(63) VETERANS ADMINISTRATION COOPERATIVE STUDY GROUP ON
ANTIHYPERTENSIVE AGENTS. Effects of treatment on morbidity in
hypertension. II. Results in patients with diastolic blood pressure averaging
90 through 114 mm Hg. Journal of the American Medical Association 213(7):
1143-1152, August 17, 1970.

(64) WERKO, L. Prevention of heart attacks. A multifactorial preventive trial in
Gothenburg, Sweden. Annals of Clinical Research 11(2): 71-79, April 1979.

(65) WILHELMSEN, L. Risk factors for disease according to population studies in
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September 23-25, 1980. In: Bostrom, H., Ljungstedt, H. (Editors), Medical
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(66) WILHELMSEN, L., TIBBLIN ,G., WERKO, L. A primary preventive study in
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(67) WOLFF, F.W., LIN DEMAN, R.D. Effects of treatment in hypertension.
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(68) WORLD HEALTH ORGANIZATION EUROPEAN COLLABORATIVE
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(70) WORLD HEALTH ORGAN IZATION EXPERT COMMITTEE. Prevention of

326
APPENDIX A: TRENDS IN
CARDIOVASCULAR
DISEASES

327
Introduction and Overview
Mortality Trends

The cardiovascular diseases—primarily heart, cerebrovascular,
hypertensive, and peripheral vascular diseases—are widely preva-
lent in our society and cause substantial illness and death. With the
increasing control of infectious and parasitic diseases, especially
during the first half of the 20th century, life expectancy has
improved and the major cardiovascular diseases as a group have
become the underlying cause of approximately 50 percent of all
deaths in the United States. They are responsible for more than
950,000 deaths each year (Table 1) (16, 27). The economic cost of
heart disease alone was estimated in 1977 to be at least $40 billion
annually (34), and heart disease is ranked first among causes for
utilization of acute care hospitals (37). About 21 percent of these
cardiovascular deaths occur prior to age 65; 45 percent occur prior to
age 75. Until recently, as the Nation’s population became proportion-
ately older, the crude death rate for the cardiovascular diseases had
increased to a plateau. In contrast, the age-adjusted death rate,
stable until 1940, has since declined (2, 77, 19, 27, 40, 41). During the
1960s, the downward trend in the age-adjusted rate steepened
markedly. Almost two-thirds of the decline between 1950 and 1978
occurred after 1968, a 27 percent decline (Figure 1; Table 2) (7, 78, 22,
23, 24, 27, 30). Death rates for most cardiovascular diseases declined
over the entire period from 1950 to 1978, except for the major
subgroup of coronary heart disease (CHD), for which there was a
consistent rise in mortality in the 1950s and 1960s, followed by a
dramatic decline (Figure 2) (2, 25, 27). The age-adjusted death rate
for all cardiovascular diseases combined was lower by 63 deaths per
100,000 population in 1967 than in 1950. This decrease reflected
declines for cerebrovascular and hypertensive diseases that counter-
acted the increase of 27 deaths per 100,000 population for coronary
heart disease. In the more recent period, 1968 to 1978, the death rate
for all cardiovascular diseases declined by 100 deaths per 100,000
population, with declines for CHD and cerebrovascular diseases
accounting for almost all of the decline. The reversal in mortality
from CHD during 1968-1978 was real, although partly attributable
to the shift in classification of deaths that brought more hyperten-
sive disease deaths into the CHD classification (see the Technical
Notes at the end of this appendix). It was accompanied by an
acceleration in the rate of decline for mortality from the cerebrovas-
cular diseases and a continuation of the percentage declines for other
subgroups of cardiovascular diseases.

The decline in deaths from cardiovascular diseases since 1968 was
striking in comparison with the trends for other causes of death. As
Figure 1 and Table 2 show, the decline since 1968 for all noncardio-

329
~
oe
o

TABLE 1.—Number of deaths from
United States, 1979

all causes and from the major cardiovascular diseases by age,

 

 

Causes of death! Age
(terminology used Under 85 and not
in this report) Total 25 25-34 35-44 45-54 55-64 65-74 75-84 over stated
All causes 1,913,841 113,638 47,941 57,723 135,265 286,966 449,255 493,676 328,725 652
Major cardiovascular \
diseases (390-488) 958,282 3,214 4,209 14,108 49,830 126,410 230,308 300,520 229,510 173
Coronary heart
disease (410-414) 551,365 191 1,289 3,568 31,211 81,722 142,119 169,062 118,112 91
Acute myocardial
infarction (410) 300,462 115 877 5,310 21,694 55,524 88,526 86,262 42,102 42
Other coronary
heart disease (411-414) 250,903 76 412 2,258 9,517 26,198 53,593 82,800 76,010 49
Cerebrovascular
diseases (430-438) 169,488 679 947 2,277 6,061 14,610 34,807 60,324 49,760 23
Hypertensive
diseases (401~405) 31,916 47 210 679 2,102 4,643 7,849 9,567 6,803 16
Diseases of arterioles,
capillaries (440-448 48,284 146 173 302 1,028 3,884 9,888 15,671 17,186 6
Atherosclerosis (440) 28,801 4 5 37 208 1,023 3,736 9,525 14,260 3
Aortic aneurysm (441) 14,031 43 70 127 464 1,968 4,701 4,713 1,937 2
Other (442-448) 5,452 99 98 138 356 893 1,451 1,433 989 1
All other cardio-
vascular (residual) 157,229 2,151 1,590 3,282 9,428 21,551 35,645 45,896 37,649 37
All other causes
of death (residual) 955,559 110,424 43,732 43,615 85,435 160,556 218,947 193,156 99,215 479

 

"Coded to the International Classification of Diseases, Ninth Revision, World Health Organization (45).

