From the University Department of Neurology, Charité Medical
School, Berlin, Germany.
Correspondence to Prof Dr K.M. Einhäupl, Neurologische Klinik und Poliklinik der Charité, Medizinische Fakultät der Humboldt-Universität, Schumannstraße 20/21, 10117 Berlin, Germany. E-mail einhaeupl{at}neuro.charite.hu-berlin
Methods—The survey was performed worldwide among 185 neurologists
who are currently leading the discussions of stroke prevention
practices. It contained questions on the use of antiplatelet
agents, oral anticoagulation, and surgery for the prevention of
ischemic stroke. The population of this present
analysis is the two groups of experts from WE (n=73) and NA
(n=48) exclusively.
Results—Of each group, >90% responded to the survey. Nearly all
respondents reported prescribing aspirin in patients at risk of
atherothrombotic stroke, but significant differences between NA and WE
are shown by the recommended doses (P<.0001): aspirin
doses of >500 mg daily are given exclusively by American participants
(36%), whereas doses <200 mg are recommended only in Europe (51%).
Eighty-six percent of American versus 59% of European respondents
reported using ticlopidine as their second choice
(P<.005), and 23% of respondents from WE used warfarin
compared with 5% from NA (P<.05). The reported use of
anticoagulants in patients with atrial fibrillation increased in
accordance with the patient's individual risk of stroke, but
respondents from WE were more reluctant to use anticoagulants in
patients older than 75 years. Relatively higher target international
normalized ratio values were reported by European respondents. Nearly
all participants recommend carotid endarterectomy
in patients with symptomatic carotid stenosis. The
use of carotid endarterectomy in
asymptomatic patients was significantly more common among
responding experts from NA (48% versus 28%; P<.05),
particularly in patients with >95% stenosis (89% versus
53%; P<.0005).
Conclusions—This analysis shows significant differences
in several areas of stroke prevention practices between leading experts
from NA and WE. These differences may be explained partly by divergent
results of trials from the two continents, but in some areas of
controversy currently available trial data are not sufficient to form
an international consensus to guide daily clinical practice.
We conducted a worldwide survey among leading international
experts about their daily management of stroke-prone patients to
evaluate the international acceptance of trial results and the
need for further clinical studies to guide therapeutic decisions. The
results of this survey have been published.9
Since most of the large stroke prevention studies have been performed
in North America (NA) and Western Europe (WE), a direct comparison
between experts from the two continents is of particular interest, and
the number of participants from WE and NA was sufficient to perform a
detailed statistical analysis. The purpose of this present
analysis is to provide an informative and comparative view of
the current practice of leading experts in NA and WE.
The questioned experts were identified in two ways: (1) members of the
editorial and advisory boards of peer-reviewed journals were chosen if
they had published articles primarily focusing on clinical aspects of
stroke therapy indexed in Medline and Current Contents; and
(2) a Medline search was used to identify the national experts for all
countries by selecting all clinical articles on stroke published
between 1983 and February 15, 1996, that had been written by authors of
the respective countries. The authors whose articles were predominantly
centered on stroke prevention or therapy rather than on general or
pathophysiological aspects were chosen as national
experts. If more than one eligible expert was traced to the same
institution, we chose the one with the higher number of clinical
articles, presuming that prevention practice is homogeneous
among physicians of one clinical center.
The data were collected between February and August 1996. A
questionnaire was designed for use in a mail survey. It contained 21
questions on the general use of different treatment strategies and was
divided into four sections: (1) use of antithrombotic agents in
patients with a past history of TIA or minor ischemic stroke of
noncardiogenic origin; questions focused on the choice of agents, the
preferred daily doses, duration of therapy, procedures in case of
inefficacy, and different treatments for women/patients with major
stroke; (2) treatment of patients with nonvalvular AF according
to their age and risk profile; (3) general indications for surgery to
prevent stroke in patients with symptomatic or
asymptomatic arteriosclerotic disease
of major extracranial arteries; and (4) questions to determine the
factors that have been important to the physician for developing
her/his therapeutic concept. The questionnaire can be reviewed on the
Internet (http://www. ukrv.de/ch/neuro/quest.html).
The survey started on February 15, 1996. Nonrespondents were sent two
additional mailings of the questionnaire. All physicians who had not
answered by July 1 were contacted by telephone and were sent a last
questionnaire by fax. The data collection process ended on August 15,
1996.
