1. Cardiovascular Epidemiology
and Prevention
Nathan D. Wong, PhD, FACC, FAHA
Professor and Director, Heart Disease
Prevention Program, Division of
Cardiology, University of California, Irvine
President, American Society of Preventive
Cardiology
4. Definitions
• CORONARY ARTERY DISEASE (CAD) or
CORONARY HEART DISEASE (CHD) (often
broadly referred to as ISCHEMIC HEART
DISEASE (IHD): primarily myocardial
infarction and sudden coronary death,
broader definition may include angina
pectoris, atherosclerosis, positive
angiogram, and revascularization
(perceutaneous coronary interventions, or
PCI such as angioplasty and stents)
• CARDIOVASCULAR DISEASE or CVD
includes CHD, cerebrovascular disease,
peripheral vascular disease, and other
cardiac conditions (congenital,
arrhythmias, and congestive heart failure)
11. 550
Deaths in Thousands
500
450
400
350
79 80 85 90 95 00 06
Years
Males Females
CVD disease mortality trends for males and females
(United States: 1979-2006).
Source: NCHS and NHLBI.
12. 7
6
Discharges in Millions
5
4
3
2
1
0
70 75 80 85 90 95 00 06
Years
Hospital discharges for cardiovascular diseases.
(United States: 1970-2006). Note: Hospital discharges include
people discharged alive, dead and status unknown.
Source: NCHS and NHLBI.
19. Coronary Heart
Disease
Stroke
14
4
7 HF*
51 High Blood Pressure
7
17 Diseases of the
Arteries
Other
Percentage breakdown of deaths from cardiovascular diseases
(United States: 2006) * - Not a true underlying cause.
Source: NCHS.
20. 16
13.8
14 12.2
Percent of Population
12
9.3
10
8
6 4.8
4 2.2
2 1.2
0.1 0.2
0
20-39 40-59 60-79 80+
Men Women
Prevalence of heart failure by age and sex
(NHANES: 2005-2006). Source: NCHS and NHLBI.
21. 700
Discharges in Thousands
600
500
400
300
200
100
0
79 80 85 90 95 00 06
Years
Male Female
Hospital discharges for heart failure by sex.
(United States: 1979-2006). Source: NHDS/NCHS and NHLBI.
Note: Hospital discharges include people discharged alive, dead
and status unknown.
22. Development of Atherosclerotic
Plaques
Fatty streak
Normal
Lipid-rich plaque
Foam cells
Fibrous cap
Lipid core
Thrombus
Ross R. Nature. 1993;362:801-809.
23. PDAY: Percentage of Right Coronary Artery
Intimal Surface Affected With Early Atherosclerosis
30 Raised lesions 30
Men Fatty streaks
Women
20 20
10 10
0 0
Intimal 15-19 20-24 25-29 30-34 15-19 20-24 25-29 30-34
surface 30 White White
30
(%)
20 20
10 10
0 0
15-19 20-24 25-29 30-34 15-1920-2425-2930-34
Black Black
Age (y)
PDAY= Pathobiological Determinants of Atherosclerosis in Youth.
Strong JP, et al. JAMA. 1999;281:727-735.
24. Most Myocardial Infarctions Are Caused
by Low-Grade Stenoses
Pooled data from 4 studies: Ambrose et al, 1988; Little et al, 1988; Nobuyoshi et al, 1991; and Giroud et al,
1992.
(Adapted from Falk et al.)
Falk E et al, Circulation, 1995.
25. Coronary Remodeling
Progression
Expansion
Compensatory expansion overcome:
maintains constant lumen lumen narrows
Normal Minimal Moderate Severe
vessel CAD CAD CAD
(Adapted from Glagov et al.)
Glagov et al, N Engl J Med, 1987.
Med,
26. Atherosclerotic Plaque Rupture and
Thrombus Formation
Growth of thrombus
Intraluminal thrombus
Blood Flow
Intraplaque thrombus Lipid pool
Adapted from Weissberg PL. Eur Heart J Supplements
1999:1:T13–18
27. Features of a Ruptured
Atherosclerotic Plaque
• Eccentric, lipid-rich
• Fragile fibrous cap
• Prior luminal
obstruction < 50%
• Visible rupture
and thrombus
Constantinides P. Am J Cardiol. 1990;66:37G-40G.