SOURCE: National Center for Health Statistics (27).
 

450

-= All Others

RATE PER 100,000 POPULATION

 

 

 

 

250 T T r t v
1950 1955 1960 1965 1970 1975 1960
YEAR

FIGURE 1.—Age-adjusted* death rates for cardiovascular
diseases and all other causes of death, United
States, 1950-1978

* Rates are age-adjusted to the 1940 U.S. population distribution.
SOURCE: National Center for Health Statistica (25, 27}, Bureau of the Census (2).

vascular causes of death combined was only 13 percent. The decline
in all cardiovascular disease deaths since 1963 translates into
289,000 fewer deaths in 1980 than would have occurred had the
death rate remained at its 1970 level. The large decline for CHD
alone translates into 237,000 fewer deaths in 1980 than would have
occurred if the rate had remained at its peak (1963) level (see the
Technical Notes at the end of this appendix). The decline in
cardiovascular disease mortality, therefore, represents a major
contribution to reduced total mortality and improved average life
expectancy (Table 2; Figure 3) (79, 29).

Percentage declines were particularly steep for younger adults, for
women, and for the nonwhite population, but were substantial for all
demographic groups, including the elderly (Table 3). There are some
geographic differences in U.S. cardiovascular mortality trends, but
all areas have experienced substantial declines (13). Moreover, the
United States differs from other countries in this decline, for in most
countries the death rate continues to increase, especially for CHD
among middle-aged men (Figure 4) (46).

331
oe

 

 

 

 

TABLE 2.—Changes in the age-adjusted death rate for all causes, cardiovascular diseases, and all
other causes of death, United States, 1950-1967 and 1968-1978
1950-1967 1968-1978
Change in Change in
rate per Percent rate per Percent
Cause of death 100,000. pop. change 100,000) pop. change
AIl causes -115.9 -13.8 -144.8 ~20.0
Total cardiovascular -63.0 -14.8 -1004 -27.3
Coronary heart disease + 26.6 14.4 64.1 ~26.5
Cerebrovascular diseases -19.1 ~21.5 -26.9 37.7
Hypertensive diseases -33.8 -60.4 -3.1 ~54.3
Other arteriosclerosis -5.1 -53.6 -3.7 -38.5
Rheumatic heart disease -7.5 -315 -2.8 -38,9
Other cardiovascular diseases ~24.1 -36.8 +22 +75
All other causes of death -52.9 “127 ~48.4 ~129

 

SOURCE: Bureau of the Census (7),

National Center for Health Statistics (74, 22 24.25.27 300,
250 4

2254

200 4

1754

RATE PER 100,000 POPULATION

150 4

 

 

T T T T T q
1950 1955 1960 1965 1970 1975 1960

YEAR

FIGURE 2.—Age-adjusted* death rates for coronary heart
disease, United States, 1950-1978

* Rates are age-adjusted to the 1940 U.S. population distribution.
SOURCE: National Center for Health Statistics (25, 27), Bureau of the Census (2).

Methodological Considerations

Measurement of trends in death rates from 1950 to 1979 has been
affected by (1) revisions of the International Classification of Disease
in 1958, 1968, and 1979, (2) revisions of population estimates
following census counts in 1960, 1970, and 1980, and (3) the major
influenza epidemics in 1957, 1963, and 1968, which were years of
unusually high mortality. The Technical Notes that appear at the
end of this appendix discuss the International Classification of
Diseases codes and explains certain adjustments, limitations, and
other points of methodology of these statistics.

Cardiovascular and Noncardiovascular Mortality

The recent decline in cardiovascular mortality has not been
unique. Between 1968 and 1978, the period during which the eighth
revision of the International Classification of Diseases was in use,
the age-adjusted death rate in the United States declined for all
major causes of death except lung cancer and chronic obstructive
pulmonary disease (COPD), i.e., emphysema and chronic bronchitis

333
70

LIFE EXPECTANCY IN YEARS
8
T

‘LL
 ONN

 

0 L 1 1 { l A i j
1840 1960 1960

YEAR OF BIRTH

 

FIGURE 3.—Life expectancy at birth, United States, 1940-
1980

SOURCE: National Center for Health Statistics (19, 29).

(Table 4). Excluding these two causes, mortality from the other
causes of death declined a total of 160 deaths per 100,000 population.
The percentage declines in mortality apply to both middle-aged
persons and those 65 years of age or older. Although the percentage
declines in mortality from diabetes mellitus and influenza or
pneumonia exceed those for the cardiovascular diseases, mortality
declines for the cardiovascular diseases contributed greatly to the
declining overall mortality, accounting for 63 percent overall and 81
percent of the decline in mortality at age 65 and older.