The frequency distributions of the different reported treatment
strategies were analyzed for both groups separately. The given
percentages of participants who reported using a certain therapy are
related to the number of valid answers (n) to the specific question. If
a question had been omitted or was answered vaguely or if more than one
answer was given, it was regarded as invalid data and did not enter the
statistical analysis. Differences in frequency distribution of
reported therapies between both groups were statistically tested for
significance. The statistical analyses included
cross-tabulations, the Mann-Whitney U and Wilcoxon
rank tests, and the
Antithrombotic Therapy
Asked for their second-choice agent if contraindications, adverse
effects, or recurrent attacks demanded an alternative treatment, 86%
of American (n=43) and 59% of European respondents (n=65) reported
using ticlopidine, whereas 7% and 12%, respectively, reported
prescribing a combination therapy of aspirin and
dipyridamole. Warfarin was the reported second choice
of 23% of WE participants compared with 5% of responding experts from
NA. The overall difference concerning the reported second-choice agents
was significant at P<.01. The comparison of the frequencies
of reported use of the single agents showed significant differences for
ticlopidine (P<.005) and for coumarin
(P<.05).
Regarding the third-choice agent, 78% of NA participants (n=37) named
warfarin, 11% ticlopidine, and 5% aspirin in combination with
dipyridamole. In WE (n=57), 49% of participants
reported using warfarin as third choice, 25% aspirin and
dipyridamole combined, 16% ticlopidine, and 9%
dipyridamole alone. This difference was significant
(P<.01) for the entire spectrum of agents. The comparison
of the frequencies of reported use of the single agents showed
significant differences (P<.05) for coumarin and for the
combination of aspirin and dipyridamole. Aspirin in
combination with warfarin or ticlopidine, and low-dose heparin were
named only once.
The reported aspirin doses ranged from 30 to 1300 mg per day. Fig 1
Regarding the duration of prophylactic treatment, 100% of
American (n=43) and 85% of European (n=66) respondents reported
prescribing their first-choice agent indefinitely, and 14% of European
experts reported prescribing their first-choice agent for 2 to 3 years.
Asked for the treatment of patients who suffered from a major stroke,
approximately two thirds of responding experts in both NA (n=44) and WE
(n=67) said they would not choose a different treatment regimen than in
patients with minor strokes or TIA (68% and 66%, respectively). There
was a statistically significant difference (P<.005) between
the two groups regarding the treatment of women: 25% of American
(n=44) and 6% of European (n=68) respondents do treat women and men
differently. Of the 25% Americans, 73% used ticlopidine in women.
In case of recurrence of cerebral ischemia despite
treatment, approximately one third of responding experts from both NA
(n=44) and WE (n=67) reported increasing the dose of their favorite
agent first (36% and 30%, respectively), whereas 57% and 61%,
respectively, immediately proceed with their second-choice agent.
Respectively, 40% and 37% reported combining different drugs at some
time in the search for an effective therapy, especially aspirin with
warfarin or ticlopidine.
Atrial Fibrillation
The reported frequencies of use of warfarin and aspirin in patients
younger than 75 years show no significant difference between NA and
WE.
Concerning the treatment of patients older than 75 years, the reported
frequency of use of warfarin is higher among respondents from NA,
whereas more European respondents reported using aspirin in these
patients. This difference was significant at P<.05 for
patients of this age with AF only and for patients with
cardioembolism as well as AF.
Respondents from NA recommended target INR values between 1.75 and 3.0.
Of these, 65% reported a target INR between 2.0 and 3.0, 17% reported
a target INR of
Vascular Surgery
The reported use of CEA in asymptomatic patients is
summarized in Fig 2
The reported frequencies of use of CEA in asymptomatic
patients changed according to concomitant characteristics of the
disease. Asked for their management of patients with an
asymptomatic high-grade (>95%) stenosis, 89% of
participants from NA and 53% of WE respondents reported using CEA.
This difference was significant (P<.0005). The fast
progression of the disease was a criterion for operation for more than
half of all respondents from both continents (55% and 58%,
respectively). Forty percent of responding American experts and 24% of
their European colleagues reported recommending surgery in the case of
detected vessel-wall ulceration (not significant at
P>.5).