28. Vulnerable Versus Stable
Atherosclerotic Plaques
Vulnerable Plaque
Lumen Lipid •Thin fibrous cap
Fibrous Cap
Core •Inflammatory cell infiltrates:
proteolytic activity
•Lipid-rich plaque
Stable Plaque
•Thick fibrous cap
Lumen Lipid •Smooth muscle cells:
Core
more extracellular matrix
Fibrous Cap
•Lipid-poor plaque
Libby P. Circulation. 1995;91:2844-2850.
29. Correlation of CT angiography of the
coronary arteries with intravascular
ultrasound illustrates the ability of MDCT
to demonstrate calcified and non-calcified
coronary plaques (Becker et al., Eur J
Radiol 2000) Non-calcified, soft, lipid-rich plaque in
left anterior descending artery (arrow)
(Somatom Sensation 4, 120 ml Imeron
400). The plaque was confirmed by
intravascular ultrasound (Kopp et al.,
Radiology 2004)
30.
31. Concept of cardiovascular
“risk factors”
Age, sex, hypertension, hyperlipidemia, smoking, diabetes,
(family history), (obesity)
Kannel et al, Ann Intern Med 1961
32. Major Risk Factors
• Cigarette smoking (passive smoking?)
• Elevated total or LDL-cholesterol
• Hypertension (BP ≥ 140/90 mmHg or on
antihypertensive medication)
• Low HDL cholesterol (<40 mg/dL)†
• Family history of premature CHD
– CHD in male first degree relative <55
years
– CHD in female first degree relative <65
years
• Age (men ≥ 45 years; women ≥ 55 years)
†
HDL cholesterol ≥60 mg/dL counts as a “negative” risk factor; its
presence removes one risk factor from the total count.
33. Other Recognized Risk
Factors
• Obesity: Body Mass Index (BMI)
– Weight (kg)/height (m2)
– Weight (lb)/height (in2) x 703
• Obesity BMI >30 kg/m2 with overweight
defined as 25-<30 kg/m 2
• Abdominal obesity involves waist
circumference >40 in. in men, >35 in. in
women
• Physical inactivity: most experts
recommend at least 30 minutes moderate
activity at least 4-5 days/week
36. ___________________________________________________________
_
Lifetime Risk of Coronary Heart Disease
in the Framingham Study
______________________________________________________________
Men Women
At age 40 years: 48.6% 31.7%
At age 70 years: 34.9% 24.2%
_________________________________________________________________
Lloyd-Jones et al. Lancet 1999; 353:89-92
37. ____________________________________________________________
First Coronary Events: Framingham
Study
________________________________________________________
Percent as Specified Event
Myocardial Angina Sudden
Infarction Pectoris Death
Age Men Women Men Women Men Women
35-64 43% 28% 41% 59% 9% 4%
65-84 55% 44% 28% 41% 11% 7.4%
____________________________________________________________
Framingham Study 44 year follow-up.
38. Estimated 10-Year CHD Risk in
55-Year-Old Adults According to Levels
of Various Risk Factors
Framingham Heart Study
A B C D
Blood Pressure (mm Hg) 120/80 140/90 140/90 140/90
Total Cholesterol (mg/dL) 200 240 240 240
HDL Cholesterol (mg/dL) 50 50 40 40
Diabetes No No Yes Yes
Cigarettes No No No Yes
mm Hg = millimeters of mercury
mg/dL = milligrams per deciliter of blood
Source: Circulation 1998;97:1837-1847.
39. Estimated 10-Year Stroke Risk in 55-
Year-Old Adults According to Levels of
Various Risk Factors
Estimated 10-Year Rate (%)
Framingham Heart Study
30 27
25 22.4
19.1
20
14.8
15
10 8.4
5.4 6.3
5 4 3.5
2.6 2
1.1
0
A B C D E F
Men Women
A B C D E F
Systolic BP* 95-105 130-148 130-148 130-148 130-148 130-148
Diabetes No No Yes Yes Yes Yes
Cigarettes No No No Yes Yes Yes
Prior Atrial Fib. No No No No Yes Yes
Prior CVD No No No No No Yes
Source: Stroke 1991;22:312-318. *BP in millimeters of mercury (mmHg)
40. Offspring CVD Risk by Parental CVD Status:
Framingham Study
Parental CVD <55
Risk Ratio men, <65 Women
2.5
2.5 NONE
MATERNAL
2
2 PATERNAL
2.2
1.5
1.7 1.7 1.7
1
1
1.0 1.0
0.5
0.5
0
0
Men
MEN Women
WOMEN
Adjusted for: age, total/HDL Chol. ratio, SBP, smoking, diabetes, BMI
41. Risk imposed by a strong family
history of heart attacks varies widely
depending on the burden of
modifiable risk factors
Multivariable Risk
48. ________________________________________________________
CK Friedberg on Hypertension:
___________________________________________________________
Diseases of the Heart 1996
“There is a lack of correlation in
most cases between the severity
and duration of hypertension and
development of cardiac
complications.”
