Does prior use of aspirin affect outcome in ischemic stroke?

Ischaemic stroke despite antiplatelet therapy: Causes and outcomes

BACKGROUND

Ischaemic stroke may occur despite antiplatelet therapy (APT). We aimed to investigate frequency, potential causes and outcomes in patients with ischaemic stroke despite APT.

METHODS

In this cohort study, we enrolled patients with imaging-confirmed ischaemic stroke from the Swiss Stroke Registry (01/2014-07/2022). We determined the frequency of prior APT, assessed stroke aetiology (modified TOAST classification) and determined the association of prior APT with unfavourable functional outcome (modified Rankin Scale score 3-6) and recurrent ischaemic stroke at 3 months using regression models.

RESULTS

Among 53,352 patients, 27,484 (51.5%) had no prior antithrombotic treatment, 17,760 (33.3%) were on APT, 7039 (13.2%) on anticoagulation and 1069 (2.0%) were on APT + anticoagulation. In patients with a history of ischaemic stroke/TIA (n = 11,948; 22.4%), 2401 (20.1%) had no prior antithrombotic therapy, 6594 (55.2%) were on APT, 2489 (20.8%) on anticoagulation and 464 (3.9%) on APT + anticoagulation. Amongst patients with ischaemic stroke despite APT, aetiology was large artery atherosclerosis in 19.8% (n = 3416), cardiac embolism in 23.6% (n = 4059), small vessel disease in 11.7% (n = 2011), other causes in 7.4% (n = 1267), more than one cause in 6.3% (n = 1078) and unknown cause in 31.3% (n = 5388). Prior APT was not independently associated with unfavourable outcome (aOR = 1.06; 95% CI: 0.98-1.14; p = 0.135) or death (aOR = 1.10; 95% CI: 0.99-1.21; p = 0.059) at 3-months but with increased odds of recurrent stroke (6.0% vs 4.3%; aOR 1.26; 95% CI: 1.11-1.44; p < 0.001).

CONCLUSIONS

One-third of ischaemic strokes occurred despite APT and 20% of patients with a history of ischaemic stroke had no antithrombotic therapy when having stroke recurrence. Aetiology of breakthrough strokes despite APT is heterogeneous and these patients are at increased risk of recurrent stroke.

The effects of cardiovascular risk factor combined anti-platelet therapy and the risk of cerebrovascular events in patients with T2DM in an urban community over 96-months follow-up: The Beijing communities diabetes study 19

OBJECTIVE

We investigated the prognostic significance of metabolic risk scores and aspirin with respect to cerebrovascular events.

METHODS

A total of 25 communities of diabetic patients were enrolled in Beijing Community Diabetes Study (BCDS) from 2008. 3413 patients with T2DM in BCDS have complete screening data, including blood glucose, blood pressure, lipid profiles and anti-platelet therapy, which were assigned metabolic score (MS) and add up to the total metabolic score (TMS). According to the total metabolic score (TMS), the patients were divided into four equal groups: Group 1 (24 < TMS < 40), Group 2 (40 < TMS < 47), Group 3 (47 < TMS < 55) and Group 4 (55 < TMS < 87). After 96 months, patients were followed-up to assess the long-term effects of the multifactorial interventions.

RESULTS

During 96-months follow-up, a total of 91 cerebrovascular events occurred, including acute cerebral infarction, acute cerebral hemorrhage and transient ischemic attack (TIA). The incidence of cerebrovascular events was higher in the Group 4 than in the Group 1. In Cox multivariate analyses, there are significant differences in incidences of cerebral infarction events among the four groups during the 96-months follow-up. Cox proportional hazards analysis revealed that, HbA1c (p ≤ 0.001), systolic pressure (p ≤ 0.001), aspirin free treatment (P = 0.0023) are independent predictor for cerebrovascular events in diabetic patients.

CONCLUSIONS

This study indicates that total metabolic score (TMS) influences the incidence of cerebrovascular events in diabetic patients. In addition to good control of blood glucose, blood pressure and lipid profiles, anti-platelet therapy is important for the prevention of cerebrovascular events in T2DM.

TRIAL REGISTRATION

ChiCTR-TRC-13003978, ChiCTR-OOC-15006090.

