Efficacy of anticoagulation for secondar
Anticoagulation in older people with atrial fibrillation and stroke
4. Ferro JM, Falcao I, Rodrigues G et al. Diagnosis of transient
ischemic attack by the nonneurologist: a validation study.
Stroke 1996; 27: 2225–9.
5. Geddes JML, Fear J, Tennant A, Pickering A. Prevalence of
self-reported stroke in a population in northern England.
J Epidemiol Community Health 1996; 50: 140–3.
6. Wade DT. Stroke. In Stevens A, Raftery J, eds. Health Care
Needs Assessment. Oxford: Radcliffe Medical Press, 1994.
7. Wilkinson WE, Heyman A, Burch JG, Ostfield A, Lambarth DR,
Leviton A. Use of a self-administered questionnaire for detection
of transient cerebral ischaemic attacks: survey of elderly persons
living in retirement facilities. Ann Neurol 1979; 6: 40–6.
8. O’Mahony PG, Dobson R, Rodgers H, James OFW, Thomson
RG. Validation of a population screening questionnaire to
assess prevalence of stroke. Stroke 1995; 26: 1334–7.
Age and Ageing 2005; 34: 35–40
doi:10.1093/ageing/afi004
9. Albers GW, Caplan LR, Easton JD et al. Transient ischemic attack
– proposal for a new definition. N Engl J Med 2002; 347: 21.
10. Jones WJ, Williams LS, Meschia JF. Validating the Questionnaire for Verifying Stroke-Free Status (QVSFS) by neurological history and examination. Stroke 2001; 32: 2232–6.
11. Landis JR, Koch GG. The measurement of observer agreement for categorical data. Biometrics 1977; 33: 159–74.
12. Koudstaal PJ, van Gijn J, Staal A, Duivenvoorden HJ. Diagnosis
of transient ischemic attacks: improvement of interobserver
agreement by a check-list in ordinary language. Stroke 1986;
17: 723–8.
Received 12 May 2004; accepted 13 July 2004
Age and Ageing Vol. 34 No. 1 British Geriatrics Society 2005; all rights reserved
Downloaded from ageing.oxfordjournals.org by guest on May 14, 2011
Efficacy of anticoagulation for secondary
stroke prevention in older people with
non-valvular atrial fibrillation:
a prospective case series study
GEORGIOS TSIVGOULIS1, KONSTANTINOS SPENGOS1, NIKOLAOS ZAKOPOULOS2, EFSTATHIOS MANIOS2,
VASSILIOS PEPPES2, KONSTANTINOS VEMMOS2
1
2
Department of Neurology, Eginition Hospital, University of Athens, Greece
Department of Clinical Therapeutics, Alexandra Hospital, University of Athens, Greece
Address correspondence to: K. Spengos, Vas. Sofias 82, 11528 Athens, Greece. Fax: (+30) 210 7216474. Email: spengos@hol.gr
Abstract
Background and purpose: despite large randomised trials that demonstrated the efficacy of oral anticoagulants in the
primary and secondary prevention of stroke in patients with non-valvular atrial fibrillation (AF), anticoagulation therapy
remains largely under-used in older patients, who are at risk of first ever or recurrent stroke. The aim of the present study was
to assess the influence of anticoagulation therapy on long-term prognosis in the oldest old stroke patients with AF after
adjusting for baseline risk factors.
Methods: we evaluated prospectively a consecutive series of 207 older people (>75 years) with AF and first ever ischaemic
stroke. During the follow-up period (mean 88.4 months, range 3–120), the study population was under either oral anticoagulants (n = 72) or aspirin (n = 135). Death and recurrent vascular events (stroke and systemic embolism) were documented.
Statistical analyses were performed by means of the Kaplan–Meier product limit method and the Cox proportional hazards
model.