Figure 5 shows that mortality rates from influenza, pneumonia,
and diabetes mellitus have declined since the late 1960s. After a
long-term increase, mortality from cirrhosis of the liver has declined
since about 1975. Thus, the decline in cardiovascular disease
mortality is not unique, but is notable for the magnitude of the
decline in terms of reduced numbers of deaths and the acceleration
in the declining mortality from stroke. The percentage decline in the
death rates from coronary heart disease between 1969 and 1978 were

334
TABLE 3.—Percent changes in death rates’ for selected
causes of death by sex, color, and selected age
groups, United States, 1968-1978

 

 

 

 

 

 

 

 

 

Cardiovascular di (390-458)
Coronary Cerebro-
heart vascular Other cardio- All other
All diseases diseases vascular causes of
Color, sex, age causes Total (410-413) (430-438) diseases death
Both sexes! -20.0 -27.3 -26.5 -37.7 -16.9 -12.9
25-34 -16.2 38.8 87.5 46.9 35.2 -12.9
35-44 -25.4 -35.7 36.9 40.6 -29.6 -21.0
45-54 -18.8 -27.2 26.7 -38.6 -20.0 -12.6
55-64 -18.6 -27.8 -27.8 40.3 -15.1 -9.3
65-74 -19.0 -28.1 -27.8 ~40.7 -11.6 59
75-84 -19.1 -25.9 -24.4 35.5 -16.3 48
854 -21.0 -24.7 -21.1 -33.4 -24.5 -10.1
White males’ -17.7 -24.7 24.5 37.5 -11.1 -10.3
25-34 75 34.5 -31.7 444 -24.2 46
35-44 -22.9 -33.9 36.4 37.5 -19.4 -17.2
45-54 ~19.4 -26.5 -27.0 412 -13.4 -12.7
55-64 ~19.9 -26.4 ~27.0 41.0 -10.4 -12.4
65-74 -17.1 -25.0 24.9 40.0 463 58
15-84 -13.4 ~21.8 -20.0 ~34.8 -9.9 +25
85+ -16.9 -22.9 ~18.7 34.7 -21.8 -19
White females' -20.4 -28.3 -27.3 36.2 -20.7 -12.7
25-34 -18.5 ~38.5 -40.9 417 35.6 ~15.2
35-44 -25.8 34.1 35.6 344 32.2 -23.4
45-54 ~16.5 ~27.2 25.1 32.9 -26.4 -12.0
55-64 -13.5 ~27.3 -27.4 35.0 -18.9 -2.9
65-74 -20.0 -30.7 31.1 40.3 -14.0 44
75-84 -22.1 -27.7 26.0 -35.9 -20.2 89
85+ -23.2 25.9 -22.2 33.6 -26.9 -14.2
Nonwhite males! -21.1 27.1 -24.1 40.0 -20.8 -16.7
25-34 30.3 43.1 40.6 -§2.1 39.1 -28.5
35-44 -28.9 38.2 -37.3 44.8 -35.4 -25.0
45-54 ~20.4 -27.2 24.4 416 -21.5 -15.6
55-64 -18.3 -28.0 -24.4 448 -20.1 -8.5
65-74 -18.4 ~28.4 -25.2 40.8 ~20.7 5.1
75-84 -13.2 -21.7 -18.6 33.5 “115 0.1
854 -74 -15.7 -145 -26.6 3.8 +88
Nonwhite females’ -29.7 -36.0 -33.7 45.9 -28.3 -23.8
25-34 -419 68.1 65.7 58.4 55.0 -37.4
35-44 42.5 53.9 53.5 -60.9 48.1 -36.8
45-54 315 42.3 38.1 52.4 39.7 -23.1
55-64 -29.6 40.0 -39.1 51.4 -25.3 ~17.7
65-74 27.2 36.1 33.9 ATT 23.4 ~11.6
75-84 -19.7 -26.6 -25.4 34.4 -16.4 39
85+ ~13.3 -17.0 -13.9 ~25.9 -12.6 3.9
1 Age-adjusted.

SOURCE: National Center for Health Statistics (27), Bureau of the Census (2).

335
PERCENT CHANGE

-40 -20 0 +20 +40 +60 +80
COUNTRY Fr T T T T T 7
United States
Australia
Japan
Isreal
Canada**

New Zealand
Norway
Belgium***
Fintand**
France**
Italy***
lreland**
Netherlands
Denmark
Scotland
England/Wales
Northern ireland
Austria
Germany, F.R.
Switzerland
Sweden
Hungary
Yugosiavia**
Bulgaria
Romania
Poland

 

FIGURE 4.—Percent of change in the death rate for
coronary heart disease in males, ages 35-74, by
country, 1969-1978*

* Age-averaged rates.

** 1969-1977.

*** 1969-1976.

SOURCE: World Health Organization (46).

similar for the United States, Australia, Japan, and Israel (Figure 4).
These percentage declines in coronary heart disease mortality
among middle-aged men were at least twice the percentage decline
for the noncardiovascular causes of death. The same was true for
women. Elsewhere in the world, cardiovascular mortality did not
decline; its percentage change was not much different from changes
for the noncardiovascular causes of death as a group (46).