Antiplatelet therapy as a modulator of stroke aetiology: a meta-analysis

AIMS

Antiplatelet therapy reduces the incidence of ischaemic stroke. Platelet-mediated thrombosis contributes variably to the major subtypes of stroke as defined by the TOAST criteria: large artery atherosclerosis (LAA), cardioembolic (CE) and small vessel occlusion (SVO). The effect of antiplatelet therapy on the incidence of each subtype is unknown and is the subject of this meta-analysis.

METHODS

Electronic databases were searched for articles comparing the effect of antiplatelet therapy on the incidence of stroke according to aetiological subtype. Studies containing subjects prescribed anticoagulant therapy or solely investigating subjects with atrial fibrillation were excluded. Pooled odds ratios (ORs) were calculated using a fixed effects model.

RESULTS

Nine studies were included (n = 5739). In patients who had an ischaemic stroke, pre-event antiplatelet therapy was associated with significantly decreased incidence of LAA (OR 0.88, 95% CI 0.79, 0.99; P = 0.026), increased incidence of CE (OR 1.23, 95% CI 1.08, 1.41; P = 0.002) and no effect on SVO (OR 0.99, 95% CI 0.88, 1.11; P = 0.806). Concordant non-significant trends were observed in primary prevention populations (n = 751): LAA (OR 0.81, 95% CI 0.57, 1.15; P = 0.240), CE (OR 1.29, 95% CI 0.89, 1.87; P = 0.179) and SVO (OR 0.99, 95% CI 0.73, 1.36; P = 0.970). Subgroup analysis of aspirin monotherapy (n = 3786) demonstrated a significant reduction in LAA (OR 0.87, 95% CI 0.76, 1.00; P = 0.046), but non-significant effects on the incidence of CE (OR 1.17, 95% CI 0.99, 1.39; P = 0.068) and SVO (OR 1.04, 95% CI 0.91, 1.20; P = 0.570). Probability of publication bias was low (P > 0.05).

CONCLUSIONS

Antiplatelet therapy preferentially reduces the incidence of LAA stroke compared with CE and SVO subtypes.

Does aspirin-induced oxidative stress cause asthma exacerbation?

Aspirin-induced asthma (AIA) is a distinct clinical syndrome characterized by severe asthma exacerbations after ingestion of aspirin or other non-steroidal anti-inflammatory drugs. The exact pathomechanism of AIA remains unknown, though ongoing research has shed some light. Recently, more and more attention has been focused on the role of aspirin in the induction of oxidative stress, especially in cancer cell systems. However, it has not excluded the similar action of aspirin in other inflammatory disorders such as asthma. Moreover, increased levels of 8-isoprostanes, reliable biomarkers of oxidative stress in expired breath condensate in steroid-naïve patients with AIA compared to AIA patients treated with steroids and healthy volunteers, has been observed. This review is an attempt to cover aspirin-induced oxidative stress action in AIA and to suggest a possible related pathomechanism.

Heart dysfunction in patients with acute ischemic stroke or TIA does not predict all-cause mortality at long-term follow-up

BACKGROUND

Despite heart failure being a substantial risk factor for stroke, few studies have evaluated the predictive value of heart dysfunction for all-cause mortality in patients with acute ischemic stroke, in particular in the elderly. The aim of this study was to investigate whether impaired heart function in elderly patients can predict all-cause mortality after acute ischemic stroke or transient ischemic attack (TIA).

METHODS

A prospective long-term follow-up analysis was performed on a hospital cohort consisting of n = 132 patients with mean age 73 ± 9 years, presenting with acute ischemic stroke or transient ischemic attack, without atrial fibrillation. All patients were examined by echocardiography during the hospital stay. Data about all-cause mortality were collected at the end of the follow-up period. The mean follow-up period was 56 ± 22 months.

RESULTS

In this cohort, 58% of patients with acute ischemic stroke or TIA had heart dysfunction. Survival analysis showed that heart dysfunction did not predict all-cause mortality in this cohort. Furthermore, in multivariate regression analysis age (HR 5.401, Cl 1.97-14.78, p < 0.01), smoking (HR 3.181, Cl 1.36-7.47, p < 0.01), myocardial infarction (HR 2.826, Cl 1.17-6.83, p < 0.05) were independent predictors of all-cause mortality.

CONCLUSION

In this population with acute ischemic stroke or TIA and without non-valvular atrial fibrillation, impaired heart function does not seem to be a significant predictor of all-cause mortality at long-term follow-up.

