Age- and sex-specific rates of leukoaraiosis
in TIA and stroke patients
Michela Simoni, MD,
Linxin Li, MSc
Nicola L.M. Paul,
Basil E. Gruter, BMed
Ursula G. Schulz, PhD
Wilhelm Ku ¨ker, FRCR
Peter M. Rothwell,
Objective: To determine any sex differences in age-specific prevalence or severity of leukoarai-
osis, a marker of white matter ischemia, in population-based and clinic cohorts of TIA/stroke and
in a systematic review of the literature.
Methods: Age-specific sex differences were calculated for both CT and MRI in the Oxford Vascu-
lar Study (OXVASC) and in an MRI-based clinic cohort. We pooled odds ratios (ORs) for leukoarai-
osis in women vs men from published studies by fixed-effect meta-analysis, stratified by patient
characteristics (stroke vs nonstroke) and CT vs MRI.
Results: Among 10 stroke studies (all CT-based), leukoaraiosis was most frequent in women (OR ?
1.42, 95% confidence interval [CI] 1.27–1.57, p ? 0.0001), with little heterogeneity between
studies (p ? 0.28). However, no such excess was seen in 10 reports of nonstroke cohorts (0.91,
0.67–1.24, p ? 0.56). Moreover, excess leukoaraiosis in women on CT-imaging in OXVASC
(1.38, 1.15–1.67, p ? 0.001) was explained by their older age (age-adjusted OR ? 1.01, 0.82–
1.25, p ? 0.90). Leukoaraiosis was more severe in older (?75) women (CT-1.50, 1.14–1.97, p ?
0.004 in OXVASC; MRI-1.70, 1.17–2.48, p ? 0.006 in OXVASC and clinic cohort). However,
leukoaraiosis was independently associated with early mortality (hazard ratio ? 1.46, 1.23–
1.73, p ? 0.0001), suggesting that comparisons in older age groups will be biased by prior pre-
mature death of men with leukoaraiosis. Sex differences in severity of leukoaraiosis were not
addressed in previous studies.
Conclusions: Previously reported excess leukoaraiosis in women with TIA/stroke is likely to be
confounded by age and apparently greater severity in older women is likely to be biased by prema-
ture death in men with leukoaraiosis. Neurology®2012;79:1215–1222
CI ? confidence interval; OR ? odds ratio; OXVASC ? Oxford Vascular Study.
Onset of coronary artery disease is delayed in women compared to men,1,2and women have a
lower prevalence of peripheral and carotid artery disease, particularly before 75 years of age.3
However, the overall age-specific incidence of stroke differs much less between the sexes,4the
lifetime risk of stroke is similar in men and women,5,6and stroke in women appears to be more
severe and to lead to more disability than in men.7,8This greater relative susceptibility to stroke
than to coronary artery disease and the increased severity of stroke in women are unexplained,
but could be due to a greater susceptibility to microvascular cerebral ischemia. Women have
been reported to have a higher prevalence and severity of leukoaraiosis than men in some
studies9–12and a higher progression rate of leukoaraiosis by longitudinal MRI studies,13,14
although not all studies have confirmed this difference.15–17To clarify whether leukoaraiosis is
more prevalent or more severe in women than in men, or if the previously observed differences
might be due to confounding by age, or be secondary to competing risk of earlier vascular death
in men, we did a systematic review of the literature on leukoaraiosis and its association to sex,
From the Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, UK.
Study funding: The Oxford Vascular Study is funded by the UK Medical Research Council, the National Institute of Health Research (NIHR), the
Stroke Association, the Dunhill Medical Trust, the NIHR Biomedical Research Centre, Oxford, and the Wellcome Trust. Dr. Ursula G. Schulz is
funded by an NIHR Clinician Scientist Fellowship.
Go to Neurology.org for full disclosures. Disclosures deemed relevant by the authors, if any, are provided at the end of this article.
