From the Institute of Community Medicine (H.I., T.S.), University of
Tsukuba, Ibaraki-ken, Japan; the Department of Epidemiology and Mass
Examination (Y.N., S.S., A.K., M.I.), Osaka Medical Center for Cancer and
Cardiovascular Diseases, Osaka, Japan; the Department of Public Health (M.K.),
Ehime University School of Medicine, Ehime, Japan; the Division of
Epidemiology (D.R.J.), School of Public Health, University of Minnesota,
Minneapolis, Minn; and the Osaka Prefectural Institute of Public Health
(Y.K.), Osaka, Japan.
Correspondence to Hiroyasu Iso, MD, Institute of Community Medicine, University of Tsukuba, 1–1-1, Tennodai, Tsukuba-shi, Ibaraki-ken 305, Japan.
Methods—In rural northeastern Japan, people aged
Results—More than 80% of people aged 40 to 69 years were
screened in both communities in the 1960s. One community charged for
screening services after 1968, whereas the other community intensified
intervention; subsequently, screening rates and the follow-up of
hypertensive individuals declined in the minimal intervention
community, especially in men. In men, stroke incidence declined more
(P<0.001) in the full intervention (42% in the period
1970 to 1975, 53% in the period 1976 to 1981, and 75% in the period
1982 to 1987) than in the minimal intervention community (5% increase,
20% decrease, and 29% decrease, respectively); in women, the stroke
incidence declined about 45% to 65% in both communities. Changes in
stroke prevalence paralleled those in stroke incidence. Trends in
systolic blood pressure levels tend to explain the differential
stroke rates in men.
Conclusions—Delivery of hypertension control services through
intensive, free, community-wide screening and health education was
effective in prevention of stroke for men in a community.
Japan suffers higher mortality from stroke and lower mortality
from coronary heart disease than Western
countries.13 To ameliorate the epidemic of
stroke, community-based programs of hypertension control were launched
in Japan in the 1960s, including those we implemented in 1963 in 2
agricultural communities in northeastern Japan.14
Hypertension control efforts permeated both communities. However, the
municipal government in 1 of the communities started to charge the
participants for blood pressure screenings after 1968 and did not
replace the public health nurse when she retired in 1973, whereas the
government in the other community continuously supported the
community-based intervention program. This circumstance permitted the
observation of the long-term effect on blood pressure and its clinical
sequelae according to 2 levels of intensity of an intervention program.
Furthermore, the full intervention community conducted systematic
education classes for detected hypertensives, and used a home
broadcasting system for verbal health announcements via a speaker
attached to the telephone. No systematic classes or mass-media
education was conducted in the minimal intervention community.
We compared the 2 communities for participation in blood pressure
screenings and follow-up examinations and for trends in blood pressure
level and other stroke risk factors, stroke incidence, prognosis, and
prevalence between 1963 and 1987.
Blood Pressure Screenings and Surveys
Systolic and fifth-phase diastolic blood pressures
were measured by physician epidemiologists using a standard mercury
sphygmomanometer on the right arm after at least 5 minutes' seated
rest. The first measurement was used in data analysis.
Hypertension was defined as systolic blood pressure
Color photographs of the right ocular fundus were coded according to
Scheie's classification.15 Grades II or higher
hypertensive or arteriosclerotic changes were
regarded as a significant hypertensive change in the retinal
arterioles. Using the Minnesota Code16 in a
supine resting ECG, we regarded a high R wave (3–1) plus ST-T changes
(4–1 to 4–3 or 5–1 to 5–3) as hypertensive cardiac changes;
ischemic changes were rare.17 We
estimated the prevalence of atrial fibrillation
(8–3).18
We asked about history of diabetes mellitus, hypertension, stroke, and
coronary heart disease since 1963. Starting in 1975, we asked
about usual weekly alcohol intake (grams/d)19 and
smoking habits.