Results: the cumulative 10 year mortality and recurrence rate were 92.5% (95% CI 85.7–99.3) and 66.1% (95% CI 43.1–
89.1), respectively. Cox regression analysis revealed increasing age, functional dependency at hospital discharge and antiplatelet versus anticoagulation therapy as independent determinants of mortality. Antiplatelet versus anticoagulation therapy was
the sole determinant of vascular recurrence. Anticoagulation was associated with decreased risk of death (hazards ratio (HR)
0.47, 95% CI 0.31–0.72, P = 0.001)) and recurrent thromboembolism (HR 0.31, 95% CI 0.16–0.62, P = 0.002).
35
G. Tsivgoulis et al.
Conclusions: our results suggest that the benefits of anticoagulation for secondary stroke prevention in AF patients extend
to the oldest old. Prospective randomised clinical trials are needed to verify the potential benefit of anticoagulation in such
patients.
Keywords: ischaemic stroke, atrial fibrillation, anticoagulants, elderly, prognosis
Introduction
Subjects and methods
Baseline assessment
This study was based on 1736 first ever stroke patients
consecutively included in the ‘Athens Stroke Registry’
between June 1992 and December 2003. This is a computerised prospective observational databank, gathered in a
university teaching hospital, which provides tertiary care
services to the urban population of Athens. Details of the
stroke population evaluated over the first 5 year period and
exclusion criteria have been previously described [15].
All patients were hospitalised in a five bed acute stroke
unit or a general medical ward. On admission, a physician
specialising in stroke examined all patients. The initial evaluation consisted of a non-contrast brain CT scan, standard
blood tests, a chest X-ray and a 12-lead electrocardiogram.
A second CT scan or brain MRI was performed in most
cases (4–14 days later). During hospitalisation the following
36
Study population
We prospectively evaluated the cases fulfilling all the following criteria: (i) age over 75 years; (ii) electrocardiographically
proven AF in the 12 months preceding the index event; (iii)
first ever IS (347 cases fulfilled the above-mentioned three
criteria); (iv) survival during hospitalisation (78 patients
excluded on the basis of this criterion); (v) no echocardiographic evidence of valvular disease (eight patients excluded
on the basis of this criterion); (vi) no other sources of
cardiac emboli: prosthetic valves, cardiac aneurysm,
myocardial infarction in the preceding 3 months, atrial
myxoma, cardiothoracic ratio >0.65 (11 patients excluded
on the basis of this criterion) [7]; (vii) no contraindications
for OA: repeated falls, chronic alcohol habituation, recurrent syncope, uncontrolled seizure disorder, uncontrolled
hypertension, gastrointestinal or genitourinary bleeding in the
preceding 6 months and daily use of non-steroidal antiinflammatory drugs (21 patients excluded on the basis of this
criterion) [16]. Patients who were transferred to rehabilitation
centres (n = 17) or lost (n = 5) during follow-up were excluded
from further evaluation. The final study population consisted
of 207 patients over 75 years with stroke and AF.
Downloaded from ageing.oxfordjournals.org by guest on May 14, 2011
Non-valvular atrial fibrillation (AF) is a common cardiac
arrhythmia that predisposes to left atrial thrombus formation and carries an increased risk for stroke [1]. Older
people are particularly at high risk because the prevalence of
AF and the risk of AF-associated stroke increase with age
[2, 3]. In people over 75 years, AF is the most important single cause of ischaemic stroke (IS) [4].
Meta-analyses of randomised clinical trials have demonstrated the efficacy of anticoagulation therapy for the primary
prevention of stroke in AF patients [5, 6]. In addition, the
European Atrial Fibrillation Trial (EAFT) has established
the value of anticoagulation for the secondary prevention of
thromboembolic events [7]. Despite the preventive potential
of oral anticoagulants (OA), several studies have reported
that less than 50% of older patients who have clear-cut indications and no contraindications receive OA [8–12].