See page 1208
Correspondence & reprint
requests to Dr. Rothwell:
Copyright © 2012 by AAN Enterprises, Inc.
and studied brain imaging in patients in a
population-based study on stroke and TIA
(Oxford Vascular Study [OXVASC]) and in
an independent TIA-clinic cohort.
METHODS Systematic review. For our systematic review
of the literature we searched 2 main medical search engines,
Medline and Embase (Medline 1950 to present date, Embase
1980 to present date), up to January 4, 2011. We used the terms
leukoaraiosis or white matter changes and matched with the
terms old age/aged, hypertension/high blood pressure, high cho-
lesterol/hypercholesterolemia, cigarette smoking, ischemic heart
disease, alcohol intake/alcohol consumption, diabetes mellitus,
stroke, gender/sex, atrial fibrillation, peripheral vascular disease,
dementia, carotid artery stenosis/disease. For the purpose of this
article, we only considered studies reporting the association be-
tween sex and leukoaraiosis. There was no restriction by lan-
guage of publication.
We calculated pooled odds ratios (ORs) by fixed effect meta-
analysis (if heterogeneity between studies was p ? 0.1 and other-
wise by random effects, and p values with the ?2test) for
presence of leukoaraiosis in women vs men for the studies report-
ing these data. We grouped the studies according to imaging
used (CT or MRI), the mean age of their population, and the
study setting (stroke patients vs nonstroke patients).
Population-based study. The OXVASC study is a
population-based study of all acute vascular events in a popula-
tion of 91,000 individuals registered with 63 primary care physi-
cians in 9 general practices in and around Oxford, UK. Methods
of OXVASC have been reported previously.1,4In brief, multiple
overlapping methods of “hot” pursuit were used to achieve near-
complete ascertainment of all individuals with TIA or stroke.
These included an urgent neurovascular clinic to which partici-
pating general practitioners and the local accident and emer-
gency department send all individuals with suspected TIA or
stroke whom they would not normally admit to hospital; daily
assessment of admissions to the medical, stroke, neurology, and
other relevant hospital wards; and daily searches of the local acci-
dent and emergency department attendance register. To not
miss patients who presented late, were referred to other services,
or were not referred to secondary care, we also performed
monthly computerized searches of family doctor diagnostic cod-
ing, hospital discharge codes, and all cranial and carotid imaging
studies performed in local hospitals. Patients are followed up for
10 years after the entry event. Follow-up visits include blood
pressure check and a questionnaire on general health, recurrent
events, medication, and neuropsychological tests at 1 and 6
months and 1, 5, and 10 years. Follow-up is complete for all
patients for mortality via centralized death certification records
and 5-year follow-up is available in over 95% of patients either
by face-to-face follow-up or follow-up via their family doctor.
Consecutive patients with TIA or stroke (ischemic or hemor-
rhagic) assessed for OXVASC between April 1, 2002, and April
30, 2010, were included. The only exclusion criterion was lack
of availability of adequate brain imaging. Leukoaraiosis was pro-
spectively and independently coded by a neuroradiologist and by
an experienced neurologist. Assessments were made blind to
clinical data. Large cortico-subcortical strokes, definite subcorti-
cal lacunar lesions (well-delineated, oval or rounded, measuring
1.5 cm or less, or with the same signal intensity than CSF), and
obvious tumors or cysts were excluded from the evaluation.
However, less clearcut lacunar infarctions or demyelinating le-
sions in the context of more diffuse leukoaraiosis could not be
reliably excluded by means of our visual assessment.
Leukoaraiosis was graded according to the following:
1. The ARWMC scale18for both CT and MRI, rating 5 differ-
ent regions in both hemispheres according to a 0–3 score. We
used the total score derived from this scale and categorized it
into absent (0), mild (1 to 5), moderate (6 to 10), and severe
(over 10) leukoaraiosis.