Stroke Incidence
We did not examine trends in stroke mortality or type of stroke,
because the population size was small, the accuracy of the death
certificate diagnosis was questionable before the introduction of CT in
the 1980s,22 and many stroke victims ultimately
die of other causes.23
1-Year Stroke Prognosis and Stroke Prevalence
Hypertension Control Program: Full Intervention Community
The network for the stroke prevention program included task forces,
which met twice yearly to discuss program implementation, 3 public
health nurses, 4 midwives, 28 community leaders, and about 180 of their
coworkers, ie, small district–leaders. The Osaka Medical Center
for Cancer and Cardiovascular Disease, the University
of Tsukuba, and the Akita Research Institute of Public Health helped
plan and organize the program and conducted the population surveys and
surveillance. Repeated systematic blood pressure screenings were free
of charge. High participation was a priority. Community- and small
district–leaders helped recruit residents aged
Between 1964 and 1967, about 100 to 150 hypertensive individuals
requiring medication were visited annually to confirm a referral,
provide health education, and enhance compliance. Hypertensives
requiring medication at the initial screening (n=519) were invited by 3
nurses and 4 midwives to 6 to 10 adult education classes annually from
1968 through 1970 and 4 adult classes annually in the later years.
Hypertensives not needing medication (n=806) were invited to 2 adult
classes annually. Newly detected hypertensives were also invited to
adult classes. Approximately 70% to 80% of the hypertensive
individuals attended adult classes. The rest were visited at home 1 to
2 times annually.
Treatment of hypertension was by local physicians, using primarily
thiazide diuretics and secondarily ß-adrenergic blocking
agents. Calcium channel antagonists and
angiotensin-converting enzyme inhibitors were
rarely used before the mid-1980s.
Classes dealt with blood pressure measurement and management and how to
reduce salt intake, including taste tests of low-salt soy bean soup and
pickles. Education focused on salt because average sodium intake in the
1960s was 20 g/d14 in a traditional Japanese
diet: a high intake of rice, salty soybean soup, and salt-preserved
pickles and fish, with low intake of meat, eggs, and dairy
foods.14 24 Reduction of excessive alcohol intake
such as 5 drinks or more per day was also emphasized. We recommended
that farmers rest adequately because farm work was extremely hard, but
did not emphasize weight control because most hypertensive individuals
were not obese in the 1960s.14
In 1967, about 150 volunteers for diet improvement were trained through
10 annual classes that enhanced knowledge of stroke and practical ways
of modifying diet and lifestyle. The volunteers offered health
education to about 1000 people per year at blood pressure screenings
and meetings at local public centers.
Municipal announcements were transmitted via a speaker attached to each
household telephone, originally intended for fire or earthquake
emergencies. Individuals could turn the speaker off. Announcements
recruited participants to blood pressure screenings and adult classes 1
week before and during the events and for a regular program on
cardiovascular health, aired for 3 minutes at 6:30
AM, 12:30 PM, and 6:30 PM
every Thursday. Rotating topics included reduction of salt intake, the
importance of balanced diet, and the importance of proper rest.
Hypertension Control Program: Minimal Intervention
Community
Data Analysis
Blood pressure levels were age-adjusted, and their population
differences were tested in each time period using ANCOVA. Linear trends
in 6-year stroke incidence per 1000 people and 1-year prognosis of
stroke were assessed using a
Seventy-seven percent of the initially screened hypertensive men
(n=266) in the full intervention community had 2 or more follow-up
screenings in 10 years compared with 59% of hypertensive men (n=112)
in the minimal intervention community; median numbers of follow-up
screenings were 4 and 2, respectively (P<0.01). The
respective percentages in 19 years were 82% and 65%; median numbers
of follow-up screenings were 5 and 4 (P<0.01). For women,
no community difference was evident: 79% of hypertensives (n=217) in
the full intervention community versus 75% of hypertensives (n=114) in
the minimal intervention community in 10 years and 84% versus 76% in
19 years; median number of participation was 4 versus 4 in 10 years and
6 versus 5 in 19 years.
Sex and age-adjusted 6-year stroke incidence rates among persons aged
No significant difference in 1-year prognosis was found between the
communities in the period 1964 to 1969. The proportion of fatal strokes
were 33% to 43% in the period 1964 to 1969 and subsequently declined
by half (P for trend <0.05) in both communities (except for
full intervention community men, who rebounded to baseline levels in
the period 1982 to 1987). No consistent trend was seen in the
proportions in the other prognosis categories. Sex and age-adjusted
prevalence of stroke among persons aged
The only source of information about blood pressure and hypertension
status is the blood pressure screenings, which may be biased by
differential response rates. Among men and women aged 40 to 69 years in
the 1960s, age-adjusted mean values of screening systolic and
diastolic blood pressures, prevalence of hypertension, and
hypertensive end-organ defects were almost identical between the 2
communities for both sexes (Table 4
For both men and women, the prevalence of atrial fibrillation and
diabetes mellitus ascertained at screening was
We interpret these findings as indicating that widespread screening,
referral, and follow-up for hypertension, supplemented by
community-based health education and broad citizen support (including
specific support roles for over 10% of the population over age 30),
were successful in reducing stroke rates for men in this Japanese rural
environment.