This low use of warfarin is driven by many factors,
but physicians’ fear of haemorrhage is among the most
important [12–14]. Moreover, older people were significantly under-represented in clinical trials with only 20% of
patients being over 75 [5], although more than 50% of AF
patients were in this age group in population-based trials
[1]. Additional trials that focus on this specific subgroup
of AF patients are warranted to define better the risks and
benefits of antithrombotic therapies [4]. The aim of the
present study was to assess the influence of anticoagulation therapy on long-term prognosis in stroke patients
over the age of 75 and with AF after adjusting for baseline
risk factors.
risk factors were documented: hypertension, diabetes mellitus, atrial fibrillation, hypercholesterolaemia, smoking, coronary artery disease, congestive heart failure and history of
transient ischaemic attacks (TIA) [15]. Atrial fibrillation was
classified as intermittent if electrocardiographic evidence of
sinus rhythm between at least two episodes of AF during
the preceding 12 months was obtained and as constant if
electrocardiographic evidence of sustained AF for more
than 3 weeks without intervening sinus rhythm in the
preceding 12 months was obtained [16].
All patients with no evidence of intracerebral haemorrhage on the first CT scan received aspirin (100–325 mg) on
admission. According to the treating physician’s decision
both in the stroke unit and the general medical wards anticoagulation was initiated 1–4 weeks after ictus in medically
and neurologically stable AF patients after radiographic
exclusion of haemorrhagic infarct transformation. The
remaining patients were treated with aspirin (100–325 mg
daily). The selection of patients for anticoagulation therapy
relied heavily on their compliance, the presence of a motivated family environment and their access to anticoagulation services. The target range for anticoagulation was an
international normalised ratio (INR) of 2.0–3.0 using
adjusted OA doses according to current recommendations
[17]. We used the modified Rankin Scale adapted by the
Oxfordshire Community Stroke Project to classify the functional deficit at hospital discharge [18]. Disabling strokes
were defined as those with Rankin Scores of 2–5 [14, 18].
Anticoagulation in older people with atrial fibrillation and stroke
Follow-up
Statistical analyses
Statistical analysis was performed to compare patients on
OA (group A) and on aspirin (group B) in terms of demographics, pre-existing conditions and functional outcome at
hospital discharge. Dichotomous or categorical variables
were compared with the chi-squared test and continuous
variables were compared with the unpaired t-test or Mann–
Whitney U test as indicated. Continuous data are presented
as mean (SD) and non-continuous data as percentages. The
Kaplan–Meier product limit method was used to estimate
the probability of survival and recurrent vascular events
after 10 years from the index event. To evaluate which
factors contribute to long-term mortality and vascular
recurrence, a univariate Cox’s proportional hazards model
was used. Those factors that contributed to the outcome in
the univariate analyses at P values 75 years) AF patients, the high rate
of intracranial haemorrhage in the anticoagulant-treated
group (1.8% per year) offset the reduction in IS [24]. In
contrast, a meta-analysis of pooled data (223 cases) from
other primary prevention trials found a substantially lower
rate of intracranial haemorrhage in this age subgroup (0.3%
per year) [25]. The documented rate (1.1% per year) in our
cohort lies in the middle of the above-mentioned values.
Downloaded from ageing.oxfordjournals.org by guest on May 14, 2011
Age
(per 10 year increase) 2.72 (1.50–4.91)*
Gender
Male
1.0
Female
1.61 (1.13–2.29)‡
Hypertension
1.14 (0.76–1.71)
Diabetes mellitus
1.09 (0.73–1.62)
Hypercholesterolaemia
0.98 (0.58–1.66)
Smoking
0.69 (0.41–1.17)
Coronary heart disease
1.35 (0.87–2.11)
Pattern of atrial fibrillation
Constant
1.0
Intermittent
0.70 (0.49–1.05)**
Heart failure
1.21 (0.65–2.25)
Previous transient
0.94 (0.47–1.85)
ischaemic attack
Functional outcome at discharge (mRS)
Grade 0–1
1.0
Grade 2–5
2.00 (1.33–3.01)*
Antithrombotic therapy
Antiplatelets
1.0
Anticoagulation
0.45 (0.29–0.70)*
antithrombotic therapy were associated with vascular recurrence on univariate analysis, but only antithrombotic therapy was retained as independent determinant of recurrence
in the multivariate model. The HR associated with OA versus aspirin for long-term mortality and recurrence was 0.47
(95% CI 0.31–0.72, P = 0.001) and 0.31 (95% CI 0.16–0.62,
P = 0.002), respectively.