The majority of experts from both continents (nearly 90% each) agree
in prescribing aspirin for those asymptomatic patients who
do not undergo surgery; the remaining respondents administer warfarin,
ticlopidine, or no treatment.
Asked for their management of patients with a stenosis of the
vertebral artery, 30% of responding experts from NA and 15% of
participants from WE reported considering vascular surgery or
percutaneous transluminal angioplasty. Reported
indications were proximal stenosis of the vertebral artery,
particularly bilateral, vascular malformations, and proven embolism in
the vertebrobasilar area.
Concerning extracranial-intracranial arterial bypass
surgery, 26% of the participating American experts and 14% of their
European colleagues reported using this therapy in a few exceptional
cases.
Our results reflect the ongoing dispute regarding optimal aspirin dose
between some European and American experts published in several
articles and editorials.1 2 3 4 5 Whereas several
neurologists from WE follow the results of low-dose aspirin trials and
argue that these doses are as effective as high doses but cause fewer
side effects,3 5 Barnett et
al4 point to the smaller risk reduction achieved
in low-dose trials (7% to 18%) compared with high-dose trials (25%
to 42%), and Dyken et al1 emphasize that the
increase in side effects is small and does not contraindicate higher
doses if they are more effective. The reported use of lower aspirin
doses among European respondents in our survey might be influenced by
the fact that all low-dose trials have been performed in
Europe.11 12 13 Regional differences exist even
within the continent itself: the use of very low doses (30 to 75 mg)
was mainly reported by respondents from the Scandinavian and Benelux
countries, where the corresponding trials have been
performed.12 13
The arguments presented in these "aspirin wars" are largely
based on indirect and selective comparisons of different trial data,
mini-meta-analyses, or subgroup analyses of individual
studies, and it appears that available trial data are not sufficient to
form an international consensus, although the large
meta-analysis of the Antiplatelet Trialists' Collaboration
found "no appreciable evidence that either a higher aspirin dose or
any other antiplatelet regimen was more effective than medium dose
aspirin in preventing vascular events."14 Our
survey confirms the need for a randomized trial to settle the ongoing
aspirin wars and to determine the optimal aspirin dose against which
any new antiplatelet agent must be tested to obtain indisputable
results.
Although a majority of responding experts from both continents reported
using ticlopidine as their second-choice agent if recurrent attacks
occur, the survey shows a significant difference in the use of
anticoagulants. Almost one fourth of all participating European
neurologists prefer warfarin as second choice compared with only 5%
from NA. This result is surprising because the effectiveness of
anticoagulants in patients with TIA or minor stroke of noncardioembolic
origin is still not proven. Since participants were not asked to
explain why they prefer a certain therapeutic regimen, it can only be
suspected that respondents from WE are more likely to switch to a
different therapeutic principle rather than to try a different
antiplatelet agent. The majority of responding American
neurologists consider warfarin as the third option if patients do not
respond to aspirin and ticlopidine.
A combination of aspirin and dipyridamole was more
frequently found among responding European experts, but this difference
was not significant. Since the now published results of the Second
European Stroke Prevention Study15 had only been
reported to a congress when this survey was
performed,16 an increased use of aspirin and
dipyridamole by European experts may be seen in the
future.
There is no clear scientific evidence that recurrent attacks of
cerebral ischemia necessitate a change of medical treatment,
although this may be common clinical practice. However, one third of
participating experts in both groups reported increasing the dose, and
two thirds reported changing to their second-choice agent if recurrent
cerebral ischemic events occur. The implications of these
results should be viewed critically. The question of whether to
continue the initial antiplatelet agent or switch to a second
antiplatelet drug or even to anticoagulants cannot be answered from
the available published trials. The fact that only one participant from
WE reported continuing the initially chosen treatment may be due to the
fact that "continuation of treatment" was not explicitly named as a
possible answer. We asked the participants how they would proceed if
the chosen therapy was ineffective, and possible answers included
"increase dose," "change to second choice," "combine
different agents," and "others." The phrasing of the possible
answers may have been suggestive, so that a change from the initial
therapy was anticipated.
In this survey, significantly more American respondents (25% versus
only 6% in WE) reported using ticlopidine in women, thereby
questioning the equal efficacy of aspirin for stroke prevention in both
sexes. This difference may be due to the fact that thus far only three
European trials found a significant benefit of aspirin in female
patients with previous TIA or minor
stroke,12 15 17 whereas women did not benefit in
two other studies.11 18 On the other hand,
ticlopidine was effective in men and women in both American ticlopidine
trials.19 20 The large meta-analysis of
the Antiplatelet Trialists' Collaboration,14
which found no difference for aspirin between the two sexes, appears to
have settled this question.