After 1968, when the municipal government minimized its support,
participation in blood pressure screenings and hypertensive follow-up
decreased in the minimal intervention community, especially in men.
Men's work schedules and generally low level of health-consciousness
may have contributed to reduced participation.24
On the other hand, participation by men in the full intervention
community may have been maintained both by the absence of charges and
by more frequent and flexibly scheduled blood pressure screenings. In
addition, the success of the intervention in men may be due partly to
initial high risk (average 149 mm Hg for systolic blood
pressure and 86 to 87 mm Hg for diastolic blood
pressure) and a high prevalence of hypertensive end-organ defects.
Why was the community difference in stroke occurrence minimal in women?
First, the initial blood pressure levels and stroke incidence were
lower in women than in men. Second, women were probably more health
conscious than men and were more available during the daytime. Decline
in participation in the minimal intervention community was not as great
among hypertensive women initially screened as it was among men. This
suggests that there were similar changes in health-related behaviors in
women between the 2 communities.
We hypothesized that systematic screening, referral, and follow-up
examinations, coupled with intensive health education and recognition
of personal risk in hypertensive individuals and the whole population,
are fundamental to community blood pressure control. In a community
heart disease prevention trial in the United States, systematic
screening encouraged health behavior changes resulting in lower blood
pressures and blood cholesterol
levels.25 If screening is the intermediary for
stroke reduction, blood pressure should change in proportion to the
intensity of screening and related activities. In support of this
hypothesis, in our study mean systolic blood pressures in men
declined more in the full intervention community than in the minimal
intervention community in the early 1970s and the early 1980s, although
no community difference was seen in the mid-1980s. This blood pressure
trend corresponded with the greater decline of stroke incidence and
prevalence in the full intervention community. The community difference
in mean systolic blood pressure was only seen in the early
1980s for women, when stroke prevalence declined in favor of the full
intervention community. Diastolic blood pressure, which
contributes less to the development of stroke than systolic
pressure,26 did not change between
communities.
We consider it likely that the reduced screening participation (by 16%
to 30% in men and 17% to 25% in women) and a consequent failure to
detect newly developed hypertensives in the minimal intervention
community contributed to a smaller reduction of stroke incidence there.
In the minimal intervention community, undetected hypertensive
individuals may have been less likely to participate in blood pressure
screenings, resulting in the observation of a consistently
smaller proportion of previously undetected hypertensives and a greater
proportion of treated and controlled hypertensives after the 1970s. Our
recent study27 in a different community supports
this viewpoint. There, 46% (2062/4496) of the population aged 40 to 69
years responded to a survey; 2 years later, we examined 87% (312/360)
of a random sample of nonparticipants. In nonparticipants, age-adjusted
systolic blood pressure levels were higher (11 mm Hg in
men and 4 mm Hg in women) and the prevalence of antihypertensive
medication use was lower (3% in men and 5% in women) than in
participants.27
A recent study indicated that treatment of hypertension had little
impact on the population risk of stroke, although high blood pressure,
current smoking, atrial fibrillation, and diabetes mellitus increased
risk of stroke.28 29 We examined trends in these
stroke risk factors as well as heavy
drinking,18 19 28 but found no community
difference in their trends. Although these risk factors may cause
stroke, they did not confound findings in this study.
Greater improvements in health behaviors and environmental factors,
such as reduction of sodium intake29 for men in
the full intervention community, may have contributed to the greater
reduction of stroke rates. In the full intervention community, average
dietary salt intake for men aged 40 to 59 years was 20 g/d in 1969 and
14 g/d in the period 1980 to 1983 according to a nutrition
study.14 The 1980s estimate of salt intake was
confirmed by 24-hour urine collection.30
Unfortunately, we have no comparable data on sodium intake in the
minimal intervention community. However, a community-based sodium
intervention in China demonstrated a larger reduction in sodium intake
and systolic blood pressure levels in the intervention
community than in the control community.31
The results of this study show this to be a good design to use to
evaluate community trials intended to reduce
cardiovascular diseases. First, the designated
communities were culturally similar at baseline, and both suffered from
the target disease (stroke). Blood pressure was sufficiently high in
both communities that small reductions were likely to have pronounced
effects on stroke. Second, penetration of this community-based program
was largely under local control and did not cross from the full
intervention community because of limited communication between
communities. At the time, hypertension control for stroke prevention
was seldom discussed nationally. In comparison, failure to demonstrate
differential intervention versus control community effects in
coronary heart disease risk reduction has been attributed to
rapid dissemination of principles via a pervasive health communication
network in Minnesota.12 32
Third, the intervention strategy was tailored to existing community and
cultural conditions, and thus the intervention itself may be
generalized in similar form to other communities of small population
size. Fourth, the evaluation of disease end points was unobtrusive,
highly specific and standardized, and independent of the intervention
dose.