Anticoagulation in older people with atrial fibrillation and stroke
These patients consequently sustain the largest proportion
of cardioembolic strokes and have the largest relative and
absolute risk reduction in stroke by warfarin compared with
aspirin [1,4]. Our findings indicate that in older patients, the
risk of stroke when not receiving OA appears to outweigh
the risk of intracranial haemorrhage when receiving OA.
The case of wider but judicious use of anticoagulation in
older people is strengthened by this study, which shows that
anticoagulation for secondary stroke prevention is feasible
and effective in such patients.
Key points
• Antiplatelets versus oral anticoagulants are independent
determinants of mortality and vascular recurrence in
older patients with atrial fibrillation. Anticoagulation is
associated with decreased risk of death.
• The benefits of anticoagulation for secondary stroke
prevention in patients with atrial fibrillation extend to the
oldest old.
• Prospective randomised clinical trials are needed to verify
the potential benefit of anticoagulation in older patients.
Acknowledgements
The authors wish to thank Ms Mary Batsara and Mrs Athina
Peppa for their assistance in data collection. There is no
conflict of interests.
References
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This difference could be attributed to the significantly wider
range for the intensity of anticoagulation in SPAF II (upper
INR range 4.5) in comparison with other trials [20, 24].
Our results also indicate that anticoagulation therapy is
independently inversely associated with long-term mortality,
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Apart from anticoagulation therapy, our data identified
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factors are considered [5, 30].
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these were mostly devastating or fatal and in most cases
confirmed by means of hospital records and autopsy findings.
Furthermore, we cannot provide detailed data concerning
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dataset has a number of strengths. The observation period
was longer than in the EAFT and SPAF trials. Although
randomisation was not performed, no significant differences concerning baseline factors were documented
between both groups. Finally, the influence of anticoagulation on long-term prognosis was assessed after controlling
for age, sex, major vascular risk factors, dependency and
comorbidities.
In conclusion, our results suggest that anticoagulation
therapy is an independent predictor of decreased long-term
recurrence and mortality even after taking into account all
known prognostic factors in older people with AF and
recent IS. Although the risk of intracranial haemorrhage
while receiving OA increases with age [24], so does the
stroke risk [23]. People over 75 with AF and IS are considered as high risk by all the risk stratification schemes [1, 23].
G. Tsivgoulis et al.
40
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20. Marine JE, Goldhaber SZ. Controversies surrounding longterm anticoagulation of very elderly patients in atrial fibrillation. Chest 1998; 113: 1115–18.
21. Mant JW, Richards SH, Hobbs FD et al. Midlands Research
Consortium of General Practice. Protocol for Birmingham
4. Ferro JM, Falcao I, Rodrigues G et al. Diagnosis of transient
ischemic attack by the nonneurologist: a validation study.
Stroke 1996; 27: 2225–9.
5. Geddes JML, Fear J, Tennant A, Pickering A. Prevalence of
self-reported stroke in a population in northern England.
J Epidemiol Community Health 1996; 50: 140–3.
6. Wade DT. Stroke. In Stevens A, Raftery J, eds. Health Care
Needs Assessment. Oxford: Radcliffe Medical Press, 1994.
7. Wilkinson WE, Heyman A, Burch JG, Ostfield A, Lambarth DR,
Leviton A. Use of a self-administered questionnaire for detection
of transient cerebral ischaemic attacks: survey of elderly persons
living in retirement facilities. Ann Neurol 1979; 6: 40–6.
8. O’Mahony PG, Dobson R, Rodgers H, James OFW, Thomson
RG. Validation of a population screening questionnaire to
assess prevalence of stroke. Stroke 1995; 26: 1334–7.
Age and Ageing 2005; 34: 35–40
doi:10.1093/ageing/afi004
9. Albers GW, Caplan LR, Easton JD et al. Transient ischemic attack
– proposal for a new definition. N Engl J Med 2002; 347: 21.