The reported practices of stroke prevention in patients with
nonvalvular AF depended on the patient's age, on concomitant
risk factors (such as hypertension, diabetes, or cardiac disease), and
primarily on the patient's history of cardioembolic events. Several
randomized trials have shown that anticoagulants can reduce the risk of
cardioembolic stroke by approximately 70%, whereas the
prophylactic efficacy of aspirin is
equivocal.21 22 23 Consequently, the reported use
of warfarin generally increased with the increase of the patient's
risk of stroke, whereas the frequency of the use of aspirin decreased
in the same direction, with no difference for patients younger than 75
years. In patients older than 75 years, respondents from WE were less
likely to prescribe anticoagulants, even for high-risk patients with a
previous cardioembolic event. This difference is probably due to
concerns about the safety of anticoagulants in this age group, which
are based on results from Stroke Prevention in Atrial Fibrillation II.
In this trial, a significant increase of bleeding complications,
particularly intracranial hemorrhages, occurred with warfarin
but not with aspirin in patients older than 75
years.23 However, several participants emphasized
that the patient's age is not the main criterion for the decision to
use warfarin, but that other factors such as a history of falls or
bleeds, the patient's competency and mental state, and monitoring
facilities are more crucial.
Overall, responding experts from WE recommended higher intensities of
anticoagulation for all given clinical settings. The highest target INR
value reported by American neurologists was 3.0 and 83% use a target
value between 1.75 and 3.0, whereas nearly 50% of the responding
experts from WE reported target INR values
There was a clear consensus among both groups to recommend CEA for
patients with a severe symptomatic stenosis of the
internal carotid artery. However, we did not explicitly ask for the
method of measurement of the degree of stenosis (North American
Symptomatic Carotid Endarterectomy
Trial or European Carotid Surgery Trial), and the results show a trend
rather than a particular comparable degree of stenosis for
which CEA is recommended.
This clear unanimity was not found for asymptomatic
patients. Almost 50% of all participating experts from NA reported the
use of CEA compared with 28% from WE (P<.05). This
difference was even more impressive concerning the management of
asymptomatic patients with a nearly occluded internal
carotid artery: 89% of American and 53% of European respondents
recommended CEA in these patients (P<.0005). These numbers
reflect the contrary view of the ACAS results by several experts from
NA and WE. The American ACAS trial showed a significant benefit of CEA
in asymptomatic patients with a carotid stenosis
In this survey, participating experts from NA were generally more
likely to use surgical measures for stroke prevention in patients with
a stenosis of either the carotid or the vertebral artery than
their colleagues from WE.
The experts questioned in our survey have access to the same published
clinical studies, and most of them attend the same international
meetings where the results of these trials are discussed and
interpreted. In a scientific discipline, one would therefore expect a
high level of agreement in the interpretation of these studies and
conclusions for clinical practice. We did not investigate several
factors such as the age of the investigator, site of training, size of
clinical practice, or the number of patients actually seen by the
experts during the last year, and we cannot exclude that those factors
may have influenced the divergent treatment recommendations of experts
from both continents. However, it seems unlikely that the significant
differences found in the survey, eg, the different aspirin dosing
policies, are sufficiently explained by those factors. Indeed, if such
factors were of major importance for the reported differences, one
would expect a random distribution of the divergent treatment
recommendations among the experts from both continents. It may be
assumed that the recommended lower aspirin doses in WE and the more
frequent use of carotid surgery in asymptomatic subjects in
NA are at least partly explained by the location where the respective
studies have been performed.
The results of this survey do not report the actual clinical practice
of general practitioners or of primary or secondary health
care centers but report the treatment recommendations of opinion
leaders who define the "dogma" of medical treatment in the field of
stroke prevention. It can be assumed that actual clinical practice may
be further influenced by additional factors such as the physician's
medical specialty, budget issues, and the availability of medical
facilities. Hence, a definite conclusion about the practice cannot be
drawn. Although little comparative data are available, the results of a
recent survey focusing on the general use of stroke prevention
practices among primary care physicians in the United States and the
United Kingdom show similarities to our data27 :
participating British physicians prescribed lower doses of aspirin,
were more reluctant to use warfarin in patients with AF, and less
frequently referred patients with symptoms of carotid stenosis
to surgeons.