Prestroke antiplatelet therapy and early prognosis in stroke patients: the Dijon Stroke Registry

BACKGROUND AND PURPOSE

Previous antiplatelet therapy (APT) in cardiovascular prevention is common in patients with first-ever stroke. We aimed to evaluate the prognostic value of APT on early outcome in stroke patients.

METHODS

All first-ever strokes from 1985 to 2011 were identified from the population-based Stroke Registry of Dijon, France. Demographic features, risk factors, prestroke treatments and clinical information were recorded. Multivariate analyses were performed to evaluate the associations between pre-admission APT and both severe handicap at discharge, and mortality at 1 month and 1 year.

RESULTS

Among the 4275 patients, 870 (20.4%) were previously treated with APT. Severe handicap at discharge was noted in 233 (26.8%) APT users and in 974 (28.7%) non-users. Prestroke APT use was associated with lower odds of severe handicap at discharge [adjusted odds ratio (OR): 0.79; 95% confidence interval (CI): 063-1.00; P = 0.046], non-significant better survival at 1 month [adjusted hazard ratio (HR): 0.87; 95% CI: 0.70-1.09; P = 0.222] and no effect on 1-year mortality (HR: 0.94; 95% CI 0.80-1.10; P = 0.429). In stratum-specific analyses, APT was associated with a lower risk of 1-month mortality in patients with cardioembolic ischaemic stroke (HR: 0.65; 95% CI: 0.43-0.98; P = 0.040).

CONCLUSIONS

APT before stroke was associated with less severe handicap at discharge, with no significant protective effect for mortality at 1 month except in patients with cardioembolic stroke. No protective effect of APT was observed for mortality at 1 year. Further studies are needed to understand the mechanisms underlying the distinct effects of prior APT observed across the ischaemic stroke subtypes.

Comparative evaluation of treatment with low-dose aspirin plus dipyridamole versus aspirin only in patients with acute ischaemic stroke

BACKGROUND

Previous studies have suggested that pre-stroke treatment with low-dose aspirin (A) could reduce the severity of acute ischaemic stroke, but less is known on the effect of pre-stroke treatment with a combination of aspirin and dipyridamole (A + D) and post-stroke effects of these drugs. The aim of the present study was to evaluate the effect of this drug combination on acute and long-term prognosis of ischaemic stroke.

METHODS

Patients without atrial fibrillation admitted to the stroke unit with acute ischaemic stroke (n = 554) or TIA (n = 108) were studied during acute hospital care and up to 12 months after discharge from hospital.

RESULTS

Prior to acute stroke 62 patients were treated with A + D while 247 patients were treated with A only. No beneficial effects of the combination A + D compared to A only were noted on stroke severity and/or acute in-hospital mortality. However, survival analysis by Cox-proportional hazard model demonstrated lower 12-months all-cause mortality in patients discharged with A + D (n = 275) compared with patients on A only (HR, 0.52; CI, 0.32-0.86; p = 0.011; n = 262) after adjusting for age, baseline NIHSS, previous stroke, previous myocardial infarction and type 2 diabetes. We also noted a tendency towards lower all-cause mortality at 3 months with use of A + D, but this was not statistically significant (p = 0.12).

CONCLUSIONS

Pre-stroke treatment with a combination of low-dose A + D does not reduce the severity of acute stroke, nor does it reduce the acute in-hospital mortality. However, treatment with A + D at discharge from hospital is seemingly associated with lower long-term mortality compared with A only, contrary to the results from previous randomised studies. However, our results must be interpreted with extreme caution considering the non-randomised study design.

[Non-taking oral antithrombotic agents in patients with ischemic stroke]

BACKGROUND

In clinical practice, secondary prevention in patients with ischemic stroke (IS) needs to be continued permanently; however, antithrombotic agents are sometimes stopped by clinicians or the patients themselves. The rate of non-taking oral antithrombotic agents was evaluated in IS patients.

METHODS

266 consecutive patients (154 men and 112 women; age, 73.6 +/- 11.5 years) with first-ever acute IS were studied. Patients with transient ischemic attack (TIA) were also included. Emboligenic heart diseases, frequency of past stroke, oral antithrombotic agent use just before IS, and secondary prevention were evaluated.