Smoking-Related Diseases

The substantial declines in cardiovascular mortality trends are a
long-term pattern that can be correlated to trends in cigarette
smoking in men. Before the 1950s, total mortality in the United

336
LEE

TABLE 4.—Change in age-adjusted death rates for all a

United States, 1968-1978

ges and two age groups by cause of death,

 

 

 

All ages Ages 25-64 Ages 65+
Rate/ 100,000 Percent Rate/ 100,000 Percent Rate/100,000 Percent
Cause of death 1968 1978 Change change 1968 1978 Change change 1968 1978 Change change
All causes 743.8 595.0 -148.8 -20.0 591.4 476.3 -115.1 -19.5 5,519.6 4,453.0 ~1066.6 -19.3
Coronary heart disease 2416 177.5 64.1 -26.5 168.5 120.6 -47.9 -28.4 2,297.4 1,711.6 585.8 -25.5
Cerebrovascular diseases 71.3 44.4 -26.9 -37.7 36.3 21.7 -146 40.2 768.4 483.3 ~285.1 -37.1
Other cardiovascular 55.5 46.1 -9.4 ~16.9 41.0 32.8 8.2 ~20.0 493.4 414.7 -78.7 -16.0
Lung cancer 24.9 33.2 +8.3 +33.3 29.0 37.0 +8.0 +27.6 152.3 214.4 +62.1 +40.8
Other cancer 104.3 98.4 5.9 -5.6 103.3 94.4 8.9 -8.6 723.4 716.4 -7.0 -10
COPD 116 14.5 +29 +25.0 8.8 9.1 +0.3 +3.4 103.2 143.6 +40.4 +39.1
Influenza and pneumonia 26.9 15.1 ~11.8 43.9 15.3 8.0 -7.3 A477 205.7 143.8 -€1.9 ~30.1
Diabetes mellitus 146 10.2 44 -30.1 11.6 8.1 -3.5 -30.2 126.0 88.7 -37.3 ~29.6
Cirrhosis of the liver 13.9 12.4 -156 -10.8 22.5 19.6 -2.9 -12.9 36.9 37.3 +0.4 +11
Accidents, poisonings,
and violence 76.5 66.7 -9.8 -12.8 84.7 73.6 -111 -13.1 158.6 ‘111.2 ATA -29.9
All other causes 102.7 76.5 -26.2 -25.5 70.4 51.4 -19.0 ~27.0 454.3 388.0 -66.3 -146

SOURCE: National Center for Health Statistics (27),

Bureau of the Census (2).

i
 

    
   

 

 

 

400 T T T T T
Coronary Heart Disease
Other Cancer
80 Cerebrovascular Diseases 7
z 60 F-
Qo .
5 Other Cardiovascular 7
5 40 Diseases ***
&
; |. Influenza and Pneumonia Lung Cancer
a . a
2 Pw of ft Se
a / PX ‘ hy
8 * ‘ i ww met \
Bp awe Ne
my ae at ‘
w a wey
E ~~” Diabetes -—— Kd
a PL acer eee ee ESC
- 5 . ~,
Cirrhosis ore se]
ae He.
10- oreo” 24
Le ee if =
8 ro ow Bronchitis, Emphysema, 2
a Pal and Asthma 4
Z
6e -*" +
a f -~
i
Z
ae 4
5 -
2 1 i 1 t 1
1950 1955 1960 1965 1970 1975
YEAR

FIGURE 5.—Age-adjusted* death rates for the leading
causes of death, United States, 1950-1978

* Rates are age-adjusted to the 1940 U.S. population distribution.
** This break in trend is due to a revision of the International Classification of Diseases. It affects the

cardiovascular diseases more than other causes of death.
*** Primarily hypertensive, peripheral, and rheumatic heart disease.
SOURCE: National Center for Health Statistics (18, 22, 23, 27, 30), Bureau of the Census (/, 2).

States declined rapidly, as the decreased mortality from infectious
and parasitic diseases masked an increasing mortality rate from
diseases associated with smoking—especially CHD, lung cancer, and
COPD. Between 1955 and 1965, the total mortality decline stopped
for men and slowed for women, partly because the numbers of deaths

338
from the smoking-related diseases of lung cancer, chronic obstructive
lung disease, and cardiovascular disease were increasing quite
substantially (especially among men), cancelling the gains made in
other causes of death. Percentage increases were greater for lung
cancer and COPD than for CHD, but compared with rates for CHD,
death rates for these two diseases were lower in absolute terms.
Since the mid-1960s, the remarkable decline in the coronary death
rate has resulted in a new decline in total mortality. Although death
rates for lung cancer and COPD are still increasing, the rate of
increase is slowing, and in recent years, there is a suggestion of a
reversal in lung cancer mortality among the younger cohorts (39).