In conclusion, the results of this study do not show the real use of
different pharmacological agents for stroke prevention or the real
frequency of CEA for asymptomatic carotid artery
stenosis in both continents but rather reflect the medical
dogma in the field of stroke prevention set by experts in NA and
WE.
Received September 19, 1997;
revision received November 18, 1997;
accepted November 18, 1997.
2.
Hart RG, Harrison MJG. Aspirin wars: the optimal dose
of aspirin to prevent stroke. Stroke. 1996;27:585–587.
3.
Patrono C, Roth GJ. Aspirin in ischemic
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4.
Barnett HJM, Kaste M, Meldrum H, Eliasziw M. Aspirin
dose in stroke prevention: beautiful hypotheses slain by ugly facts.
Stroke. 1996;27:588–592.
5.
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offers only modest protection after cerebral ischaemia. J
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prolonged antiplatelet therapy in various categories of patients.
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© 1998 American Heart Association, Inc.
Original Contributions
Differences in Medical and Surgical Therapy for Stroke Prevention Between Leading Experts in North America and Western Europe
Abstract
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
Appendix 1
References
Background and Purpose—Large
multicenter trials have evaluated the benefit of different medical and
surgical therapies to prevent stroke. However, the application of trial
results to clinical practice remains uncertain for some areas of stroke
prevention and has been discussed passionately among international
experts. As part of a worldwide survey, the purpose of this
analysis was to provide an informative and comparative view of
the current practice of leading experts in North America (NA) and
Western Europe (WE), where most of the large prevention trials have
been performed.
Key Words: aspirin • atrial fibrillation • carotid endarterectomy • North America • stroke prevention • ticlopidine • warfarin • Western Europe
Introduction
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
Appendix 1
References
During the last
decade, many randomized multicenter trials have been performed in the
field of stroke prevention, and spectacular results seemed to have
answered important open questions. However, several of the available
trial results are viewed controversially by leading experts, and there
is an ongoing international discussion in different areas of stroke
prevention, particularly in regard to the optimal dose of aspirin in
patients with minor atherothrombotic stroke or
TIAs1 2 3 4 5 and the use of CEA in
asymptomatic patients.6 7 8
Apparently, even results from large trials with a high level of
significance do not inevitably lead to standardized recommendations for
daily clinical practice.
Subjects and Methods
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
Appendix 1
References
The complete survey was performed worldwide among 185 experts of
stroke therapy and prevention, ie, neurologists who had published
articles on clinical aspects of this topic in peer-reviewed journals
indexed in Medline and Current Contents and are thereby
leading the international or regional discussions. Of these 185
neurologists, 73 were residents of WE (including Northern, Western, and
Southern Europe but excluding Eastern Europe), 48 were practicing in
North America, and the remaining 64 were from South America, Eastern
Europe, Africa, Australia, or Asia. The results of the survey have been
published for the entire population.9 This
present study is a comparative analysis between the two
groups of experts from WE (n=73) and NA (n=48) exclusively. 
2 test.
Results
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
Appendix 1
References
Overall, 92% of questioned NA neurologists (n=44) and 93% of
questioned WE neurologists (n=68) responded to the survey in time and
formed the basis for frequency analysis. Two questionnaires
from Europe arrived after the deadline and could not be considered.
Almost all participating experts in both NA (n=44) and WE (n=65)
reported prescribing aspirin as their first-choice antiplatelet
agent for the prevention of atherothrombotic stroke in patients with a
past history of TIA or minor ischemic stroke of noncardiogenic
origin (96% and 94%, respectively). In NA, two participants (4%)
reported using warfarin in these patients. In WE, three respondents
(4%) reported prescribing aspirin combined with
dipyridamole, and one reported prescribing
ticlopidine. 
shows the frequency distribution of the
reported use of low (30 to 175 mg), medium (200 to 400 mg), and high
(500 to 1300 mg) daily aspirin doses among American and European
respondents. In NA (n=44), medium doses of aspirin was reported by
61%, high doses by 36%, and low doses by 2% of responding experts.