RESULTS

The number of past strokes was 0 in 182 cases (68.4%), 1 in 66 cases (24.8%), 2 in 14 cases (5.3%), 3 in 3 cases (1.1%), and 9 in 1 case (0.4%; 3 times with stroke, and 6 times with TIA). There were 42 cases (15.8%) with TIA, 47 (17.7%) with lacunar infarction, 69 (25.9%) with atherothrombotic infarction, 62 (23.3%) with cardioembolic infarction, 23 (8.7%) with other types of infarction, and 23 (8.7%) with stroke of unknown etiology. Although 15-26% of patients with their first IS had taken antithrombotic agents just before IS, about 40% of the patients with a previous IS history were not taking antithrombotic agents just before their recurrent IS.

CONCLUSION

About 40% of the patients with recurrent IS were not taking antithrombotic agents at the time of their recurrent IS; had they been taking antithrombotic agents at the time, the recurrent IS might have been prevented. Clinicians must recognize the importance of antithrombotic agents in patients with IS, and patients must continue to take antithrombotic agents permanently.

Reduced severity of strokes in patients with silent brain infarctions

BACKGROUND

Silent brain infarctions (SBIs), leukoaraiosis (LA), and microbleeds (MBs) are ischaemic silent radiologic abnormalities that act as predictors of subsequent strokes. This study investigated the independent effect of silent radiologic abnormalities on initial stroke severity and short-term outcome.

METHODS

A consecutive series of patients who had their first ischaemic stroke within 72 h of symptom onset were included. Demographic and clinical characteristics were collected on admission, and magnetic resonance imaging was performed to evaluate the ischaemic lesion, SBI, LA, and MB. Factors potentially associated with lower initial stroke severity (admission NIH Stroke Scale 0-5) and good short-term outcome (discharge NIH Stroke Scale 0-5, modified Rankin Scale 0-1) were validated by multivariate analysis.

RESULTS

Silent brain infarctions were noted in 82 (45%) of the 182 patients. Although there were no statistically significant differences in stroke subtypes and lesion location, univariate analysis revealed that patients with SBI had reduced stroke severity (P = 0.005) and infarction volume (P = 0.001). After adjusting for covariates, the presence of SBI was independently associated with lower stroke severity and good short-term outcome when the NIH Stroke Scale was used as dependent variable (OR 3.368, 95% CI 1.361-8.332, P = 0.009; OR 3.459, 95% CI 1.227-9.755, P = 0.019, respectively). However, the presence of SBI lost significance when the discharge-modified Rankin Scale was used as dependent variable (P = 0.058).

CONCLUSION

Amongst silent radiologic abnormalities, SBI was the only predictor of reduced stroke severity and infarct volume. Silent brain infarction deserves more attention in evaluating stroke severity.

Differential effect of previous antiplatelet use on stroke severity according to stroke mechanism

BACKGROUND AND PURPOSE

The effect of previous antiplatelet use on stroke severity is controversial. We assume that this controversy is attributable to its difference according to the stroke mechanism.

METHODS

Using a prospective stroke registry, patients who were hospitalized because of ischemic stroke and had relevant lesions on MRI were selected. Patients who were using anticoagulants or whose stroke subtype was categorized as stroke of other determined etiology or undetermined etiology were excluded. Baseline stroke severity was measured using the National Institutes of Health Stroke Scale scores at presentation and was compared between no previous antiplatelet users and previous antiplatelet users with stratification by stroke subtypes.

RESULTS

Among the 1622 patients, a total of 490 (30.2%) patients reported use of an antiplatelet within 1 week of stroke onset. The baseline National Institutes of Health Stroke Scale score showed no difference between the nonantiplatelet and antiplatelet groups by crude comparison. However, the interaction between previous antiplatelet use and stroke subtype was significant (P=0.023) in a multivariable analysis; when the study subjects were stratified by stroke subtype, the difference in baseline National Institutes of Health Stroke Scale between the nonantiplatelet and platelet groups was significant in the large artery atherothrombosis group but not in those with cardioembolism and small-vessel occlusion before and after adjustments.

CONCLUSIONS

Our study suggests that the reduction of initial stroke severity in the previous antiplatelet users may differ by stroke mechanism.

Reduction of disability after stroke is a more informative predictor of long-time survival than initial disability status

PURPOSE

Few studies have evaluated the roles of reducing disability after stroke in predicting survival. This study aimed to investigate the effects of improvement in the Barthel Index (BI) and other prognostic factors on survival in patients with first-time noncardioembolic ischemic stroke.