2. A qualitative scale (“Oxford scale”) based on the severity score
(absent, mild, moderate, or severe) of the Blennow scale19for
CT scans, and a modified version of the Fazekas scale,20con-
sidering periventricular and deep white matter lesions alto-
gether, for MRI scans.
The neuroradiologist only applied the Oxford scale, while
the neurologist applied both the ARWMC scale and the Ox-
MRI scans were performed on a 1.5-T Philips Achieva scan-
ner, and CT scans on a Toshiba, Aquilion 64, 64-slice scanner.
The MRI sequences chosen for evaluation were the transverse T2
and the coronal fluid-attenuated inversion recovery. This latter
was only available in coronal view, according to the clinical
protocol applied in our hospital, and therefore it was mainly
used to support and clarify the T2 findings.
Clinic cohort. We also studied MRI scans from a population
of 766 consecutive ischemic strokes or TIA seen in a TIA/Stroke
clinic in the Stoke-Mandeville Hospital, near Oxford, from pa-
tients who underwent MRI scan (1.5-T Siemens Symphony sys-
tem) as part of their routine clinical investigation. These scans
had been rated by means of the ARWMC scale by an experi-
enced observer. Combination with the 496 scans rated with the
same scale from OXVASC gave a total number of 1,262 MRI
scans, and the same analyses on the association of leukoaraiosis
to sex were repeated.
Reliability studies. Within the OXVASC cohort, the inter-
rater agreement on presence and severity of leukoaraiosis on CT
was assessed by ? statistics in a subset of 996 consecutive cases
and for MRI on 100 cases. We also performed an agreement
study between CT and MRI in the 416 patients who had had
both modalities of imaging, using the SAS software to calculate
both simple and weighted ?.21
Mandeville and the OXVASC raters was calculated on a sample
of 130 consecutive scans.
Statistical analyses. We calculated age- and sex-specific rates
ences in presence of leukoaraiosis in 3 different age strata (?55,
55–74, ?75) after further adjustment for age as a continuous vari-
moderate-severe vs none-mild leukoaraiosis; and severe vs no, mild,
and moderate leukoaraiosis. Multivariate logistic regression analyses
were performed with presence of leukoaraiosis as outcome variable
age and multiple vascular risk factors (hypertension, previous CVA,
ischemic heart disease, diabetes mellitus, atrial fibrillation, periph-
eral vascular disease, current smoking, hyperlipidemia, carotid ste-
nosis ?50% on either side).
We determined the association between CT-detected leu-
koaraiosis and risk of death in all OXVASC patients and in those
aged ?75 years in a Cox regression analysis.
All analyses were performed using SPSS version 15.
Neurology 79 September 18, 2012
Standard protocol approvals, registrations, and patient
consents. The OXVASC study was approved by the local re-
search ethic committee, and all the patients signed an informed
consent at entry in the study. Approval was obtained from the
local research ethics committee for the TIA-clinic cohort.
RESULTS Our systematic review identified 33 po-
tentially eligible studies, but only 19 (14 based on
CT and 5 on MRI) reported data on presence of
leukoaraiosis stratified by sex. Meta-analysis of data
from these 19 studies showed excess leukoaraiosis in
women (OR 1.19, 95% confidence interval [CI]
1.08–1.33, p ? 0.03), but there was significant (p ?
0.0001) heterogeneity between studies. When strati-
fied by type of study population (figure 1), the excess
leukoaraiosis in women was only seen in TIA and
stroke cohorts (1.42, 1.28–1.57, p ? 0.0001), with
no sex difference in the nonstroke studies (0.91,
0.67–1.24, p ? 0.56), which included healthy sub-
jects, community-dwelling people, patients from
neurology or general medicine clinics, from de-
mentia clinics, and from geriatric or neurology
hospital wards. Although the nonstroke studies
were generally small, these 2 estimates were signif-
icantly different (p ? 0.006). Indeed, the fre-
quency of leukoaraiosis was lower in women vs
men in those nonstroke studies that used MRI
(0.70, 0.56–0.86, p ? 0.001). All studies in TIA/
stroke populations were CT-based.