Of 68 Western European participants, 51% recommend low-dose aspirin,
47% medium-dose aspirin, and 2% high-dose aspirin. This difference in
frequency distribution was significant (P<.0001). Of all
respondents, 10 American experts (23%) reported using aspirin doses
>800 mg per day. Of these, 5 experts reported prescribing a dose of
1300 mg daily, and the other 5 preferred doses between 975 and 1200 mg.
The highest dose found among European participants was 500 mg daily,
which was reported by 1 expert. Doses of 
60 mg per day were found
among 7 European experts (10%); 4 of 5 Dutch experts preferred 30 mg
daily. Of 8 European participants who reported using 75 mg of aspirin
per day, 5 were from Sweden and 2 from Great Britain. One American
respondent reported a dose of <300 mg daily (81 mg). The most commonly
reported dose was 300 to 350 mg per day in both NA and WE (61% and
38%, respectively). In WE, nearly one third (29%) prescribed doses of
100 to 175 mg daily.
View larger version (22K):
[in a new window]
Figure 1. Percentages of participants from NA and WE
reporting using low (30 to 175 mg), medium (200 to 400 mg), or high
(500 to 1300 mg) daily doses of aspirin for stroke prevention after
previous atherothrombotic stroke or TIA.
The Table shows the frequency
distribution of the use of warfarin and aspirin according to the
patient's clinical characteristics. In both groups of participants,
the reported use of warfarin generally increased with the increase of
the patient's risk of stroke (AF plus no additional risk; AF plus
concomitant risk factors; AF plus history of
cardioembolism), whereas the frequency of the use of
aspirin decreased in the same direction.
View this table:
[in a new window]
Table 1. Percentages of Participants Reporting Use of Warfarin and
Aspirin in Patients With Nonvalvular AF 2.0, and 18% reported a target INR of 3.0. Among WE
participants, INR values between 1.75 and 3.5 were recommended; 46%
reported a target INR of 
3.0, 46% reported a target INR between 2.0
and 3.0, and 8% reported a target INR of 2.0.
All participants from NA (n=44) and nearly all of their European
colleagues (n=67) (99%) reported recommending CEA for patients with a
symptomatic stenosis of the extracranial portion of
the internal carotid artery. In both NA and WE, the majority of
respondents (84% and 78%, respectively) reported suggesting CEA if
the degree of stenosis is 70%; 7% and 10%, respectively,
recommend the procedure for patients with >80% stenosis, and
again 7% and 10% use it for patients with >60% stenosis.
One European participant does not operate at all, and one American
participant waits for a >90% stenosis. The vast majority of
both groups (approximately 98% each) reported that they also recommend
surgery for patients with an additional stenosis of the
contralateral carotid artery. . Of all American
respondents (n=44), 48% reported recommending CEA in
asymptomatic patients, while 28% of their European
colleagues (n=67) do so. This difference was significant at
P<.05. Within Europe, considerable regional variations were
found: 71% of participants from Southern European countries (n=17)
reported using CEA in asymptomatic patients, whereas only
7% of experts from Northern European countries (n=15) do so. For the
majority of experts from both continents who recommended an operation
to asymptomatic patients, a >80% stenosis is an
indication for surgery (70% of 21 in NA and 63% of 19 in WE). Twenty
percent of the 21 American experts and 16% of the 19 experts from WE
reported operating on patients with >70% stenosis, and 10%
and 21%, respectively, reported operating on patients with >60%
stenosis.
View larger version (25K):
[in a new window]
Figure 2. Percentages of participants from NA and WE
reporting using CEA in asymptomatic patients. General
indicates general use of CEA; fast, use of CEA for fast progressive
stenoses; ulc, use of CEA if ulcerated plaques are present;
and >95, use of CEA for a stenosis >95%.
*P<.05; **P<.0005.
Discussion
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
Appendix 1
References
The results of this survey demonstrate differences in several
areas of medical and surgical stroke prevention between participating
leading neurologists from NA and WE. Although aspirin was the
first-choice antiplatelet agent in patients with a recent TIA or
minor stroke in both groups, recommended doses varied significantly.
Whereas responding European experts only exceptionally (2%) prescribe
aspirin doses 500 mg, 36% of American participants prefer a dose of
500 mg. In contrast, doses <200 mg daily are used by 51% of
European respondents but by only 2% of their American colleagues. This
dissent in dosing policies is substantial and differs from the results
of the only survey among leading experts that has been published thus
far: Hennerici10 reported a "secret
consensus" in favor of low and very low aspirin doses among 44
members of the Advisory/Editorial Boards of Cerebrovascular Diseases.