METHOD

BI effectiveness was defined as the improvement of BI between initial stroke (within 3 days) and 2 months after stroke. Cox regression analysis and Kaplan-Meier methods were used to evaluate the predictive roles of various prognostic factors.

RESULTS

A total of 111 patients were enrolled. Mean age at the time of stroke was 68 (+ or - 11.2) years. Median follow-up time was 77.4 months. Mean initial BI was 36.1 (+ or - 28.5) and mean BI effectiveness was 46.9 + or - 29.0. Overall, 55 deaths (49.5%) of the cohort were ascertained. The BI effectiveness had significant effects on long-time survival while initial BI was not a significant predictor. Higher BI effectiveness led to lower risk of mortality (hazard ratio = 0.44, 95% CI 0.24 - 0.80, p = 0.007). Elder age was correlated with poor survival (overall p = 0.006). Subjects in the eldest age group (> or = 70 years) showed a significant elevated risk for death (hazard ratio = 3.42, 95% CI 1.18 - 9.92). There was a trend indicating that the smaller the lesion size, the more favourable the prognosis (overall p = 0.057).

CONCLUSIONS

BI effectiveness in the first 2 months after first-time noncardioembolic stroke was more informative than initial disability status for predicting long-time mortality. It highlights the potential benefit in maximizing functional performance in patients with stroke.

Pretreatment with aspirin and etiology of first-ever ischemic stroke in young and middle-aged patients

BACKGROUND

There are very limited data on the influence of pretreatment with aspirin (ASA) on the etiology of subsequent first-ever ischemic stroke.

MATERIALS AND METHODS

Five hundred ninety eight patients 65 years old or younger with first-ever ischemic stroke either pretreated (N=167) or not treated with aspirin (N=431) participated.

RESULTS

The mean age was 56.5+/-6.0 years for patients treated with ASA and 53.1+/-8.9 years for those not treated (p<.0001). All major vascular risk factors except smoking were significantly more frequent among the patients pretreated with aspirin. Logistic regression analysis adjustments for age, gender, and major vascular risk factors revealed an overall significant effect (p<0.0001) of aspirin treatment on the distribution of stroke etiologies. Subsequent separate analyses on stroke etiology subtypes indicated that the incidence of small vessel disease (SVD) related strokes was significantly reduced by pretreatment with aspirin (OR=0.63). Logistic regression analysis showed no influence of aspirin on the likelihood of a favorable or unfavorable outcome, as expressed by Rankin scale.

CONCLUSION

Pretreatment with ASA has significant influence on the distribution of etiologies of first-ever ischemic stroke in young and middle-aged patients, when the immediate functional stroke outcome is not influenced by ASA pretreatment.

Secondary stroke prevention: inside the vessels and beyond

Cerebral ischaemic stroke is frequently a relapsing, if not chronic, disease. Its incidence is age-dependent, and with the ageing of society the need for effective therapies increases. This review considers current and alternative hypotheses underlying secondary prevention of stroke. Currently, secondary stroke prevention is widely practiced with aspirin (acetylsalicylic acid), a drug that has been in use for more than 100 years. Newer drugs such as ticlopidine and clopidogrel have subsequently been developed, but their efficacy barely surpasses that of aspirin. Other drugs used in secondary stroke prevention include HMG-CoA reductase inhibitors and antihypertensive agents. The endovascular paradigm has shaped the thinking of secondary stroke prevention, and aspirin, ticlopidine and clopidogrel are known as 'platelet inhibitors'; however, their pharmacological and clinical effects are not fully explained within the platelet paradigm. Moreover, in recent years, reduction of stroke incidence has also been observed with HMG-CoA reductase inhibitors, regardless of their lipid-lowering effects. Hence, current understanding needs to be supplemented by considering mechanisms beyond platelet inhibition. Evidence has shown that aspirin, ticlopidine and clopidogrel share neuroprotective properties not explained by the platelet paradigm and that are reminiscent of a preconditioning effect. This neuroprotective mechanism is also shared with HMG-CoA reductase inhibitors.

Does Prior Aspirin Use Reduce Stroke Mortality?

BACKGROUND

Millions of people around the world regularly consume aspirin, but its value in determining stroke severity is still not clear. It has been stated that prior aspirin use might reduce the severity of ischemic stroke by reducing the size of fibrin-platelet emboli or by ameliorating platelet hyperaggregability that occurs in the microcirculation. However there are only few large studies focusing on the early outcome of stroke patients including both ischemic stroke and primary intracerebral hemorrhage patients with prior aspirin therapy.

