Proportions of Stroke Subtypes Among Men and
Women >40 Years of Age in an Urban Japanese City in
1992, 1997, and 2002
Akihiko Kitamura, MD; Yuko Nakagawa, MD; Minoru Sato, MD; Hiroyasu Iso, MD;
Shinichi Sato, MD; Hironori Imano, MD; Masahiko Kiyama, MD; Takeo Okada, MD;
Hiroshi Okada, MD; Minoru Iida, MD; Takashi Shimamoto, MD
Downloaded from http://stroke.ahajournals.org/ by guest on June 18, 2017
Background and Purpose—Higher proportions of hemorrhagic stroke and lacunar infarction were reported in rural Japan
compared with those in Western countries. We examined the relative proportions of stroke subtypes in an urban
Japanese city where westernized lifestyles are more common than in rural areas.
Methods—Stroke registration was performed in 1992, 1997, and 2002 for residents ⱖ40 years of age who were admitted
with acute strokes to all of the 10 hospitals with ⱖ90 beds in Yao City, Osaka, Japan. Strokes were classified as
intraparenchymal hemorrhage, subarachnoid hemorrhage, or ischemic strokes (embolic infarction, large-artery occlusive
infarction, lacunar infarction, and unclassified thrombotic infarction) by criteria using computed tomography or MRI.
Results—A total of 650 first-ever strokes were registered. The age-adjusted proportion of each stroke subtype was not
significantly different among the 3 study periods in both men and women. Throughout the 3 periods, intraparenchymal
hemorrhage, subarachnoid hemorrhage, and ischemic stroke accounted for 26%, 7%, and 65% in men, respectively. In
women, the respective proportions were 29%, 21%, and 44%. The proportion of each subtype for total ischemic strokes
was as follows: 51% to 61% lacunar infarction, 25% to 26% large-artery occlusive infarction, and 11% to 17% embolic
infarction.
Conclusions—Our study showed that hemorrhagic stroke represented a large proportion of all strokes, especially among
women, and lacunar infarction was the most common subtype of ischemic stroke among both men and women in Yao
City, which differed from findings in Western countries. (Stroke. 2006;37:1374-1378.)
Key Words: brain infarction 䡲 epidemiology 䡲 intracranial hemorrhages 䡲 stroke classification
A
ccording to population-based studies on stroke incidence conducted in the 1960s and 1970s, Japanese rural
populations had a higher incidence of total stroke, in particular intraparenchymal hemorrhage, compared with those in
the United States and European countries.1– 4 The higher
proportions of intraparenchymal hemorrhage and lacunar
infarction in rural Japan than in US populations have been
confirmed by epidemiological studies using computed tomography (CT) as a diagnostic tool since the 1970s.5–10
However, there have been few findings about the relative
proportions of stroke subtypes in the Japanese urban population, where westernized lifestyles are more common than in
rural areas. This study describes the proportions of stroke
subtypes as estimated by data from hospital-based stroke
registry in an urban Japanese city.
men and 140 821 women) in the calendar year 2000. Persons living
in areas outside Yao City were not registered. Stroke registration was
performed in 1992, 1997, and 2002 for residents aged ⱖ40 years
who were admitted with acute strokes to all of the 10 hospitals with
ⱖ90 beds in Yao City. Patients with an acute neurological illness
were usually admitted to these hospitals, which provide diagnoses
and acute care. The total number of beds of the participating 10
hospitals was 2149, which occupied 90% of the total 2391 beds of all
14 hospitals in the city in 1992. Among the 10 hospitals, 2 were
closed between 1993 and 1996; therefore, 8 hospitals participated in
1997 and 2002. According to the official statistics about ambulance
use, the proportion of residents who were transferred to neurosurgery
departments in the participating hospitals among those in all hospitals, including those outside Yao City, was 92% (920 of 995) in
1992, 89% (1311 of 1476) in 1997, and 89% (1545 of 1740) in 2002.
The proportion of persons aged ⱖ70 years among the subjects
increased from 10% in 1992 to 17% in 2002 for men and from 17%
in 1992 to 23% in 2002 for women.