Only two experts reported preferring a daily dose of 500 mg, whereas
42 (95%) recommended doses of 325 mg and 9 experts (20%)
recommended a dose of 100 mg. However, this survey did not examine
regional differences, and the consensus might be due to a smaller
number of participants from NA. 3.0. This different
practice corresponds to recommendations in the respective continents:
the Fourth American College of Chest Physicians Consensus Conference on
Antithrombotic Therapy recommended target INR values of 2.0 to
3.0,24 whereas the European Atrial Fibrillation
Trial study group proposed an optimal oral anticoagulation between 2.0
and 3.9.25 60% and a surgical risk <3%.26 In view of
these results, a Multidisciplinary Consensus Statement from the
American Heart Association recommended CEA for asymptomatic
patients,6 whereas some European experts point to
the little absolute risk reduction achieved by CEA for
asymptomatic carotid stenosis and its lack of
cost-effectiveness7 and recommend caution in the
interpretation of ACAS results.8
Selected Abbreviations and Acronyms
ACAS
=
Asymptomatic Carotid Atherosclerosis Study
AF
=
atrial fibrillation
CEA
=
carotid endarterectomy
INR
=
international normalized ratio
NA
=
North America
TIA
=
transient ischemic attack
WE
=
Western Europe
Appendix 1
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
Appendix 1
References
List of Participants
H.P. Adams, F. Aichner, G.W. Albers, P. Amarenco, D.C. Anderson,
G.P. Anzola, K. Asplund, J. Bamford, H.J.M. Barnett, J. Biller, S.
Blecic, J. Bogousslavsky, M.G. Bousser, G. Boysen, L.M. Brass, J.P.
Broderick, T. Brott, C. Candelise, L.R. Caplan, A. Chamorro, M.I.
Chimowitz, R. Cote, B.M. Coull, J. De Reuck, L. Deecke, G.J. Del Zoppo,
V. Demarin, H. Diener, M.N. Diringer, B. Dobkin, M.L. Dyken, W.M.
Feinberg, J.M. Ferro, C. Fieschi, M. Fisher, R. Fogelholm, A. Freire
Goncalves, A.J. Furlan, N. Futrell, C. Gandolfo, L.B. Goldstein, M.
Goldstein, P.B. Gorelick, J. Grotta, V. Hachinski, W. Hacke, E.C.
Haley, M.J.G. Harrison, R.G. Hart, A. Hartmann, W.D. Heiss, C.M.
Helgason, M. Hennerici, D.B. Hier, A. Hijdra, M. Hommel, P. Humphrey,
M. Hutchinson, B. Indredavik, D. Inzitari, A. Jovicic, L. Kalra, L.J.
Kappelle, D. Karacostas, C.S. Kase, M. Kaste, Ch. Kessler, P.J.
Koudstaal, E. Kumral, G. Landi, G.L. Lenzi, S.R. Levine, D. Leys, A.
Lindgren, J. Lodder, A. Lowenthal, J.L. Marti-Vilalta, P. Marx, J.-L.
Mas, J. Matias-Guiu, H.P. Mattle, Prof Metz, J.P. Mohr, J.W. Norris, B.
Norrving, R. Nyberg-Hansen, T.S. Olsen, J.M. Orgogozo, C. Papageorgiou,
S.J. Phillips, E.C. Raps, E.B. Ringelstein, D. Russell, R.L. Sacco,
P.A.G. Sandercock, O. Saribas, J. Shannon, D.G. Sherman, J. Sivenius,
L. Thomassen, J.F. Toole, J. van Gijn, E. Varela-de Seijas, S.
Vorstrup, N.G. Wahlgren, C.P. Warlow, P.A. Wolf, and F.M. Yatsu. Four
questionnaires were sent back anonymously, and their senders could
therefore not be listed here.
References
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
Appendix 1
References
1.
Dyken ML, Barnett HJM, Easton JD, Fields WS,
Fuster V, Hachinski V, Norris JW, Sherman DG. Low-dose aspirin and
stroke: `it ain't necessarily so.' Stroke. 1992;23:1395–1399.
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