______________________________________________________________
_
49.
50.
51. Relation of Non-Hypertensive Blood
Pressure to Cardiovascular Disease
Vasan R, et al. N Engl J Med 2001; 345:1291-1297
10-year Age- Adjusted Cumulative Incidence
12% Hazard Ratio*
<120/80 mm Hg
120-129/80-84 mm Hg SBP Women Men
10%
130-139/85-89 mm Hg 10.1
<120/80 1.0 1.0
8% 120-129 1.5 1.3
7.6 130-139 2.5 1.6
6%
5.8 H.R. adjusted for age, BMI,
4% Cholesterol, Diabetes and
4.4
smoking *P<.001
2.8
2%
1.9
0%
Women Men
Framingham Study: Subjects Ages 35-90 yrs.
53. 90 82.3
78.8 79.0
Percent of Population With
80 69.1 70.1
74.7
67.6
70
Hypertension
60 52.1
46.5
50 45.4 46.1
40 35.2
30
20
10
0
Awareness Treatment Controlled
Total Population NH Whites NH Blacks Mexican Americans
Extent of awareness, treatment and control of high blood
pressure by race/ethnicity (NHANES : 2005-2006).
Source: NCHS and NHLBI.
54. ______________________________________________________________
_
CK Friedberg on Hypertension
______________________________________________________________
Diseases of the Heart 1966 _
“Hypertension imposes a load on
the heart which for many years
may be compensated by left
ventricular hypertrophy”
55. ______________________________________________________________
CVD Risk Imposed by ECG-LVH _
Framingham Study 36-yr. Follow-up
_______________________________________________________________
Age-adjusted Risk Excess Risk
Rate per 1000 Ratio per 1000
Age Men Women Men Women Men Women
35-64 164 135 4.7*** 7.4*** 129 117
65-94 234 235 2.8*** 4.1*** 51 178
_____________________________________________________________
Biennial Rate per 1000. CVD=CHD, stroke,
peripheral vascular disease, heart failure
***P<0.001
56. ___________________________________________________________
_
Smoking Statement Issued in 1956 by
American Heart Association
___________________________________________________________
“It is the belief of the committee that much
greater knowledge is needed before
any conclusions can be drawn
concerning relationships between
smoking and death rates from coronary
heart disease. The acquisition of such
knowledge may well require the use of
techniques and research methods that
have not hitherto been applied to this
__________________________________________________________
problem.” _
57. CHD Risk by Cigarette Smoking. Filter
Vs. Non-filter. Framingham Study. Men
<55 Yrs.
14-yr.
Rate/1000
250
Non-Smoker
200 Reg. Cig. Smoker
206
210 Filter Cig. Smoker
150
210
100 119
112
50 59
0
Total CHD Myocardial
Infarction
61. Diseases of The Heart
Charles K Friedberg MD, WB
Saunders Co. Philadelphia, 1949
________________________________________________________________
“The proper control of diabetes is
obviously desirable even though
there is uncertainty as to whether
coronary atherosclerosis is more
frequent or severe in the
uncontrolled diabetic”
______________________________________________________________
62. Risk of Cardiovascular Events in Diabetics
Framingham Study
________________________________________________________________
_
Age-adjusted
Biennial Rate Age-adjusted
Per 1000 Risk Ratio
Cardiovascular Event Men Women Men Women
Coronary Disease 39 21 1.5** 2.2***
Stroke 15 6 2.9*** 2.6***
Peripheral Artery Dis. 18 18 3.4*** 6.4***
Cardiac Failure 23 21 4.4*** 7.8***
All CVD Events 76 65 2.2*** 3.7***
________________________________________________________________
Subjects 35-64 36-year Follow-up **P<.001,***P<.0001
_
66. Skepticism About Importance of Obesity
Keys A, Aravanis C, Blackburn H, et al. Ann Intern Med
1972; 77:15-27.
Concluded that all the excess risk of coronary heart
disease in the obese derives from its atherogenic
accompaniments, illogically leaving the impression that obesity
is therefore unimportant.
