. These include trends for older age and toward milder strokes with more cardioembolic causes. This signals a need for increased resources for managing multimorbidity and enabling early mobilization.
[Show abstract][Hide abstract] ABSTRACT: Paradoxical embolism due to a patent foramen ovale (PFO) is a possible cause of ischemic stroke, particularly in young cryptogenic stroke patients. In most cases, however, it is difficult to establish a firm etiological association and the debate about management is ongoing. The Austrian Paradoxical Cerebral Embolism Trial was designed as a prospective, national, multi-center, non-randomized registry to add further data on this topic before the completion of randomized controlled trials. Over 27 months 188 cryptogenic stroke/TIA patients ≤55 years were entered by 15 Austrian stroke units. Contrast transesophageal echocardiography demonstrated a cardiac right-to-left shunt (RLS) in 176 patients; a pulmonary RLS was assumed in 10, and 2 showed both. Ninety-seven (55 %) patients with cardiac RLS underwent interventional treatment, and this was more likely for patients with stroke as index event, a symptomatic infarction on MRI and a large size of PFO. Over 2 years, recurrences occurred at a rate of approximately 1.3 % for stroke and 4.3 % for TIA, and were especially frequent in patients with pulmonary RLS. When comparing outcomes in patients with cardiac RLS there was a trend for fewer recurrences with interventional management (closure: four TIA in four patients vs. medical: three strokes and seven TIA in nine patients; p = 0.066 for events, p = 0.085 for patients). The complication rate was 13.4, and 5.7 % had residual shunting. The possible causes for paradoxical embolism in young patients with cryptogenic stroke appear more variable than usually considered, and other causes than PFO should not be neglected. Interventional treatment of a cardiac RLS may offer a small benefit, but has to be weighed against possible complications and the problem of establishing causality.
Journal of Neurology 08/2012; 260(1). DOI:10.1007/s00415-012-6629-9 · 3.84 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To develop and validate a simple, integer-based score to predict functional outcome in acute ischemic stroke (AIS) using variables readily available after emergency room admission.
Logistic regression was performed in the derivation cohort of previously independent patients with AIS (Acute Stroke Registry and Analysis of Lausanne [ASTRAL]) to identify predictors of unfavorable outcome (3-month modified Rankin Scale score >2). An integer-based point-scoring system for each covariate of the fitted multivariate model was generated by their β-coefficients; the overall score was calculated as the sum of the weighted scores. The model was validated internally using a 2-fold cross-validation technique and externally in 2 independent cohorts (Athens and Vienna Stroke Registries).
Age (A), severity of stroke (S) measured by admission NIH Stroke Scale score, stroke onset to admission time (T), range of visual fields (R), acute glucose (A), and level of consciousness (L) were identified as independent predictors of unfavorable outcome in 1,645 patients in ASTRAL. Their β-coefficients were multiplied by 4 and rounded to the closest integer to generate the score. The area under the receiver operating characteristic curve (AUC) of the score in the ASTRAL cohort was 0.850. The score was well calibrated in the derivation (p = 0.43) and validation cohorts (0.22 [Athens, n = 1,659] and 0.49 [Vienna, n = 653]). AUCs were 0.937 (Athens), 0.771 (Vienna), and 0.902 (when pooled). An ASTRAL score of 31 indicates a 50% likelihood of unfavorable outcome.
The ASTRAL score is a simple integer-based score to predict functional outcome using 6 readily available items at hospital admission. It performed well in double external validation and may be a useful tool for clinical practice and stroke research.