All hospitalized residents who experienced a first stroke were
registered. The hospital records for all patients with admission
records of possible stroke or discharge diagnoses of stroke were
reviewed by the study physicians (A.K. and Y.N.). Once a case
Subjects and Methods
The surveyed population were residents of Yao City, an urban city in
Osaka Prefecture in Japan, with a total census of 274 777 (133 956
Received January 31, 2006; final revision received March 28, 2006; accepted March 29, 2006.
From the Osaka Medical Center for Health Science and Promotion (A.K., S.S., H. Imano, M.K., T.O., M.I., T.S.), Japan; Neyagawa Public Health
Center (Y.N.), Japan; Yao Medical Association (M.S., H.O.), Japan; and Department of Public Health Medicine (H. Iso), University of Osaka, Japan.
Correspondence to Dr Akihiko Kitamura, Osaka Medical Center for Health Science and Promotion, 1-3-2 Nakamichi, Higashinari-ku, Osaka 537-0025,
Japan. E-mail [email protected]
© 2006 American Heart Association, Inc.
Stroke is available at http://www.strokeaha.org
DOI: 10.1161/01.STR.0000221714.96986.5f
1374
Kitamura et al
TABLE 1.
Stroke Subtypes in an Urban Japanese City
No. of First-Ever Stroke Patients in 1992, 1997, and 2002, Yao, Japan
1992
Men
Women
1997
Proportion, %
n
2002
Age
n
40–49
4
4
5
4
7
5
50–59
20
21
22
19
31
21
60–69
30
32
51
45
46
32
70–79
28
30
22
19
38
26
ⱖ80
13
14
14
12
23
16
Proportion, %
n
Proportion, %
100
Total
95
100
114
100
145
40–49
4
4
5
5
0
0
50–59
11
12
10
11
16
15
60–69
19
20
25
27
29
27
70–79
32
34
22
24
28
26
ⱖ80
29
31
30
33
36
33
Total
95
100
92
100
109
100
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was identified, we obtained information about neurological symptoms, medical history, and findings of several diagnostic tests, including CT, MRI, cerebral angiography, electrocardiography, and
echocardiography.
The diagnosis of stroke was made according to the criteria of the
National Survey of Stroke,11 which requires a constellation of
neurological deficits of sudden or rapid onset lasting ⱖ24 hours or
until death. We excluded stroke resulting from infection, trauma,
malignancy, and vascular malformation. In addition, recurrent
strokes and patients with asymptomatic lesions detected by brain
imaging were excluded. Events were classified as intraparenchymal
hemorrhage, subarachnoid hemorrhage, or ischemic strokes by CT or
MRI using standardized criteria.12 A stroke case that was diagnosed
clinically but showed no lesion on CT or MRI was classified as
stroke of undetermined type. Ischemic stroke was categorized as
embolic infarction or thrombotic infarction. A diagnosis of embolic
infarction was made when evidence of an embolic source was
present in the medical records and if imaging studies and a neurology
consultation supported the diagnosis. Thrombotic infarctions were
further classified as large-artery occlusive infarction, lacunar infarction, or unclassified thrombotic infarction based on the results of CT
or MRI, according to the criteria of the Perth Community Stroke Study.13
TABLE 2.
1375
We calculated age-adjusted proportions of stroke subtypes by the
direct method of standardization to the age distribution of the total
stroke patients to compare the proportions in 3 study periods as
well as between men and women. Sex-specific proportions of stroke
subtypes were examined because proportions of stroke subtypes
were reported to vary between the sexes.5,7 Linear trends in the
proportions in 1992, 1997, and 2002 were tested using the ␹2 test for
trend. The study was approved in advance by the ethics committee of
the Osaka Medical Center for Health Science and Promotion.
Results
A total of 650 first-ever strokes were recorded: 190 in 1992, 206
in 1997, and 254 in 2002. The highest proportion of patients
comprised men 60 to 69 years of age and women 70 to 79 years
of age or ⱖ80 years of age in each study period (Table 1).