Coronary Heart Disease Mortality

The age-adjusted death rate for CHD increased 19 percent from
1950 to 1963, peaked in 1963, and then declined 30 percent from 1963
to 1979 (Figure 2). (This assumes good comparability of cause-of-
death assignment and classification to CHD for 1963 and 1979. See
the Technical Notes at the end of this appendix.) The reversal of the
trend was gradual; however, the inflection point was the mid-1960s.
During the period between 1968 and 1978, when CHD mortality was
classified according to the eighth revision of the International
Classification of Diseases, the age-adjusted death rate declined 26.5
percent (Table 3). The decline was greatest at younger ages, ranging
from 38 percent for ages 25 to 34 to 21 percent for age 85 and older.
Nonwhite females experienced the largest decline of any sex/color
group—34 percent, with declines exceeding 50 percent in persons 45
years of age or younger. The mortality trends for CHD displayed in
Figure 6 show a striking change from the differential trends among
the four sex/color groups prior to 1968 and remarkably similar
downward slopes since then. Rates for white and nonwhite females
appear to have begun their current decline in about 1964. The
earliest that the rates for white and nonwhite males began their
current decline was 1967, following a brief plateau. Further, age-
specific CHD mortality trends prior to the current decline showed
greater differences than during the current decline (Figure 7). As
stated above, however, declines continue to be steeper for younger
than for older persons. The decline in CHD mortality is substantial
in every State in the country, but is less marked in Appalachia, an
area of relatively high CHD mortality. There is also some evidence
that for life insurance policyholders, constituting a higher socioeco-
nomic group than the general population, declines are steeper than
for the general population (15).

A breakdown of CHD deaths into deaths from acute myocardial
infarction and deaths from other types of CHD is possible, but it is
not known to which group most sudden or out-of-hospital CHD

339
White Males

een oom
-——_——

Non-White Males

RATE PER 100,000 POPULATION

 

1950 1955 1960 1965 1970 1975 1980
YEAR

FIGURE 6.—Age-adjusted* death rates for coronary heart
disease by sex and color, all ages, United
States, 1950-1978

* Rates are age-adjusted to the 1940 U.S. population distribution.
SOURCE: National Center for Health Statistics (25, 27), Bureau of the Census (2).

deaths are classified (Table 1). A much steeper decline in the death
rate for acute myocardial infarction than for other CHD occurred
during the 1968-1978 period (Figure 8). More information is needed
before it can be determined what significance to ascribe to this
difference.

Other Cardiovascular Disease Mortality

The leading cause of death after heart disease and cancer is stroke,
a cerebrovascular disease and a major component of cardiovascular
diseases. The underlying process for about 80 percent of all strokes is
arteriosclerosis, and hypertension is a major contributing factor (38).
However, the age-adjusted death rate for stroke has been declining
since before 1930, and has shown an accelerated downward trend in
recent years (Figure 9). In the time period 1950-1967 , the age
adjusted death rate for cerebrovascular disease declined almost 22
percent; this rate of decline accelerated during the time period 1968—
1978 to 38 percent (Table 2). The death rate declined 1.0 percent per
year in the 1950s and 1.8 percent per year in the 1960s. As is the case
for CHD, the trend for stroke mortality since 1968 has been

340
10,000
85+

75-84
65-74

1000
55-64

45-54

35-44

RATE PER 100,000 POPULATION

 

1950 1955 1960 1965 1970 1975 1980

YEAR

FIGURE 7.—Age-adjusted* death rates for coronary heart
disease by age, white males, United States,
1950-1978

* Rates are age-adjusted to the 1940 U.S. population distribution.
SOURCE: National Center for Health Statistics (25, 27), Bureau of the Census (2).

uniformly downward for the sex/color groups, with declines being
especially steep for nonwhites and younger adults (2, 21, 23, 27).

The age-adjusted death rate for hypertensive disease declined an
average of 4.9 percent per year in the 1950s, 5.0 percent between
1960 and 1967, and 7.2 percent between 1970 and 1978. Similar to
the trend for stroke, there is a steepening of the long-term decline in
mortality from hypertensive disease, with recent declines being
steeper among nonwhites than among whites. Large declines for the
general arteriosclerosis category and for all other cardiovascular
diseases combined occurred throughout the 1950-1978 period, in-
cluding a decline in mortality rates for aortic aneurysm from 1968 to
1978.

Incidence and Case-Fatality

A decline in mortality rates may reflect changes in either the
number of new and recurrent coronary attacks (incidence) or the
survivorship from such attacks (case-fatality). Reliable national
statistics of either incidence or case-fatality are not available.
National prevalence and hospital discharge statistics are limited as

341
 

 

RATE PER 100,000 POPULATION

50 4 = Acute MI
= = Other CHD

 

 

 

1968 1970 1972 1974 1976 1978
YEAR

FIGURE 8.—Age-adjusted* death rates for acute myocardial
infarction and other CHD, United States, 1968-
1978

* Rates are age-adjusted to 1940 U.S. population distribution.
SOURCE: National Center for Health Statistics (27), Bureau of the Census (2.

measures of these trends. Reliance therefore must be placed primari-
ly on available community- or hospital-based studies.

In a study of male employees of the DuPont company in Delaware,
the incidence rate of acute myocardial infarction was 18 percent
lower in the 1973-1979 period than in the 1957-1964 period (33).
Overall 30-day case-fatality rates and the proportion of sudden
deaths did not change significantly. However, beginning about 1969,
the 30-day mortality among persons who survived 24 hours after the
attack declined significantly.