The OXVASC patients comprised 2,124 subjects
(1,127 female) with age ranging from 21.9 to 99.6
years (mean ? 73.8; SD ? 13.4). Women were sig-
nificantly older than men (75.7 vs 71.5, p ? 0.001).
Patients had been recruited following ischemic stroke
(1,069), cerebral or ocular TIA (791), intracerebral
hemorrhage (109), subarachnoid hemorrhage (67),
and uncertain stroke or retinal artery occlusion (88).
Brain imaging was available for review in 1,890
(89.0%) of 2,124 patients. The most common rea-
Figure 1 Meta-analysis of studies identified by a systematic review of the published literature on the prevalence of leukoaraiosis
stratified by sex
Pooled odds ratios for difference in prevalence of leukoaraiosis between sexes are shown. The studies have been stratified according to patient setting
(stroke vs nonstroke patients), and according to the type of imaging used (CT or MRI). See supplemental data at www.neurology.org for e-references. CI ?
confidence interval; OR ? odds ratio.
Neurology 79 September 18, 2012
sons for nonimaging were death prior to or shortly
after arrival at hospital, events occurring abroad, and
ocular ischemia only. Of the 1,890 patients studied,
988 (52.3%) were women and the sex difference in
age remained (75.3 vs 71.3, p ? 0.001).
We reviewed 2,306 scans from the 1,890 patients
(1,777 CT and 529 MRI, with 416 patients having
both; table e-1 on the Neurology®Web site at
www.neurology.org). The inter-rater agreement on
presence of leukoaraiosis in 996 consecutive cases
imaged by CT and rated by the Oxford scale was
moderate to good (? ? 0.64, 0.59–0.69, for pres-
ence of any leukoaraiosis, and 0.58, 0.55–0.62 for
severity). The inter-rater agreement on presence of
leukoaraiosis in 100 consecutive cases imaged by
MRI and rated by the Oxford scale was also good
(? ? 0.78, 0.65–0.90 for presence and 0.66, 0.56–
0.76 for severity of leukoaraiosis). In the 416 patients
who had both CT and MRI, agreement between in-
dependent assessments made on the different modal-
ities was not significantly less than the interobserver
reproducibilities of either modality alone (table 1).
Table 1Agreement study between CT and MRI evaluated by the same observer, on a total of 416 OXVASC
patients investigated with both modalitiesa
? for severity (0–3 scale)
95% CI Weighted ?
?0.00010.570.45–0.69 0.69 0.59–0.790.01
?0.0001 0.610.53–0.68 0.72 0.66–0.78
Abbreviations: CI ? confidence interval; OXVASC ? Oxford Vascular Study.
aThe ? results are given according to patients’ age groups.