The numbers and age-adjusted proportions of stroke subtypes among total strokes are shown in Table 2. The proportion of each stroke subtype did not significantly differ among
the 3 study periods in either sex. Throughout the 3 periods,
Age-Adjusted Proportions of Stroke Subtypes Among Total Strokes in 1992, 1997, and 2002, Yao, Japan
1992
1997
2002
Total
Proportion, %
n
Proportion, %
n
Proportion, %
P for
Trend
36
28 (20–37)
35
23 (16–30)
96
26 (21–30)
0.56
4
3 (0–6)
16
10 (5–15)
26
7 (4–9)
0.07
63 (54–73)
72
67 (58–76)
92
65 (57–73)
223
65 (60–70)
0.87
5 (0–9)
2
2 (0–4)
2
1 (0–3)
2 (1–4)
䡠䡠䡠
n
Proportion, %
n
25
26 (17–35)
6
5 (1–10)
59
5
Men
Hemorrhagic stroke
Intraparenchymal hemorrhage
Subarachnoid hemorrhage
Ischemic stroke
Stroke of undetermined type
Total
95
100
114
100
145
100
9
354
100
Women
Hemorrhagic stroke
Intraparenchymal hemorrhage
Subarachnoid hemorrhage
27
28 (19–37)
24
27 (18–36)
37
31 (23–40)
88
29 (24–34)
0.54
12
14 (7–21)
26
30 (20–39)
18
18 (11–25)
56
21 (16–26)
0.71
Ischemic stroke
45
45 (35–55)
38
40 (30–50)
51
45 (35–54)
134
44 (38–50)
0.99
Stroke of undetermined type
11
13 (6–19)
4
4 (0–8)
3
2 (0–5)
18
6 (3–8)
䡠䡠䡠
Total
95
Numbers in parentheses are 95% CIs.
100
92
100
109
100
296
100
1376
Stroke
June 2006
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intraparenchymal hemorrhage, subarachnoid hemorrhage,
and ischemic stroke accounted for 26%, 7%, and 65% of all
strokes among men. For women, intraparenchymal hemorrhage and subarachnoid hemorrhage accounted for 29% and
21%, respectively, of all strokes, resulting in higher proportions of hemorrhagic stroke than ischemic stroke (50% versus
44%). The proportions of intraparenchymal hemorrhage,
subarachnoid hemorrhage, and ischemic stroke were 31%,
10%, and 56%, respectively, among men 40 to 69 years of
age, and 20%, 4%, and 73% among those ⱖ70 years of age.
For women, the respective proportions were 29%, 27%, and
39% among those 40 to 69 years of age, and 31%, 14%, and
50% among those ⱖ70 years of age.
The age-adjusted proportions of stroke subtypes among
ischemic strokes did not significantly differ among the 3
study periods in either sex (Table 3). Throughout the 3
periods, lacunar infarction, large-artery occlusive infarction,
and embolic infarction accounted for 51%, 25%, and 17% of
all ischemic strokes among men and 61%, 26%, and 11%
among women. The proportions of lacunar infarction, largeartery occlusive infarction, and embolic infarction were 55%,
29%, and 12%, respectively, among men 40 to 69 years of
age, and 48%, 22%, and 22% among those ⱖ70 years of age.
For women, the respective proportions were 70%, 24%, and
4% among those 40 to 69 years of age, and 51%, 27%, and
19% among those ⱖ70 years of age.
Discussion
We observed a relatively high proportion of hemorrhagic
stroke in Yao City between 1992 and 2002. Intraparenchymal
hemorrhage accounted for ⬇30% of all strokes in men and
women. Furthermore, in women, subarachnoid hemorrhage
constituted ⬇20% of all strokes, and therefore about half of
the strokes were hemorrhagic type in women. These proportions of stroke subtypes were similar to those from our
previous study6 using the same criteria in rural Japan.
TABLE 3.