10. Jones WJ, Williams LS, Meschia JF. Validating the Questionnaire for Verifying Stroke-Free Status (QVSFS) by neurological history and examination. Stroke 2001; 32: 2232–6.
11. Landis JR, Koch GG. The measurement of observer agreement for categorical data. Biometrics 1977; 33: 159–74.
12. Koudstaal PJ, van Gijn J, Staal A, Duivenvoorden HJ. Diagnosis
of transient ischemic attacks: improvement of interobserver
agreement by a check-list in ordinary language. Stroke 1986;
17: 723–8.
Received 12 May 2004; accepted 13 July 2004
Age and Ageing Vol. 34 No. 1 British Geriatrics Society 2005; all rights reserved
Downloaded from ageing.oxfordjournals.org by guest on May 14, 2011
Efficacy of anticoagulation for secondary
stroke prevention in older people with
non-valvular atrial fibrillation:
a prospective case series study
GEORGIOS TSIVGOULIS1, KONSTANTINOS SPENGOS1, NIKOLAOS ZAKOPOULOS2, EFSTATHIOS MANIOS2,
VASSILIOS PEPPES2, KONSTANTINOS VEMMOS2
1
2
Department of Neurology, Eginition Hospital, University of Athens, Greece
Department of Clinical Therapeutics, Alexandra Hospital, University of Athens, Greece
Address correspondence to: K. Spengos, Vas. Sofias 82, 11528 Athens, Greece. Fax: (+30) 210 7216474. Email: spengos@hol.gr
Abstract
Background and purpose: despite large randomised trials that demonstrated the efficacy of oral anticoagulants in the
primary and secondary prevention of stroke in patients with non-valvular atrial fibrillation (AF), anticoagulation therapy
remains largely under-used in older patients, who are at risk of first ever or recurrent stroke. The aim of the present study was
to assess the influence of anticoagulation therapy on long-term prognosis in the oldest old stroke patients with AF after
adjusting for baseline risk factors.
Methods: we evaluated prospectively a consecutive series of 207 older people (>75 years) with AF and first ever ischaemic
stroke. During the follow-up period (mean 88.4 months, range 3–120), the study population was under either oral anticoagulants (n = 72) or aspirin (n = 135). Death and recurrent vascular events (stroke and systemic embolism) were documented.
Statistical analyses were performed by means of the Kaplan–Meier product limit method and the Cox proportional hazards
model.
Results: the cumulative 10 year mortality and recurrence rate were 92.5% (95% CI 85.7–99.3) and 66.1% (95% CI 43.1–
89.1), respectively. Cox regression analysis revealed increasing age, functional dependency at hospital discharge and antiplatelet versus anticoagulation therapy as independent determinants of mortality. Antiplatelet versus anticoagulation therapy was
the sole determinant of vascular recurrence. Anticoagulation was associated with decreased risk of death (hazards ratio (HR)
0.47, 95% CI 0.31–0.72, P = 0.001)) and recurrent thromboembolism (HR 0.31, 95% CI 0.16–0.62, P = 0.002).
35
G. Tsivgoulis et al.
Conclusions: our results suggest that the benefits of anticoagulation for secondary stroke prevention in AF patients extend
to the oldest old. Prospective randomised clinical trials are needed to verify the potential benefit of anticoagulation in such
patients.
Keywords: ischaemic stroke, atrial fibrillation, anticoagulants, elderly, prognosis
Introduction
Subjects and methods
Baseline assessment
This study was based on 1736 first ever stroke patients
consecutively included in the ‘Athens Stroke Registry’
between June 1992 and December 2003. This is a computerised prospective observational databank, gathered in a
university teaching hospital, which provides tertiary care
services to the urban population of Athens. Details of the
stroke population evaluated over the first 5 year period and
exclusion criteria have been previously described [15].