Table 2 Differences between sexes in baseline clinical characteristics in the OXVASC study and in the
OXVASC cohort Stoke-Mandeville cohort
F (942)M (835)pb
F (240)M (289)pb
F (351) M (415)pb
78.2; 11.674.2; 11.6
66.5; 15.0 65.2; 13.20.31 71.6; 12.3 69.5; 11.8 0.02c
557 (59.3)445 (53.4) 0.01c
116 (48.3) 145 (49.8)0.79 200 (57.3)247 (60.4)0.42
121 (12.8) 101 (12.1)0.67 18 (7.5)17 (5.8)0.49 35 (10)46 (11.2)0.64
151 (16.3)194 (23.5)
25 (10.5) 51 (17.6)0.03c
47 (13.6)87 (21.4)
115 (12.2)114 (13.7) 0.40 28 (11.7)43 (14.8)0.31 44 (12.5)68 (16.4) 0.15
159 (16.9)177 (21.2)0.02c
17 (7.1) 28 (9.6)0.35 35 (10.1)38 (9.3)0.71
46 (4.9)78 (9.4)
10 (4.2)20 (6.9)0.19 8 (2.3)24 (6.0)0.02c
119 (12.9)127 (15.5)0.1339 (16.5)55 (19)0.4949 (14.1)98 (23.9)
243 (26.7)226 (27.7) 0.67 70 (30.6)85 (29.6) 0.85108 (39.3) 132 (38.3)0.80
77 (13.1)104 (17.7)0.04c
14 (7.9)24 (10.5)0.40 25 (11.7) 43 (16.2)0.19
527 (55.9)400 (47.9)
135 (56.3)163 (56.4)1.00 223 (63.5) 236 (56.9)0.07
OR (95% CI)
0.99 (0.70–1.40)0.971.32 (0.99–1.77) 0.06
OR (95% CI)
1.01 (0.82–1.25) 0.900.89 (0.60–1.32)0.56 1.15 (0.83–1.60) 0.39
OR (95% CI)
0.84 (0.65–1.09) 0.180.74 (0.46–1.19) 0.221.14 (0.68–1.91)0.62
Abbreviations: CI ? confidence interval; OR ? odds ratio; OXVASC ? Oxford Vascular Study.
aMean age is reported in years; SD, while all the other variables are reported as number of patients with the condition (% of
total). Fully adjusted means adjusted for age and for all the other vascular risk factors listed in the table.
Neurology 79 September 18, 2012
For more detail on the intra and inter-rater reliability
studies, see table e-2.
Leukoaraiosis appeared to be more frequent in
women than in men in those patients imaged by CT
in OXVASC (1.38, 1.15–1.67, p ? 0.001), but
women imaged with CT were older than men im-
aged with CT and when we adjusted the association
for age there was no longer any excess leukoaraiosis in
women (adjusted OR ? 1.01, 0.82–1.25, p ? 0.90)
(table 2 and table e-1). Moreover, in OXVASC pa-
tients imaged by MRI, in whom the males and fe-
males were of similar age, there was no sex difference
in the frequency of leukoaraiosis (table 2 and table
e-1). On both CT and MRI, age was the most pow-
erful predictor of presence of leukoaraiosis (OR per
10 years ? 2.16, 1.96–2.59, p ? 0.001 for CT;
2.59, 1.96–2.83, p ? 0.001 for MRI).
We also stratified analyses by age in 10-year bands
from age 55 (figure 2 shows grading according to the
ARWMC scale; see figure e-1 for grading according
to the Oxford scale). Leukoaraiosis was reported
more frequently on MRI than on CT, particularly in
the younger age groups, but there was little consis-
tent sex difference in frequency with either modality.
However, subcategorization by severity of leukoarai-
osis (ARWMC scale) showed a trend toward more
severe leukoaraiosis in women above 75 years of age,
both on CT and MRI (figure 2, table 3) in OXVASC
and on the merged MRI cohort from OXVASC and
the clinic cohort from Stoke Mandeville (OR for se-
vere leukoaraiosis in women vs men in the composite
MRI cohort: 2.79, 1.63–4.79, p ? 0.0001; figure 2.
To determine whether leukoaraiosis might be as-
sociated with an increased risk of premature death
and hence a competing-risks bias due to earlier death
in men compared with women, we determined the
association between the presence of leukoaraiosis on
CT at entry in OXVASC and time to death in a Cox
regression analysis, also including age, sex, and hy-
pertension as covariates. Leukoaraiosis was a signifi-
cant independent predictor of death (hazard ratio
1.46, 95% CI 1.23–1.73, p ? 0.0001). This associa-
tion remained when analysis was confined to patients
younger than 75 years (1.53, 1.08–2.18, p ? 0.02).