REVIEW SUMMARY

We retrospectively analyzed the medical records of 2509 consecutive stroke patients who were hospitalized in the 2nd Neurology Clinic of Haydarpaşa Numune Education and Research Hospital, Istanbul, Turkey, during the period of 1993-2003. We compared the early mortality rates in the patients with prior aspirin use versus the patients without. Of the patients without prior aspirin use, 20.1% died during the first 3 weeks of the stroke, while only 11.5% of the patients with prior aspirin use died during the same period. The difference in early mortality rate between 2 groups was extremely significant (P = 0.0008). Logistic regression analysis indicated that aspirin use was a significant (P < 0.01) and independent predictor of early stroke mortality.

CONCLUSION

Daily low dose (100-300 mg) aspirin has a protective effect in reducing the risk of early death in stroke.

Prior use of antithrombotic agents and neurological functional outcome at discharge in patients with ischemic stroke

BACKGROUND

Studies in experimental animals have suggested that antithrombotic agents may have a neuroprotective effect after an ischemic injury. The aim of this study was to analyze the effect of prior use of antithrombotic agents (antiplatelets or anticoagulants) on neurological functional outcome in patients with acute ischemic stroke.

SUBJECTS AND METHODS

Consecutive patients included in the Perugia Stroke Registry were considered for this analysis. Neurological functional outcome was evaluated at discharge using the modified Rankin Scale (mRS >or= 3 disabling stroke).

RESULTS

Of the 1921 patients included in the analysis (mean age 76.3 +/- 12.5 years; 53% males), 662 (34.5%) were on antithrombotic treatment (581 antiplatelets, 71 anticoagulants and 10 antiplatelets associated with anticoagulants). One hundred and twenty-two patients (6.4%) died in hospital; at discharge 712 patients (37.1%) were disabled and 1,087 patients (56.6%) were non-disabled. Fifty-four (44.3%) of the deceased patients and 270 (37.9%) of disabled patients were on antithrombotic treatment, while 338 (31.1%) non-disabled patients were taking antithrombotic agents. From multivariate analysis, age and stroke severity were associated with an adverse outcome. Male gender, dyslipidemia, stroke due to small vessel disease and no history of previous stroke were associated with an improved outcome, while no correlation was found between prior use of antithrombotic agents and outcome (mortality odds ratio; OR = 1.32, 95% confidence interval; CI 0.85-2.04; P = 0.20, mortality or disability OR = 0.95, 95% CI 0.72-1.25; P = 0.80).

CONCLUSION

Prior use of antithrombotic agents does not improve the functional outcome in patients with acute ischemic stroke.

Previous Use of Aspirin and Baseline Stroke Severity

Background and Purpose— Some studies suggest that taking aspirin regularly at the time of the onset of stroke reduces stroke severity. Other studies suggest the converse (ie, that previous aspirin therapy is associated with greater stroke severity). We sought to examine this question among the patients enrolled in the International Stroke Trial (IST).

Methods— Analysis of the associations of reported use of aspirin in the 3 days before randomization in IST with baseline stroke severity (as assessed by stroke clinical syndrome, predicted outcome at 6 months, and observed outcome at 6 months). We adjusted analyses for confounding factors.

Results— We excluded those patients who were first scanned after trial entry and were found to have an intracerebral hemorrhage as the cause of the stroke leading to randomization. We performed analyses for all treatment groups combined. For the 17 850 patients with ischemic stroke, data at baseline and follow-up were available for 100% and 99%, respectively. Among these patients, 3820 (21.4%) reported previous aspirin use. Previous aspirin use appeared, in univariate analyses, to be associated with greater baseline stroke severity, more severe stroke syndrome, and, in control subjects, worse observed outcome at 6 months. However, after adjustment, these associations were no longer significant.

Conclusions— In this large prospective and complete data set, we found no evidence of any association of previous aspirin use with baseline stroke severity. The analyses suggest that previously reported positive and negative associations may well have been attributable to the play of chance in small samples, confounding or other biases, rather than a biological effect of aspirin.

Prior therapy with antiplatelet agents is not associated with outcome in patients with acute ischemic stroke/TIA

BACKGROUND AND PURPOSE

It is unclear whether prior therapy with antiplatelet agents (APA) is associated with a better outcome in patients with acute ischemic cerebrovascular events.