Findings from other community-based studies on firstever stroke subtypes are shown in Table 4. Compared with
the results from 3 hospital-based studies in the United
States,8 –10 the present study showed the higher proportions
of both intraparenchymal hemorrhage and subarachnoid
hemorrhage, which were similar to previous hospital-based
studies in rural Japan5 as well as in Korea,14 although there
may be differences in age distribution and criteria of
diagnosis among the studies.
Reviewing population-based studies since the 1990s worldwide, we found that the proportion of intraparenchymal
hemorrhage was reported to be highest in Chinese,22 followed
by the proportions in rural Japanese7 and Chileans.21 The
proportion of subarachnoid hemorrhage was highest in
Finns,19 followed by the proportion in Japanese.7 The high
proportion of hemorrhagic stroke in Japanese similar to other
Asian populations may be attributed to environmental factors
as well as genetic factors. The national survey of circulatory
disorders with a representative sample of Japanese ⱖ30 years of
age in 200023 showed that hypertension and heavy drinking,
strong risk factors for hemorrhagic stroke, were common in
Japan. The proportion of hypertension, defined as systolic
pressure of ⱖ140 mm Hg, diastolic pressure of ⱖ90 mm Hg, or
taking antihypertensive medication, was reported 57% in men
and 45% in women. The proportion of heavy drinkers, defined
as persons having ⬎14 drinks per week, was 46% in men and
11% in women. The proportions of hypertension and heavy
drinkers among Japanese seem to be higher than those among
Americans,24 although full comparisons cannot be made.
The proportion of ischemic stroke was higher among men
and women ⱖ70 years of age than among those 40 to 69 years
of age. The higher proportion of ischemic stroke among older
persons was reported from other studies.5,15–17,21 With regard
to the subclassification of ischemic stroke, lacunar infarction
accounted for ⬎50% of all ischemic strokes in the present
study, which was similar to previous studies in Japanese rural
Age-Adjusted Proportions of Stroke Subtypes Among Ischemic Strokes in 1992, 1997, and 2002, Yao, Japan
1992
n
Proportion, %
1997
n
Proportion, %
2002
n
Total
Proportion, %
n
Proportion, %
P for
Trend
Men
Thrombotic infarction
Lacunar infarction
32
50 (38–63)
37
49 (38–61)
46
50 (40–61)
115
51 (45–58)
0.92
Large-artery occlusive infarction
14
24 (13–35)
19
26 (16–36)
24
26 (17–35)
57
25 (20–31)
0.74
Unclassified thrombotic infarction
5
10 (2–17)
5
7 (1–13)
4
4 (0–9)
14
7 (3–10)
8
16 (6–25)
11
18 (9–27)
18
19 (11–27)
37
17 (12–22)
䡠䡠䡠
0.51
Embolic infarction
Total
59
100
72
100
92
100
223
100
Women
Thrombotic infarction
Lacunar infarction
26
58 (44–73)
19
53 (37–69)
32
62 (48–75)
77
61 (53–69)
0.60
Large-artery occlusive infarction
10
24 (12–36)
15
38 (22–53)
10
19 (8–29)
35
26 (19–33)
0.41
Unclassified thrombotic infarction
2
5 (0–12)
0
0
1
1 (0–4)
3
2 (0–4)
7
12 (3–22)
4
5 (0–12)
8
15 (5–24)
19
11 (6–17)
䡠䡠䡠
0.92
Embolic infarction
Total
Numbers in parentheses are 95% CIs.
45
100
38
100
51
100
134
100
Kitamura et al
TABLE 4.
Stroke Subtypes in an Urban Japanese City
1377
Distribution of First-Ever Stroke Subtypes by Sex in Community-Based Studies
Proportion, %
Study
Study Period
Age
Sex
Total No.