An inherent weakness is that evaluation information about blood
pressure changes became biased when the intensity of intervention in
the minimal intervention community was scaled back. Therefore, we drew
cautious conclusions about the extent to which changes in stroke rate
were mediated by changes in blood pressure levels. In the situation of
intervention in these 2 communities, well-designed surveillance of
blood pressure was probably impossible because introduction of
systematic, community-wide blood pressure surveillance would have
reintroduced free screening in the minimal intervention community. It
is possible that reduced involvement in the minimal intervention
community might have resulted in a decline in the detection of stroke
cases during the 24 years. If so, the real difference in stroke
incidence between the 2 communities would be even greater than reported
here.
Other weaknesses are that the study was carried out in only 2
communities, and therefore the potential for chance results cannot be
dismissed, and that the design of the study was not preplanned and
lacked randomization. However, community-wide interventions are
difficult to preplan and carry out from a logistic perspective, and
this type of "weakness" may therefore be inherent in community
intervention research.33
In conclusion, a community-based hypertension control program augmented
the decline in stroke incidence and prevalence among men. We attribute
the success of this community program to active participation of
existing health resources in the detection and control of hypertension
and to consistently high participation in blood pressure
screenings, follow-up examinations, and community-wide health education
activities. A mix of public health screening, media-based messages and
education, and community involvement and activities is widely used in
the United States10 32 and
Finland7 11 to combat
cardiovascular disease. Enhancements in these methods
did not lead to accelerated disease reduction in
Minnesota,12 although acceleration in the decline
in ischemic heart disease mortality occurred in
Finland.34 The present study has public
health importance because it shows that a similar mix is effective in
stroke reduction in a rural Japanese setting.
Received December 4, 1997;
revision received May 13, 1998;
accepted May 13, 1998.
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© 1998 American Heart Association, Inc.
Original Contributions
Effects of a Long-term Hypertension Control Program on Stroke Incidence and Prevalence in a Rural Community in Northeastern Japan
Abstract
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
References
Background and Purpose—Although
randomized clinical trials have demonstrated the benefit of
antihypertensive treatment in preventing stroke, the effectiveness of
community-based programs is largely unknown. We investigated long-term
community-based prevention activities. 
30 years
numbered 3219 in the full intervention community and 1468 in the
minimal intervention community in 1965. Systematic blood pressure
screening and health education began in 1963. Stroke was
registered through 1987.
Key Words: community medicine • hypertension • intervention studies • stroke prevention
Introduction
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
References
Experimental
trials have demonstrated that treatment of hypertension prevents stroke
incidence and reduces stroke mortality in middle-aged and elderly
adults in both clinical and community
settings.1 2 3 4 5 6 Improvement in the detection,
referral, and treatment of hypertension has been demonstrated by
community trials compared with control
communities.7 8 9 10 However, none of these
community trials, primarily designed for prevention of coronary
heart disease, have demonstrated reduced stroke
rates.11 12
Subjects and Methods
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
References
Surveyed Population
The surveyed communities were Ikawa (full intervention) and a
district of city H (minimal intervention). These rural rice-farming
communities are 45 miles apart in Akita Prefecture, northeastern Japan.
Despite geographical closeness, the 2 communities have different local
governments and communicate little. In the full intervention community,
the censuses for ages 30 were 1509 men and 1710 women in 1965, and
1933 men and 2182 women in 1985. The populations aged 70 were 96 men
and 128 women in 1965, and 252 men and 359 women in 1985. The minimal
intervention community had about half as large a population as the full
intervention community and a similar age-sex
distribution (Table 1
). A previous investigation in both
communities showed only a 1% emigration in 10
years.14
View this table:
[in a new window]
Table 1. The Number of Subjects and the Number (Rates) of
Participation in Blood Pressure Screenings by Age and Sex in the Full
and Minimal Intervention Communities in the 1960s, the Early 1970s, the
Early 1980s, and the
Mid-1980s
Residents aged 30 in both communities were offered identical
blood pressure screenings. Initial screening was by physicians and
public health officials. Hypertensive individuals were rescreened
annually, while the rest of the community was rescreened every 4 years
in the full intervention community and every 2 years in the minimal
intervention community. 160
mm Hg and/or diastolic blood pressure 95 mm Hg
and/or current use of antihypertensive medication. Controlled
hypertensives were treated persons with systolic blood pressure
<160 mm Hg and diastolic blood pressure <95
mm Hg.