DISCUSSION Clinical onset of coronary artery dis-
ease and peripheral vascular disease is delayed in
women compared with men, but stroke incidence
differs much less.1One possible explanation is that
women are predisposed to cerebral ischemia, which
might be reflected in a greater frequency of leu-
koaraiosis, as has been reported previously in some
studies.9–12However, not all studies have found this
sex difference, and given an absence of published
leukoaraiosis is rated according to the ARWMC scale. Numbers of patients in each category are
Neurology 79September 18, 2012
data from MRI-based studies in patients with TIA
or stroke, we determined sex differences in fre-
quency and severity of leukoaraiosis using both
CT and MRI in a population-based TIA/stroke
incidence study, a clinic cohort, and a systematic
review of the literature.
We found that the apparent excess of leukoarai-
osis in women with TIA/stroke was confounded by
age, with no sex difference on CT or MRI after ad-
justing or stratifying by age. We also found good
inter- and intrarater reliability of assessment of leu-
koaraiosis by both imaging modalities.
We did find that leukoaraiosis was more severe in
women than men at older ages. This finding was
consistent on both CT and MRI and in the
population-based cohort and clinic cohort. This sex
difference could in theory reflect an increased suscep-
tibility of white matter to ischemia in older women,
but it is more likely to be an artifact due to sex differ-
ences in premature death, i.e., men who survive to
their 80s and 90s are a more highly selected group
than are women of the same age. In the OXVASC
cohort of imaged patients reported here, for example,
there were 242 women aged over 85 years, but only
112 men. In other words, about 130 more men than
women born in the same years had already died.
Even if the presence or severity of leukoaraiosis were
only weakly associated with premature death (e.g., a
relative increase in mortality of 10%), it would be
enough to account for the sex differences that we
have observed in older age groups. In fact, the associ-
ation that we observed between leukoaraiosis and risk
of subsequent death in the OXVASC cohort was
stronger. The association between leukoaraiosis and
increased mortality has been reported in other stud-
ies, either in the general population22,23or in stroke
In patients under the age of 75 years, on the other
hand, the numbers of men and women are almost
identical (441 men vs 357 women), with much less
potential for bias due to premature death, and we
found no sex difference in leukoaraiosis. There was a
trend for leukoaraiosis to be more severe in men than
women under the age of 65, but the numbers were
too small for us to be able to draw any conclusion.
Our study has some potential shortcomings. First,
we used semiquantitative methods to assess leu-
koaraiosis severity and our observations were mainly
based on CT scans. However, despite the fact that
reproducibility of rating scales is influenced by the
Table 3Odds ratios for prevalence of different degrees of leukoaraiosis in women vs men, according to age,
in the OXVASC cohort and in the merged OXVASC and Stoke-Mandeville populationa
Age, y LeukoaraiosisImaging
OXVASC and Stoke-Mandeville
OR 95% CIp OR 95% CIp
AnyCT 0.52 0.17–1.590.250———
MRI 0.83 0.33–2.12 0.7001.040.53–2.060.904
Moderate/severe CT 1.720.10–29.5 0.710———
MRI0.46 0.08–2.730.395 3.030.87–10.610.083
SevereCT NA NA NA———
MRI NA NANA 0.58 0.05–6.680.666
AnyCT0.97 0.68–1.39 0.880———
MRI 1.25 0.70–2.220.5460.96 0.68–1.35 0.809
Moderate/severeCT 0.710.45–1.14 0.154———
MRI 0.52 0.26–1.030.060 0.860.58–1.28 0.460
MRI0.65 0.22–1.92 0.4311.130.52–2.46 0.751
Any CT1.200.85–1.70 0.299———
MRI 1.030.46–2.34 0.941 1.44 0.90–2.290.130
Moderate/severe CT 1.280.97–1.690.087———
MRI2.06 0.97–4.40 0.062 2.79b
Abbreviations: CI ? confidence interval; OR ? odds ratio; OXVASC ? Oxford Vascular Study.
aLeukoaraiosis was rated with the ARWMC scale both on CT and MRI. Odds ratios are also adjusted for age as continuous
variable in order to minimize the effect due to age within single age stratum.