of Cases
Intraparenchymal
Hemorrhage
Subarachnoid
Hemorrhage
Ischemic
Stroke
Other
Type
Hospital-based studies
Harvard, United States8
1978
All
Men and women
649
10
6
84
0
South Alabama, United States9
1980
All
Men and women
160
8
6
85
0
Stroke Data Bank, United States
1983–1986
All
Men and women
1805
13
13
70
3
Korea14
1989–1990
All
Men and women
3201
31
18
48
1
Akita Prefecture, rural Japan5
1983–1985
All
Men
1287
30
9
61
0
Women
881
31
21
48
0
10
Yao, urban Japan (the present study)
1992, 1997, 2002
ⱖ40
Men
354
27
7
63
3
Women
296
30
19
45
6
Men
203
20
3
68
9
Population-based studies
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Belluno, Italy15
1992–1993
All
L’Aquila, Italy16
1994–1998
All
ESPro, Germany17
1994–1996
All
Arcadia, Greece18
1993–1995
ⱖ18
Finland19
2002
Melbourne, Australia20
1996–1997
35–74
All
Iquique, Chile21
2000–2002
All
Beijing, China22
1991–2000
All
Women
271
20
2
66
12
Men
398
15
3
80
2
Women
421
15
3
80
2
Men
145
12
3
81
3
Women
209
14
4
77
5
Men
309
16
2
81
1
Women
246
11
3
80
6
Men
6705
16
9
75
0
Women
4185
15
17
68
0
Men
126
17
2
75
5
Women
150
12
6
70
12
Men
164
26
5
63
6
Women
128
20
5
64
10
Men
䡠䡠䡠
30
1
66
3
䡠䡠䡠
26
1
69
4
䡠䡠䡠
37
1
54
8
Women
Shanghai, China22
Changsha, China22
1991–2000
1991–2000
All
All
Men
Women
䡠䡠䡠
34
2
53
11
Men
䡠䡠䡠
54
1
41
5
2
42
6
Men
䡠䡠䡠
86
49
23
7
70
0
Women
111
19
12
69
0
Women
Hisayama, rural Japan7
1988–2000
ⱖ40
populations.6,25 The proportion of lacunar infarction in Japanese communities (51% to 61%) was much greater than that
in the previous 3 American hospital-based studies (15% to
27%)8 –10 and an Australian community-based study (10%).13
According to a recent nationwide hospital-based study of
Japanese,26 the proportions of lacunar stroke, atherothrombotic infarction, and cardioembolic infarction were 39%,
33%, and 22%, respectively, but these findings were based on
156 large hospitals all over Japan, of which ⬎50% equipped
a specialized stroke care unit or intensive care unit. Therefore, in that study, it is possible that severe ischemic patients
with cardioembolic or atherothrombotic stroke were likely to
be admitted to the participating hospitals.
As for the study limitations, severe ischemic stroke cases
can be transported to other stroke centers with dedicated
stroke teams outside Yao City. However, according to the
statistics of ambulance records, only ⬇10% of the total
ambulance patients were transported to hospitals outside Yao
City. Furthermore, this proportion did not change in 3 survey
periods. Thus, the transportation of patients out of the city is
unlikely to affect the results substantially. Second, it is
uncertain whether the present findings in Yao City were
generalized to larger cities in Japan.
In conclusion, our study showed that hemorrhagic stroke
represented a large proportion of all strokes, especially
among women, and lacunar infarction was the most common
subtype of ischemic stroke among both men and women in
Yao City, which differed from findings in Western countries.
We found no significant change in proportions of stroke
subtypes during the last decade in this population. The
present findings imply the importance of enhancing health
care services to reduce case fatality among hemorrhagic
stroke patients and to prevent stroke in Japan.
1378
Stroke
June 2006
Appendix
The participating hospitals and the directors are listed in order of the
number of eligible patients entered in the study. Ishinkai Yao Sougou
Hospital: T. Mori, MD. Yao Tokusyukai Sougou Hospital: M.
Fukuda, MD. Kouseikai Daiichi Hospital: T. Onishi, MD. Kijima
Cyuo Hospital: N. Kijima, MD. Imagawa Hospital: T. Inoyama, MD.
Yao Municipal Hospital: S.Yoneda, MD. Kijima Hospital Honin: H.
Kijima, MD. Toho Yao Hospital: T. Umada, MD. Yao Eiwakai
Hospital: K. Ozaki, MD. Meiwa Kinen Hospital: T. Katou, MD.