[Show abstract][Hide abstract] ABSTRACT: Die Kriterien für eine gesicherte Indikation zur Operation einer symptomatischen Karotisstenose ergeben sich auf der Basis
randomisierter Studien: Gefordert wird ein klinisches Ereignis passend zur Annahme einer (Thrombo)embolie aus der Karotisstenose
innerhalb der letzten 6 Monate, ein Stenosegrad größer 70% (bezogen auf die distale A. carotis interna) und ein perioperatives
Risiko für Tod oder Schlaganfall kleiner 6%. Eine allgemeine Empfehlung zur Operation einer asymptomatischen Karotisstenose
kann auf der Basis der vorliegenden Studien nicht gegeben werden. Eine asymptomatische Karotisstenose begründet nur in Einzelfällen
die Indikation zu einer operativen Behandlung. Die stentgeschützte Angioplastie (Stent-PTA) ist zum gegenwärtigen Zeitpunkt
ein experimentelles Verfahren, das nur im Rahmen von Studienprotokollen unter Einbeziehung einer Ethikkommission zur Anwendung
kommen sollte. In randomisierten Studien wird derzeit untersucht, ob die Karotisendarterektomie und Stent-PTA bei Patienten
mit symptomatischen Carotisstenosen hinsichtlich des perioperativen Risiskos und der Langzeitergebnisse gleichwertig sind.
Das Embolie-Monitoring mittels transkranieller Doppler-Sonographie scheint vor und während der Durchführung der Stent-PTA
von Bedeutung zu sein.
Carotid endarterectomy (CEA) is proven to be beneficial in symptomatic patients with high-grade carotid stenosis (70% to 99%;
residual lumen as a percentage of the normal distal internal carotid artery) on condition that the peri-operative risk for
mortality and morbidity is less than 6%. A minority of the “leading experts” in North America (48%) and Western Europe (28%)
recommends carotid endarterectomy in asymptomatic patients in general. Most experts suggest to perform surgery only in asymptomatic
patients who are at risk for carotid occlusion in the near future or embolism. At its present state, angioplasty and stenting
is an experimental although promising technique which will have to be compared to carotid endarterectomy. Criteria for duplex
grading of internal carotid stenosis have been established and systematically validated to results of angiography. Pre-surgical
use of angiography will more and more be restricted to selected patients in whom the results of duplex sonography remain inconclusive.
The detection of microemboli with transcranial doppler sonography seems to be of particular importance before and during carotid
angioplasty and stenting.
Der Radiologe 04/2012; 40(9):792-797. DOI:10.1007/s001170050825 · 0.41 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Neurohumoral effects have been suggested to affect kidney function. Stroke is a condition where regulation of the renin-angiotensin system and sympathetic nerve activity are altered.
Renal function as estimated by serum creatinine was analyzed over 1 week in 220 patients after acute ischemic stroke.
In patients with chronic kidney disease defined as those with serum creatinine >1.2 mg/dL at admission (n = 62), renal function transiently improved, measured by a mean decrease of creatinine of 0.34 mg/dL during the first days after stroke. A significant and transient decrease of creatinine was also observed in patients with diabetes (n = 69) or patients with heart failure (n = 89). In both subgroups creatinine decreased by a mean of 0.49 and 0.24 mg/dL, respectively (p < 0.05 for both). In patients with normal renal function at admission, no change in serum creatinine occurred during the first week after stroke. There was no association between stroke severity and creatinine change.
An acute ischemic cerebrovascular event intermittently improves impaired kidney function. The underlying mechanism may involve central regulation of renal function.
[Show abstract][Hide abstract] ABSTRACT: Overexpression of plasma cell membrane glycoprotein-1 (PC-1) inhibits insulin receptor tyrosine kinase activity and thus favours insulin resistance and atherosclerotic vascular disease. Recent findings indicate that the minor variant K121Q in the PC-1 gene confers an increased risk for early myocardial infarction independent of other established risk factors. We hypothesized that genetic variants in PC-1 may also influence the risk for cerebrovascular disease. Aim: Therefore, we assessed the association of the PC-1 K121Q variant in the coding region and a polymorphism (G2906C) in the 3' untranslated region of the PC-1 gene with the risk of stroke. Patients: We analyzed 1014 patients with a history of ischaemic stroke from the Vienna stroke registry and 1001 control individuals without vascular disease. Results, conclusion: Genotype frequencies of both genetic variants were similar in patients and controls in the total study population. By multivariate analysis, no interactions were observed between the PC-1 genotype and established vascular risk factors. However, the PC-1 2906C allele was significantly more frequent in patients who suffered from stroke before the age of 40 years. In these patients the risk for ischaemic stroke was increased four-fold.