METHODS

Within a multi-center cross-sectional study, nested in a cohort we analyzed the relation between prior therapy with APA and stroke severity in 1643 patients with acute ischemic stroke or TIA. Clinical severity of the vascular event was evaluated by the National Institutes of Health Stroke Scale on admission (NIHSS1) and after 1 week (NIHSS2). By means of analysis of variance we analyzed a possible association of APA with stroke severity and interactions regarding stroke severity between APA and other clinical measures.

RESULTS

475 patients (29 %) received aspirin prior to the cerebrovascular event, 51 patients (3 %) ticlopidine or clopidogrel and 26 patients (1.6%) aspirin combined with extended release dipyridamole. 66% (1091) of patients did not take any antiplatelet medication. Neither the NIHSS1 nor the NIHSS2 nor the change of stroke severity between these time points (NIHSS1- NIHSS2) was associated with prior APA medication. We did not find significant interactions between APA use and clinical measures regarding stroke severity.

CONCLUSIONS

Our results do not indicate that prior therapy with APA is associated with a better outcome in acute ischemic cerebrovascular events. There were no interactions found with other features that were associated with stroke severity.

Progressing stroke with neurological deterioration in a group of Israeli elderly

Progressing stroke with neurological deterioration (PSND), i.e., neurological deterioration of patients during the first days following a stroke, although not an infrequent event, has hitherto been addressed only by few studies. This is the first investigation conducted in Israel with the aim to determine its prevalence and characteristics. Data regarding 140 patients with first ever stroke were collected prospectively between May 1999 and October 2000. All patients underwent a thorough daily neurological examination over the first 7 days, using the Canadian Neurological Scale. Most (90%), patients had hemiparesis, with dysarthria, aphasia and dysphagia being the most frequent associated neurological deficits. Thirty percent of the patients were on anti-aggregant therapy prior to the stroke. The prevalence of PSND was 23%. The 1-month in-hospital death rate of these PSND patients was 31%. Univariate analysis showed that previous anti-aggregant therapy, Parkinson's disease (PD), obesity, hyperlipidemia, and presence of aphasia were significantly more frequent in the PSND group. In addition, these patients arrived earlier to the emergency room. However, logistic regression analysis showed that only PD and obesity could possibly be considered as predictors for development of PSND. The prevalence as well as the death rate of PSND in this group of Israeli elderly is within the range reported in the literature. However, prior anti-aggregant treatment and PD, are here reported for the first time as associated conditions. Future research will possibly clarify the links between these entities and PSND.

Outcomes in the management of atrial fibrillation: clinical trial results can apply in practice

BACKGROUND

The benefits of antithrombotic therapy in chronic atrial fibrillation (AF) have been established in clinical trials, but there is a paucity of data on outcomes in practice.

AIMS

The objective was to establish a large ongoing database of patients with non-valvular AF, to enable the accurate determination of clinical outcomes.

METHODS

A retrospective review of the medical records for consecutive patients who had AF documented on electrocardiogram at the major teaching hospital in Tasmania between 1 January 1997 and 30 June 1999 was performed. An extensive range of demographic and clinical variables was recorded for all patients with chronic or paroxysmal non-valvular AF.

RESULTS

The 505 patients (60% males) included in the database had a median age of 76 years. According to risk stratification criteria, 79% of the patients with previously diagnosed chronic or paroxysmal AF had a high risk of developing stroke at the time of admission to hospital care. However, only one-third (34%) of these patients were receiving warfarin (or warfarin plus aspirin), with almost one-quarter (24%) receiving no antithrombotic agent. The annual incidence of ischaemic strokes was 3.4% (1.5-6.4%; 95% CI) when taking warfarin, compared to 7.0% (5.2-9.4%) for patients not taking warfarin and 7.8% (5.4-11.1%) for patients taking aspirin. The annual incidence of bleeding complications in patients taking warfarin was 14.2% (10.0-19.5%) overall and 3.4% (1.5-6.4%) for major bleeds. In patients not taking warfarin, the overall annual incidence of bleeds was 8.4% (6.3-10.9%) and 3.9% (2.5-5.7%) for major bleeds.

CONCLUSIONS

Warfarin is underused in patients with AF. In clinical practice, warfarin confers a similar stroke risk reduction to that observed in trials, with an increase in incidence of only minor bleeding complications. Aspirin did not appear to reduce the risk of stroke.