References
Downloaded from http://stroke.ahajournals.org/ by guest on June 18, 2017
1. Aho K, Harmsen P, Hatano S, Marquardsen J, Smirnov VE, Strasser T.
Cerebrovascular disease in the community: results of a WHO collaborative study. Bull World Health Organ. 1980;58:113–130.
2. Tanaka H, Ueda Y, Date C, Baba T, Yamashita H, Hayashi M, Shoji H,
Owada K, Baba KI, Shibuya M, Kon T, Detels R. Incidence of stroke in
Shibata, Japan: 1976 –1978. Stroke. 1981;12:460 – 466.
3. Komachi Y, Tanaka H, Shimamoto T, Handa K, Iida M, Isomura K,
Kojima S, Matsuzaki T, Ozawa H, Takahashi H, Tsunetoshi Y. A collaborative study of stroke incidence in Japan: 1975–1979. Stroke. 1984;
15:28 –36.
4. Ueda K, Hasuo Y, Kiyohara Y, Wada J, Kawano H, Kato I, Fujii I, Yanai
T, Omae T, Fujishima M. Intracerebral hemorrhage in a Japanese community, Hisayama: incidence, changing pattern during long-term
follow-up, and related factors. Stroke. 1988;19:48 –52.
5. Suzuki K, Kutsuzawa T, Takita K, Ito M, Sakamoto T, Hirayama A, Ito
T, Ishida T, Ooishi H, Kawakami K, Hirota K, Ogasawara T, Yoshida J,
Tamura T, Hattori S, Iwabuchi S, Karouji Y, Waga T, Oosato Y, Yazaki
K, Saito T, Oouchi T, Kojima S. Clinico-epidemiologic study of stroke in
Akita, Japan. Stroke. 1987;18:402– 406.
6. Sankai T, Miyagaki T, Iso H, Shimamoto T, Iida M, Tanigaki M, Naito
Y, Sato S, Kiyama M, Kitamura A, Konishi M, Terao A, Doi M, Komachi
Y. A population-based study of the proportion by type of stroke
determined by computed tomography scan (in Japanese with English
abstract). Nippon Koshu Eisei Zasshi. 1991;38:901–909.
7. Kubo M, Kiyohara Y, Kato I, Tanizaki Y, Arima H, Tanaka K, Nakamura
H, Okubo K, Iida M. Trends in the incidence, mortality, and survival rate
of cardiovascular disease in a Japanese community: the Hisayama study.
Stroke. 2003;34:2349 –2354.
8. Mohr JP, Caplan LR, Melski JW, Goldstein RJ, Duncan GW, Kistler JP,
Pessin MS, Bleich HL. The Harvard Cooperative Stroke Registry: a
prospective registry. Neurology. 1978;28:754 –762.
9. Gross CR, Kase CS, Mohr JP, Cunningham SC, Baker WE. Stroke in
south Alabama: incidence and diagnostic features–a population based
study. Stroke. 1984;15:249 –255.
10. Foulkes MA, Wolf PA, Price TR, Mohr JP, Hier DB. The Stroke Data
Bank: design, methods, and baseline characteristics. Stroke. 1988;19:
547–554.
11. Walker AE, Robins M, Weinfeld FD. The National Survey of Stroke.
Clinical findings. Stroke. 1981;12(suppl 1):I13–I44.
12. Iso H, Rexrode K, Hennekens CH, Manson JE. Application of computer
tomography-oriented criteria for stroke subtype classification in a prospective study. Ann Epidemiol. 2000;10:81– 87.
13. Anderson CS, Jamrozik KD, Burvill PW, Chakera TM, Johnson GA,
Stewart-Wynne EG. Determining the incidence of different subtypes of
stroke: results from the Perth Community Stroke Study, 1989 –1990. Med
J Aust. 1993;158:85– 89.
14. Korean Neurological Association. Epidemiology of cerebrovascular
disease in Korea—a collaborative study, 1989 –1990. J Korean Med Sci.
1993;8:281–289.