All patients were hospitalised in a five bed acute stroke
unit or a general medical ward. On admission, a physician
specialising in stroke examined all patients. The initial evaluation consisted of a non-contrast brain CT scan, standard
blood tests, a chest X-ray and a 12-lead electrocardiogram.
A second CT scan or brain MRI was performed in most
cases (4–14 days later). During hospitalisation the following
36
Study population
We prospectively evaluated the cases fulfilling all the following criteria: (i) age over 75 years; (ii) electrocardiographically
proven AF in the 12 months preceding the index event; (iii)
first ever IS (347 cases fulfilled the above-mentioned three
criteria); (iv) survival during hospitalisation (78 patients
excluded on the basis of this criterion); (v) no echocardiographic evidence of valvular disease (eight patients excluded
on the basis of this criterion); (vi) no other sources of
cardiac emboli: prosthetic valves, cardiac aneurysm,
myocardial infarction in the preceding 3 months, atrial
myxoma, cardiothoracic ratio >0.65 (11 patients excluded
on the basis of this criterion) [7]; (vii) no contraindications
for OA: repeated falls, chronic alcohol habituation, recurrent syncope, uncontrolled seizure disorder, uncontrolled
hypertension, gastrointestinal or genitourinary bleeding in the
preceding 6 months and daily use of non-steroidal antiinflammatory drugs (21 patients excluded on the basis of this
criterion) [16]. Patients who were transferred to rehabilitation
centres (n = 17) or lost (n = 5) during follow-up were excluded
from further evaluation. The final study population consisted
of 207 patients over 75 years with stroke and AF.
Downloaded from ageing.oxfordjournals.org by guest on May 14, 2011
Non-valvular atrial fibrillation (AF) is a common cardiac
arrhythmia that predisposes to left atrial thrombus formation and carries an increased risk for stroke [1]. Older
people are particularly at high risk because the prevalence of
AF and the risk of AF-associated stroke increase with age
[2, 3]. In people over 75 years, AF is the most important single cause of ischaemic stroke (IS) [4].
Meta-analyses of randomised clinical trials have demonstrated the efficacy of anticoagulation therapy for the primary
prevention of stroke in AF patients [5, 6]. In addition, the
European Atrial Fibrillation Trial (EAFT) has established
the value of anticoagulation for the secondary prevention of
thromboembolic events [7]. Despite the preventive potential
of oral anticoagulants (OA), several studies have reported
that less than 50% of older patients who have clear-cut indications and no contraindications receive OA [8–12].
This low use of warfarin is driven by many factors,
but physicians’ fear of haemorrhage is among the most
important [12–14]. Moreover, older people were significantly under-represented in clinical trials with only 20% of
patients being over 75 [5], although more than 50% of AF
patients were in this age group in population-based trials
[1]. Additional trials that focus on this specific subgroup
of AF patients are warranted to define better the risks and
benefits of antithrombotic therapies [4]. The aim of the
present study was to assess the influence of anticoagulation therapy on long-term prognosis in stroke patients
over the age of 75 and with AF after adjusting for baseline
risk factors.
risk factors were documented: hypertension, diabetes mellitus, atrial fibrillation, hypercholesterolaemia, smoking, coronary artery disease, congestive heart failure and history of
transient ischaemic attacks (TIA) [15]. Atrial fibrillation was
classified as intermittent if electrocardiographic evidence of
sinus rhythm between at least two episodes of AF during
the preceding 12 months was obtained and as constant if
electrocardiographic evidence of sustained AF for more
than 3 weeks without intervening sinus rhythm in the
preceding 12 months was obtained [16].
All patients with no evidence of intracerebral haemorrhage on the first CT scan received aspirin (100–325 mg) on
admission. According to the treating physician’s decision
both in the stroke unit and the general medical wards anticoagulation was initiated 1–4 weeks after ictus in medically
and neurologically stable AF patients after radiographic
exclusion of haemorrhagic infarct transformation. The
remaining patients were treated with aspirin (100–325 mg
daily). The selection of patients for anticoagulation therapy
relied heavily on their compliance, the presence of a motivated family environment and their access to anticoagulation services. The target range for anticoagulation was an
international normalised ratio (INR) of 2.0–3.0 using
adjusted OA doses according to current recommendations
[17]. We used the modified Rankin Scale adapted by the
Oxfordshire Community Stroke Project to classify the functional deficit at hospital discharge [18]. Disabling strokes
were defined as those with Rankin Scores of 2–5 [14, 18].