Neurology 79 September 18, 2012
nature of the scale itself and by the expertise of the
raters,26,27we found good intra- and inter-rater re-
producibility for both our CT and MRI evaluations.
Moreover, although CT scans have a lower sensitivity
for detection of white matter lesions when compared
with MRI, CT-detected white matter changes are
clinically relevant,28and have good neuropathologic
validity.29,30The concordance of our results between
the MRI cohorts in our study and between the MRI
and CT is reassuring.
Second, not all white matter changes represent
chronic ischemia. We might occasionally have in-
cluded demyelinating or vasculitic lesions or previous
focal ischemic lesions, as these are not always possible
to distinguish from leukoaraiosis by means of visual
evaluation. However, we believe that this would be
unlikely to have resulted in any major bias. Third, in
the systematic review, we were only able to identify
CT-based studies in stroke populations, while the
studies in other settings were based both on CT and
on MRI. However, we also report the largest single-
center stroke-based MRI cohort so far to address sex
differences in leukoaraiosis.
Overall, therefore, we consider that our findings
are unbiased and reliable. The association between
presence of leukoaraiosis and female sex can be ex-
plained by the strong association of leukoaraiosis to
age and by the over-representation of female sex in
the older patients with TIA and stroke. The greater
severity of leukoaraiosis in older women is most
likely an artifact due to greater risk of premature
death in men with leukoaraiosis. We have found no
evidence to support the hypothesis that women have
a greater susceptibility to white matter ischemia than
Michela Simoni, MD, MRCP: study concept and design, acquisition of
data, draft and revision of the manuscript, statistical analysis, and inter-
pretation of data. Linxin Li, MSc: revision of the manuscript content,
acquisition of data. Nicola L.M. Paul, MRCP: revision of the manuscript
content, acquisition of data. Basil E. Gruter, BMed: revision of the man-
uscript content, acquisition of data. Ursula G. Schulz, PhD: revision of
the manuscript content, acquisition of data. Wilhelm Ku ¨ker, FRCR: revi-
sion of the manuscript content, acquisition of data. Peter M. Rothwell,
PhD, FMedSci: study concept and design, draft and revision of the man-
uscript, analysis and interpretation of data, study supervision.
The authors report no disclosures relevant to the manuscript. Go to
Neurology.org for full disclosures.
Received December 1, 2011. Accepted in final form May 1, 2012.
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Practicing Neurologists: Take Advantage of These
CMS Incentive Programs
Medicare Electronic Health Records (EHR) Incentive Program
The Medicare EHR Incentive Program provides incentive payments to eligible professionals, eligi-
ble hospitals, and critical access hospitals as they adopt, implement, upgrade or demonstrate mean-
ingful use of certified EHR technology. Through successful reporting over a five-year period,
neurologists are eligible for up to $44,000 through the Medicare incentive program. To earn the
maximum incentive amount, eligible professionals must begin demonstrating meaningful use by
October 3, 2012. Learn more at www.aan.com/go/practice/pay/ehr.
Medicare Electronic Prescribing (eRx) Incentive Program
The Medicare eRx Incentive Program provides eligible professionals who are successful electronic
prescribers a 1% incentive for meeting reporting requirements during the 2012 calendar year. To be
eligible, physicians must have adopted a “qualified” eRx system in order to be able to report the eRx
measure. This program has also begun assessing payment adjustments for eligible professionals who
have not yet begun participation in the program. Learn more at www.aan.com/go/practice/pay/eRx.
Physician Quality Reporting System (PQRS)
The Physician Quality Reporting System provides an incentive payment for eligible professionals
who satisfactorily report data on quality measures for covered professional services furnished to
Medicare beneficiaries. Eligible professionals who report successfully in the 2012 PQRS Incen-
tive Program are eligible to receive a 0.5% bonus payment on their total estimated Medicare
Part B Physician Fee Schedule allowed charges for covered professional services. Learn more at
Neurology 79 September 18, 2012