In the Kaiser-Permanente Medical Care Program in the San
Francisco area, the proportion of persons hospitalized each year
(rate/1,000 subscribers) for acute myocardial infarction declined 27
percent between 1971 and 1977 (5). The proportion of persons
hospitalized for any coronary heart disease event declined 18
percent. The decline was seen in both first and recurrent events and
did not result from shifting to noncoronary diagnoses. No clear trend
could be ascertained in the proportion of persons who died from
acute myocardial infarction of all persons hospitalized for this
disease each year.

In a study of the population of Rochester, Minnesota, there was no
change in the incidence of initial manifestations of coronary heart

342
80 +

70 4

RATE PER 100,000 POPULATION
8
1
‘

 

30

 

v q q t qT od
1950 1955 1960 1965 1970 1975 1980

YEAR

FIGURE 9.—Age-adjusted* death rates for cerebrovascular
diseases, all ages, United States, 1950-1978

* Rates are age-adjusted to the 1940 U.S. population distribution.
SOURCE: National Center for Health Statistics (27, 23, 27), Bureau of the Census (2).

disease between 1950 and 1969 (3). However, the case-fatality rate,
based on sudden, unexpected deaths and myocardial infarction
deaths under 30 days, was 34 percent in the 1970-1975 period,
whereas it had been 47 percent in the 1950-1955 period. In contrast,
during 1971-1978, males under 65 years of age enrolled in the
Health Insurance Plan of Greater New York who had recovered
from a first myocardial infarction showed no better survival over 4.5
years than did a comparable group during 1961-1970 (43).

One study provides secular trends on the severity of coronary
atherosclerosis between 1960-1964 and 1968-1972 (36). Autopsy
findings in this New Orleans study reveal that the extent of intimal
surface covered by raised lesions decreased significantly between

343
1960-1964 and 1968-1972 among white males 25 to 44 years of age,
and also decreased slightly among black males.

In the Kaiser-Permanente study, the proportion of persons hospi-
talized for cerebral thrombosis dropped 64 percent between 1971 and
1977, most of the drop occurring after 1973. The decline for all
cerebrovascular diseases combined was 15 percent. In the Rochester,
Minnesota, population there was a 45 percent decline in the
incidence of stroke between 1945 and 1974, with reductions more
pronounced in the elderly (6). The Framingham study observed a
lower incidence rate for stroke among women (but not among men)
followed since 1962, as compared with women followed since 1950
(70).

Trends in national hospital discharge statistics from the National
Center for Health Statistics are available, but difficult to interpret.
Discharge rates for both acute myocardial infarction and stroke
between 1970 and 1978 show no increase in incidence of acute events
(Figure 10) (26, 37). These data, however, are not inconsistent with a
decline in CHD incidence, because patients are increasingly being
admitted for cardiac pacemaker insertion and replacement, for
catheterizations, and for other diagnostic and therapeutic proce-
dures (Table 5). Figure 11 shows annual data on hospital case-fatality
rates. Despite annual fluctuations, the trend in case-fatality rates
from 1970 to 1978 is clearly downward for acute myocardial
infarction. This could result from an increased tendency to admit
milder cases not previously hospitalized, from a real improvement in
therapeutic efficacy, or from a mixture of both.

Risk Factors and Treatment
Risk Factor Reduction

As is discussed elsewhere in this Report, three major modifiable
risk factors—cigarette smoking, hypertension, and hypercholesterol-
emia—are statistically significant contributors to cardiovascular
risk for both men and women (Table 10) (14). Cigarette smoking,
hypertension, and a high serum cholesterol each have been found to
increase coronary heart disease risk. The nationwide efforts to
reduce cigarette smoking, to control high blood pressure, and to
avoid foods high in saturated fats (4) have reduced the levels of these
risk factors during the past 15 years (Tables 6, 7, 8, and 9) (24, 28, 32).
The reduction in each of the risk factors coincides with the observed
decline in CHD mortality.

Attempts have been made to estimate how much of the reduction
in cardiovascular disease mortality can be ascribed to observed
reductions in risk factor levels (11, 12, 35). Findings have not been
definitive because of data limitations. It has not been possible to
quantify or to rank the separate contributions of a reduction in any

344
RATE PER 10,000 POPULATION

 

100

40

 

Other CVD

Other CHD

AMI

Cerebrovascular

] i | 1 1 L l

 

 

1970

1972 1974

YEAR

1976 1978

FIGURE 10.—Rate of hospital discharges for major

components of cardiovascular disease, ages
45-65, United States, 1970-1978

SOURCE: National Center for Health Statistics (26), Thom et al. (37).
TABLE 5.—Number of selected cardiovascular surgical
procedures, United States, 1970, 1975, 1980

 

 

Procedure 1970 1975 1980

Coronary bypase' 14,000 57,000 137,000
Cardiac valves? 16,000 23,000 35,000
Catheterizations* 77,000 189,000 348,000
Pacemaker insertions 4é 24,000 60,000 143,000
All vascular and cardiac * 506,000 888,000 1,484,000

 

*ICD/8 codes 29.8; ICD/9 codes 36.1-36.3.

*ICD/8 codes 29.2-29.4; ICD/9 codes 35.1,35.2,35.99,

*ICD/8 codes 30.2; ICD/9 codes 3721-3723.