A surveillance team identified incident strokes in people aged
30, based on hospital reports, national insurance claims, local
physicians, ambulance records, death certificates, public health
nurses, and blood pressure surveys. In a household survey performed
between 1964 and 1966 we found no undetected
cases.14 In living cases we obtained a history,
made systematic neurological examinations, and reviewed medical
records of the local clinics and hospitals. Decedents' histories
were obtained from families, attending physicians, and/or medical
records. Final standardized diagnoses of stroke (a focal
neurological disorder with rapid onset that persisted for 24 hours or
more,20 21 excluding transient ischemic
attack) were made by a panel of 3 or 4 physician-epidemiologists, who
were blinded to risk factor status and the diagnoses of other
panelists, aware of the community of residence, but unaware of the
intention eventually to compare the 2 communities. The surveillance and
stroke diagnosis methods were identical across communities.
Stroke prognosis 1 year after onset was dead, dependent, or
independent with or without neurologic deficit (eg, hemiplegia or
dysarthria). Dependent stroke patients were those needing help with at
least 1 of the following: bathing, eating, dressing, toileting, or
walking. Stroke prevalence was defined as dependent or otherwise
neurologically deficient stroke.
Strategies for hypertension control24
included (1) systematic blood pressure screening for detection of
hypertensive individuals; (2) referral of high-risk individuals to
local clinics for antihypertensive medication to reduce high blood
pressure or treat end-organ effects in the retinal arterioles or ECG;
(3) health education for hypertensives at blood pressure screening
sites, adult classes, and nurse home visits; (4) training of about 150
"healthy diet" volunteers for health education; and (5)
community-wide media-disseminated education to encourage participation
in blood pressure screening and reduced salt intake. 30 using direct
contact and recruitment letters and helped arrange blood pressure
screenings at community centers and schools. To enhance participation,
blood pressure screening was added on Sundays beginning in 1971, and in
the evening beginning in 1977.
A similar organization was established in 1963 in the minimal
intervention community, including 1 public health nurse and 1 local
clinic. Strategies of the program were similar to those in the full
intervention community, but did not include adult classes or
community-wide media education. The municipal announcement system was
used only for recruiting participants to blood pressure screenings. The
initial blood pressure screening performed from 1964 through 1968 was
free of charge. However, the local government started to charge the
participants for blood pressure screening beginning in
1969.24 Between 1964 and 1972, the enthusiastic
nurse visited about 200 hypertensives each year. After her retirement
in 1973, the systematic visits ended. Three fourths of the referred
hypertensives attended a clinic outside the community.
To evaluate exposure to the intervention program, participation
rates at 4 blood pressure screenings between the 1960s and the 1980s
were compared between the 2 communities using the
2 test. Participation in follow-up
examinations of stroke-free hypertensive individuals detected at the
initial blood pressure screening was compared between communities by
the Wilcoxon rank sum test. 2 test for trend
for the periods 1964 to 1969, 1970 to 1975, 1976 to 1981, and 1982 to
1987 (Figure 1). Trends in stroke
prevalence were also assessed by a 2 test for
trend in 1972, 1977, 1982, and 1987 (Figure 2). Community differences in stroke
incidence and prevalence in each time period were examined by
2 test. Direct age-adjustment of rates and
proportions was calculated using 10-year categories of the 1960s'
pooled populations.
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Figure 1. Sex-specific, age-adjusted stroke incidence
in the full intervention community (closed circle) and the minimal
intervention community (open circle), men and women aged 30 years.
Difference from the minimal intervention community:
P<0.01, 
P<0.001.
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Figure 2. Sex-specific, age-adjusted stroke prevalence in
the full intervention community (closed circle) and the minimal
intervention community (open circle), men and women aged 30 years.
Difference from the minimal intervention community:
P<0.01, P<0.001.