Anticoagulation in older people with atrial fibrillation and stroke
Follow-up
Statistical analyses
Statistical analysis was performed to compare patients on
OA (group A) and on aspirin (group B) in terms of demographics, pre-existing conditions and functional outcome at
hospital discharge. Dichotomous or categorical variables
were compared with the chi-squared test and continuous
variables were compared with the unpaired t-test or Mann–
Whitney U test as indicated. Continuous data are presented
as mean (SD) and non-continuous data as percentages. The
Kaplan–Meier product limit method was used to estimate
the probability of survival and recurrent vascular events
after 10 years from the index event. To evaluate which
factors contribute to long-term mortality and vascular
recurrence, a univariate Cox’s proportional hazards model
was used. Those factors that contributed to the outcome in
the univariate analyses at P values 75 years) AF patients, the high rate
of intracranial haemorrhage in the anticoagulant-treated
group (1.8% per year) offset the reduction in IS [24]. In
contrast, a meta-analysis of pooled data (223 cases) from
other primary prevention trials found a substantially lower
rate of intracranial haemorrhage in this age subgroup (0.3%
per year) [25]. The documented rate (1.1% per year) in our
cohort lies in the middle of the above-mentioned values.
Downloaded from ageing.oxfordjournals.org by guest on May 14, 2011
Age
(per 10 year increase) 2.72 (1.50–4.91)*
Gender
Male
1.0
Female
1.61 (1.13–2.29)‡
Hypertension
1.14 (0.76–1.71)
Diabetes mellitus
1.09 (0.73–1.62)
Hypercholesterolaemia
0.98 (0.58–1.66)
Smoking
0.69 (0.41–1.17)
Coronary heart disease
1.35 (0.87–2.11)
Pattern of atrial fibrillation
Constant
1.0
Intermittent
0.70 (0.49–1.05)**
Heart failure
1.21 (0.65–2.25)
Previous transient
0.94 (0.47–1.85)
ischaemic attack
Functional outcome at discharge (mRS)
Grade 0–1
1.0
Grade 2–5
2.00 (1.33–3.01)*
Antithrombotic therapy
Antiplatelets
1.0
Anticoagulation
0.45 (0.29–0.70)*
antithrombotic therapy were associated with vascular recurrence on univariate analysis, but only antithrombotic therapy was retained as independent determinant of recurrence
in the multivariate model. The HR associated with OA versus aspirin for long-term mortality and recurrence was 0.47
(95% CI 0.31–0.72, P = 0.001) and 0.31 (95% CI 0.16–0.62,
P = 0.002), respectively.
Anticoagulation in older people with atrial fibrillation and stroke
These patients consequently sustain the largest proportion
of cardioembolic strokes and have the largest relative and
absolute risk reduction in stroke by warfarin compared with
aspirin [1,4]. Our findings indicate that in older patients, the
risk of stroke when not receiving OA appears to outweigh
the risk of intracranial haemorrhage when receiving OA.
The case of wider but judicious use of anticoagulation in
older people is strengthened by this study, which shows that
anticoagulation for secondary stroke prevention is feasible
and effective in such patients.
Key points
• Antiplatelets versus oral anticoagulants are independent
determinants of mortality and vascular recurrence in
older patients with atrial fibrillation. Anticoagulation is
associated with decreased risk of death.
• The benefits of anticoagulation for secondary stroke
prevention in patients with atrial fibrillation extend to the
oldest old.
• Prospective randomised clinical trials are needed to verify
the potential benefit of anticoagulation in older patients.
Acknowledgements
The authors wish to thank Ms Mary Batsara and Mrs Athina
Peppa for their assistance in data collection. There is no
conflict of interests.
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