“ICD/8 codes 30.4; ICD/9 codes 37.7.

*ICD/8 codes 24-30; ICD/9 codes 35.1-40.5.

“Excludes replacements.

SOURCE: National Center for Health Statistics (26), Thom (37).

one risk factor to the mortality decline, but one analysis concluded
that “elimination of smoking would have the greatest impact on
CHD death rates” (12). The extent to which changes in these risk
factors may have contributed to the decline in mortality depends, in
part, on their prevalence in the U.S. population, and thus, on the
reduction in prevalence that has taken place in recent years.

An estimated 38.3 percent of adult men and 29.2 percent of adult
women smoke cigarettes, that is, 50 to 55 million persons as of 1980
(Table 6). These percentages represent large declines from the 52.4
percent and 34.1 percent, respectively, in 1965 (28). Table 6 gives the
age-adjusted and age-specific rates that correspond to these crude
rates of smoking. In a 1976 to 1980 survey, an estimated 22 percent
of persons 25 to 74 years of age, about 25 million persons, had
hypertension, i.e., a systolic blood pressure of 160 mm Hg or greater,
a diastolic blood pressure of 95 mm Hg or greater, or were on
antihypertensive medication (Table 8) (32). Although the prevalence
rate in 1960-1962 was about the same (20 percent), a much larger
proportion of persons with hypertension in the more recent period
were aware of it (73 vs. 49 percent), were on treatment for it (56 vs.
31 percent), and had it controlled (34 vs. 16 percent). Ina survey in
1971-1974, an estimated 21.9 percent of persons 18 to 74 years of age,
28 million persons, had serum cholesterol levels of 260 mg/100 ml or
greater (24). After adjusting these crude rates to make them
comparable by age to estimates in the 1960-1962 survey, the
percentage of persons at that level or greater was less than in the
1960-1962 survey, although the decline was not Statistically signifi-
cant for all age/sex groups (Table 9). As of 1979, there were about 5
million adults with diabetes mellitus, 3 percent of the adult
population (28). There apparently has been no reduction in preva-
lence in recent years.

346
 

 

 

 

x0 Fr Acute Mi 65+
Q
w
gS
c
<
x
BZ OF
a
e
2
7]
9
«
2

Acute MI 45-64
10 F
Chwonic CHD 65 +
Chronic CHD 45-64
0 1 i 1 L 1 j i
1970 1971 1972 1973 1974 1975 1976 1977 1978
YEAR

FIGURE 11.—Hospital case-fatality rate for acute
myocardial infarction and chronic CHD,
United States, 1970-1978

NOTE: First-listed diagnosis on discharge: ICD/8 code 410 for acute MI, and 412 for chronic CHD.
SOURCE: National Center for Health Statistics (26), Thom et al. (37).

The correlation of independent risk factors to cardiovascular
disease risk is shown in Table 10. The documented changes in risk
factors in Tables 6-9 suggest that the decline in the prevalence of
cigarette smoking, which affected the greatest number of people,
may have contributed more to the decline than did changes in the
other risk factors. This assertion depends on the quality of data on

347
the prevalence of smoking, the changes in prevalence of smoking,
and the relative strength of the association between smoking and
CHD risk, as well as evidence that cessation of smoking lowers the
risk of acute and recurrent myocardial infarction mortality.

Impact of Improved Treatment

Improvements have been made in recent years in the medical care
of the coronary patient prior to, during, and after hospitalization.
Treatment is now more aggressive and sophisticated, and the
improved management techniques are more generally available
throughout the country. Today’s coronary patient has a much better
chance of arriving alive at a hospital and at an earlier stage of the
episode than was the case a decade or two ago (7). Once hospitalized,
the patient is monitored for arrhythmias and changes in cardiac
function, usually in a coronary care unit. Catheterizations and
coronary artery bypass surgery have been performed with greatly
increased frequency in recent years (Table 5). It is likely that
improved treatment in a hospital has reduced the case-fatality rate
of these patients (Figure 11). The post-discharge treatment is better
managed today. The coronary patient with angina pectoris or
hypertension receives more aggressive and effective treatment;
antiarrhythmic drug therapies are widely used; and many patients
are advised to stop smoking, modify their diet, and lose weight.
Although documentation of the occurrence in time of many of these
treatment improvements is incomplete, most were made in the 1960s
and 1970s.

Trends and Associated Factors

The reversal of the death rate for CHD and the acceleration of the
decline for stroke have coincided over time with increased efforts in
primary and secondary prevention. These efforts include the anti-
smoking campaigns since 1964, the nationwide campaign against
hypertension since 1972, a trend away from saturated fats in the
diet, and changes in treatment, such as expanded utilization of
coronary care units, cardiac surgery, cardiac catheterization, and
pacemakers (8). The public is now more aware of cardiovascular risk
factors, especially cigarette smoking, hypertension, and elevated
serum cholesterol. Also, when a heart attack or stroke occurs,
today’s patient generally receives more aggressive medical manage-
ment (7, 9).