Results
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
References
The age-adjusted participation rate in both communities in the
1960s blood pressure screening was approximately 70% to 80% for men
and 80% to 90% for women (Table 1
). Between the 1960s and the
mid-1980s, the age-adjusted participation rates remained high in the
full intervention community, but declined in the minimal intervention
community to about 50% in men and 60% in women after the mid-1970s,
particularly in ages 30 to 39 and ages 70. The following
analyses of blood pressure were restricted to men and women
aged 40 to 69 years, groups whose baseline participation rates were
high. 30 did not differ between the 2 communities in the period 1964 to
1969 (Table 2, Figure 1). Stroke
incidence declined in men in subsequent periods (test for trend
within each community: P<0.001) and was significantly
greater in the full intervention than in the minimal intervention
community: 42% decrease versus 5% increase in the period 1970 to 1975
(P<0.01), 53 versus 19% decrease in the period 1976 to
1981 (P<0.05) and 75 versus 29% decrease in the period
1982 to 1987 (P<0.001). For women, there was no difference
in stroke incidence in the 3 later periods.
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Table 2. Age-Adjusted Stroke Incidence Per 1000 in the Full
and Minimal Intervention Communities in the Periods 1964–69, 1970–75,
1976–81, and 1982–87 30 did not differ between the
2 communities in 1972 (Table 3, Figure 2). For men, stroke prevalence declined
in the full intervention community in subsequent periods (test for
trend: P<0.001), while the prevalence did not change
significantly in the minimal intervention community. For women, stroke
prevalence declined in both communities (P<0.001);
prevalence was reduced in full intervention compared with the minimal
intervention community only in 1982.
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Table 3. Age-Adjusted Stroke Prevalence Per 1000 in the Full
and Minimal Intervention Communities in 1972, 1977, 1982, and
1987 ). The
proportion of hypertensive individuals who were treated was only 17%
to 25% for men and women in the 2 communities. As a result of
screening, approximately 80% of the detected hypertensives were
referred to local physicians for treatment in both communities. For
men, the full intervention community showed a 3 to 4 mm Hg lower
mean systolic blood pressure than the minimal intervention
community in the early 1970s and the early 1980s but not in the
mid-1980s. A community difference in systolic blood pressure
for women was found in the early 1980s but not in the other periods.
The prevalence of hypertensive end-organ defects was lower in the full
intervention community than in the minimal intervention community for
men and women in the early 1970s and for women in the mid-1980s. The
proportion of hypertensives was consistently smaller in the
full intervention community than in the minimal intervention community
after the early 1970s for both sexes. Contrary to expectations, among
hypertensives the proportion previously undetected was
consistently greater and the proportion treated and controlled
was lower in the full intervention community than in the minimal
intervention community.
View this table:
[in a new window]
Table 4. Age-Adjusted Means and Standard Errors of Systolic
and Diastolic Blood Pressures and Proportions of Hypertension
Detection, Treatment, and Control Status and Prevalence of Other Risk
Status in Men and Women Aged 40–69 Who Participated in the Blood
Pressure Screenings 
2% in both
communities in the 1960s. The prevalence of atrial fibrillation did not
change over time in either community. The prevalence of diabetes
mellitus increased over time similarly in both communities. The
proportions of current smokers and heavy drinkers did not change in the
latest 2 time periods for either community, although these behaviors
were less frequently reported in the minimal intervention community
than in the full intervention community.
Discussion
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
References
The present study showed a larger decline in stroke incidence
and prevalence in men aged 30 in a rural Japanese community that
between the 1960s and the mid-1980s received a full range of
community-wide hypertension interventions than that seen in a
demographically similar community that received minimal intervention
after 1968. The overall decline in incidence for men was 75% in the
full intervention community and 29% in the minimal intervention
community. Stroke occurrence in women was less affected, although the
prevalence of stroke was differential between the 2 communities in
1982. The incidence of coronary heart disease, which has been
reported elsewhere,14 24 was less than 10% of
the stroke incidence in the 1960s and did not change over time in
either community.
Acknowledgments
The authors thank Prof Aaron R. Folsom, University of Minnesota,
for valuable comments on the manuscript. This study was supported in
part by the Ministry of Health and Welfare, Tokyo, Japan
(Research on Cardiovascular Diseases 4C-2,
1992–94).
References
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
References
1.
Veterans Administration Cooperative Study Group on
Antihypertensive Agents. Effects of treatment on morbidity in
hypertension: results in patients with diastolic blood
pressures averaging 115 through 129 mmHg. JAMA. 1967;202:1028–1034.
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