15. Lauria G, Gentile M, Fassetta G, Casetta I, Agnoli F, Andreotta G,
Barp C, Caneve G, Cavallaro A, Cielo R, Mongillo D, Mosca M,
Olivieri P. Incidence and prognosis of stroke in the Belluno province,
Italy. First-year results of a community-based study. Stroke. 1995;26:
1787–1793.
16. Carolei A, Marini C, Di Napoli M, Di Gianfilippo G, Santalucia P,
Baldassarre M, De Matteis G, di Orio F. High stroke incidence in the
prospective community-based L’Aquila registry (1994 –1998). First
year’s results. Stroke. 1997;28:2500 –2506.
17. Kolominsky-Rabas PL, Sarti C, Heuschmann PU, Graf C, Siemonsen S,
Neundoerfer B, Katalinic A, Lang E, Gassmann KG, von Stockert TR. A
prospective community-based study of stroke in Germany–the Erlangen
Stroke Project (ESPro): incidence and case fatality at 1, 3, and 12 months.
Stroke. 1998;29:2501–2506.
18. Vemmos KN, Bots ML, Tsibouris PK, Zis VP, Grobbee DE, Stranjalis
GS, Stamatelopoulos S. Stroke incidence and case fatality in southern
Greece: the Arcadia stroke registry. Stroke. 1999;30:363–370.
19. Pajunen P, Paakkonen R, Hamalainen H, Keskimaki I, Laatikainen T,
Niemi M, Rintanen H, Salomaa V. Trends in fatal and nonfatal strokes
among persons aged 35 to ⱖ85 years during 1991–2002 in Finland.
Stroke. 2005;36:244 –248.
20. Thrift AG, Dewey HM, Macdonell RA, McNeil JJ, Donnan GA.
Incidence of the major stroke subtypes: initial findings from the North
East Melbourne stroke incidence study (NEMESIS). Stroke. 2001;32:
1732–1738.
21. Lavados PM, Sacks C, Prina L, Escobar A, Tossi C, Araya F, Feuerhake
W, Galvez M, Salinas R, Alvarez G. Incidence, 30-day case-fatality rate,
and prognosis of stroke in Iquique, Chile: a 2-year community-based
prospective study (PISCIS project). Lancet. 2005;365:2206 –2215.
22. Jiang B, Wang WZ, Chen H, Hong Z, Yang QD, Wu SP, Du XL, Bao
QJ. Incidence and trends of stroke and its subtypes in China: results from
three large cities. Stroke. 2006;37:63– 68.
23. The Ministry of Health, Labour and Welfare. A Report of The Fifth
National Survey of Cardiovascular Diseases (in Japanese). Tokyo, Japan:
Chuohoki Syuppan; 2003:45–190.
24. National Center for Health Statistics. Health, United States, 2004 With
Chartbook on Trends in the Health of Americans. Hyattsville, Md:
National Center for Health Statistics; 2004:213–244.
25. Tanizaki Y, Kiyohara Y, Kato I, Iwamoto H, Nakayama K, Shinohara N,
Arima H, Tanaka K, Ibayashi S, Fujishima M. Incidence and risk factors
for subtypes of cerebral infarction in a general population: the Hisayama
study. Stroke. 2000;31:2616 –2622.
26. Kimura K, Kazui S, Minematsu K, Yamaguchi T. Japan Multicenter
Stroke Investigator’s Collaboration. Analysis of 16 922 patients with
acute ischemic stroke and transient ischemic attack in Japan. A
hospital-based prospective registration study. Cerebrovasc Dis. 2004;18:
47–56.
Proportions of Stroke Subtypes Among Men and Women ≥40 Years of Age in an Urban
Japanese City in 1992, 1997, and 2002
Akihiko Kitamura, Yuko Nakagawa, Minoru Sato, Hiroyasu Iso, Shinichi Sato, Hironori Imano,
Masahiko Kiyama, Takeo Okada, Hiroshi Okada, Minoru Iida and Takashi Shimamoto
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Stroke. 2006;37:1374-1378; originally published online May 11, 2006;
doi: 10.1161/01.STR.0000221714.96986.5f
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