Trends and Smoking

The proportion of both cigarette smokers and CHD mortality
increased until the mid-1960s and then declined markedly. Tempo-

348
TABLE 6.—Percentage distribution of adult current and

former cigarette smokers, according to sex,
race, and age, in 1965, 1976, and 1980

 

Current smoker’ (percent)

Former smoker (percent)

 

Sex, race, and age 1965 1976 1980? 1965 1976 1980?
MALE

Total 34
All ages > 20° §2.1 416 37.9 20.3 29.6 30.5
20-24 59.2 45.9 39.7 9.0 12.2 12.1
25-34 60.7 48.5 43.1 14.7 18.3 20.6
35-44 58.2 476 42.6 20.6 27.3 27.6
45-64 519 413 40.8 24.1 37.1 36.9
>65 28.5 23.0 17.9 28.1 44.4 47.4

White
All ages > 20° 513 41.0 37.1 21.2 30.7 31.9
20-24 58.1 45.3 39.0 9.6 13.3 12.2
25-34 60.1 47.7 42.0 15.5 18.9 219
35-44 57.3 46.8 42.4 215 28.9 28.8
45-64 513 40.6 40.0 25.1 38.1 38.4
> 65 27.7 22.8 16.6 28.7 45.6 50.1

Black
All ages > 20* 59.6 50.1 449 12.6 20.2 20.6
20-24 67.4 52.8 45.5 3.8 41 10.6
25-34 68.4 59.4 52.0 6.7 11.8 11.9
35-44 67.3 58.8 44.2 12.3 13.8 21.2
45-64 579 49.7 48.8 15.3 28.6 26.3
> 65 36.4 26.4 27.9 21.5 33.0 26.6

FEMALE

Total 34
All ages > 20* 34.2 32.5 29.8 8.2 13.9 15.7
20-24 419 34.2 32.7 73 10.4 11.0
25-34 43.7 37.5 31.6 9.9 12.9 14.4
35-44 43.7 38.2 34.9 9.6 15.8 18.9
45-64 32.0 34.8 30.8 8.6 15.9 17.1
> 65 9.6 128 16.8 45 11.7 14.2

White
All ages > 20* 34.5 32.4 30.0 85 14.6 16.3
20-24 419 34.4 33.3 8.0 114 12.6
25-34 43.4 37.1 31.6 10.3 13.7 14.7
35-44 43.9 38.1 35.6 9.9 17.0 20.2
45-64 32.7 34.7 306 8.8 16.4 17.4
>65 9.8 13.2 17.4 45 115 14.3

Black
All ages > 20° 32.7 34.7 30.6 59 10.2 11.8
20-24 44.2 34.9 32.3 25 5.0 2.2
25-34 478 42.5 34.2 6.7 89 11.6
35-44 42.8 413 36.5 7.0 9.6 12.5
45-64 25.7 38.1 34.3 6.6 11.9 14.1
>65 71 9.2 9.4 45 13.3 14.1

 

‘ A current amoker has smoked at least 100 cigarettes and now smokes; includes occasional smokers.
* Final estimates. Based on data for the last 6 months of 1980.

5 Base of percentage excludes persons with unknown smoking atatus.

‘Includes all other races not shown separately.

"Age adjusted by the direct method to the 1970 civilian noninstitutionalized population using 5 age groupe.

NOTE: Percentages do not add up to 100 because of “never smokers” in the survey population.

SOURCE: Data from the National Health Interview Survey, National Center for Health Statistics, 1965, 1976,

and 1980, based on household interviews with a sample of the civilian noninstitutionalized population.

rally, the beginning of the decline in CHD mortality closely followed
the decline in prevalence of smoking after the issuance of the first

349
TABLE 7.—Change in percentage of current cigarette
smokers and of those who smoke 25 or more
cigarettes per day, by color, sex, and age,
United States, 1965 to 1980

 

 

 

All Smoke 25 or
current more cigarettes
Color, sex, and age smokers per day
White men, age 20+ -27.0 +07
20-24 31.8 9.2
25-34 -30.6 -12.1
35-44 -26.5 -2.1
45-64 -21.6 +18.2
65 and older 87.5 +143
Black men, age 20+ —25.8 -12.5
20-24 -29.4 -111
25-34 ~23.1 -24.2
35-44 -37.6 32.1
45-64 -19.7 +22.2
65 and older -20.6 +166.7
White women, age 20+ -13,7 +46.2
20-24 -21.2 +386
25-34 -27.2 +16.7
35-44 -18.9 +55.6
45-64 -7.6 +66.0
65 and older +786 +257.1
Black women, age 20+ -14.0 +50.0
20-24 -28.7 unknown?
25-34 31.2 +26.2
35-44 -19.6 +15,4!
45-64 31.1 +3444!
65 and older +22.5 unknown!

 

* Figure does not meet standards of reliability or precision.
SOURCE: National Center for Health Statistica (28).

Report of the Surgeon General on The Health Consequences of
Smoking. The same phenomenon has been reported in other
countries as well (37).

The decline for CHD mortality is occurring among adults of all
age, color, and sex groups, a pattern similar to that of the reduction
in the proportion of the population who are cigarette smokers. The
mortality decline is steeper among younger adult age groups, which
is consistent with not starting to smoke or early smoking cessation.
Since 1950 for males and 1960 for females, each succeeding sex
cohort has experienced a lower peak prevalence of smoking (42). The
evidence of more rapid declines in mortality for persons on a higher

350