Mann GV. N Engl J Med 1974; 291:226-232.
“The contribution of obesity to CHD is either small or
non-existent. It cannot be expected that treating obesity is
either logical or a promising approach to the management of
CHD”.
Barrett-Connor EL. Ann Intern Med 1985; 103:1010-1019
NIH consensus panel is equivocal about the role of
obesity as a cause of CHD.
67. Relation of Weight Change to Changes in
Atherogenic Traits: The Framingham Study
Frantz Ashley, Jr. and William B Kannel
J Chronic Dis 1974
“Weight gain is accompanied by atherogenic alterations in
blood lipids, blood pressure, uric acid and carbohydrate
tolerance.”
“It seems reasonable to expect that correction of overweight
will improve the coronary risk problem.”
“Avoidance of overweight would seem a desirable goal in the
general population if the appalling annual toll from disease
is to be substantially reduced.”
70. Risk Factor Sum and Obesity
Framingham Study
3 (1971-74) and (1989-93)
2.4 (1971) (1989)
Risk Factor Sum
Risk factors accumulate with weight gain
1.8
1.2
0.6
0
Q1 Q2 Q3 Q4 Q5 Overall
Thin Obese
Risk variables include bottom quintile for HDL-C and top
quintiles for cholesterol, SBP, triglycerides and glucose Wilson PWF, & Kannel WB
Nutr Clin Care 1999; 1:44-50
75. Risk Assessment
Count major risk factors
• For patients with multiple (2+) risk
factors
– Perform 10-year risk assessment
• For patients with 0–1 risk factor
– 10 year risk assessment not required
– Most patients have 10-year risk <10%
87. What is WJC’s 10-year absolute
risk
of fatal/nonfatal MI?
• A 12% absolute risk is derived from points
assigned in Framingham Risk Scoring to:
– Age: 6
– TC: 3
– HDL-C: 2
– SBP: 2
– Total: 13 points
In 1992 he exercised 14 minutes in a Bruce protocol exercise
stress test to 91% of his maximum predicted heart rate without
any abnormal ECG changes. He started on a statin in 2001.
But in Sept 2004, he needed urgent coronary bypass surgery.
89. CHD Risk Equivalents
• Risk for major coronary events
equal to that in established CHD
• 10-year risk for hard CHD >20%
Hard CHD = myocardial infarction + coronary
death
90. Diabetes as a CHD Risk
Equivalent
• 10-year risk for CHD ≅ 20%
• High mortality with established CHD
– High mortality with acute MI
– High mortality post acute MI
91. CHD Risk Equivalents
• Other clinical forms of
atherosclerotic disease (peripheral
arterial disease, abdominal aortic
aneurysm, and symptomatic carotid
artery disease)
• Diabetes
• Multiple risk factors that confer a 10-
year risk for CHD >20%
93. International Comparisons in
CVD Morbidity and Mortality
• CVD accounts for 25-45% of deaths
among different countries
• CVD death rates (per 100,000)
range from 1310 in Russia to 201 in
Japan (6.5 fold difference) in men
and from 581 in Russia to 84 in
France (7-fold difference)
• USA ranks 16th for both men (413)
and women (201)
94. Secular Trends in CHD and
Stroke Mortality
• From 1985-1992, greatest annual
decline (6-7%) in CHD seen in Israel
among men and France among
women, USA intermediate (4%),
increases in Poland and Romania.
• Stroke death rates declined most in
Australia, Italy, and France (8-9%),
USA about 3%.
95. Age-Adjusted Death Rates for Coronary Heart Disease by Country and Sex,
Ages 35-74, 1999
•Age-Adjusted to European Standard
•Data for 1999 unless noted
Source: NHLBI 2002 Chart Book on Cardiovascular, Lung, and Blood Diseases
96. Age-Adjusted Death Rates for Stroke by Country and Sex, Ages 35-74, 1999
•Age-Adjusted to European Standard
•Data for 1999 unless noted
Source: NHLBI 2002 Chart Book on Cardiovascular, Lung, and Blood Diseases
97. Change in Age-Adjusted Death Rates for Coronary Heart Disease by Country and
Sex, Ages 35-74, 1990-1999
Men
Women
•Age-Adjusted to European Standard
•Latest data year note in parentheses
98. Change in Age-Adjusted Death Rates for Stroke by Country and Sex, Ages 35-74,
1990-1999
Men
Women
•Age-Adjusted to European Standard
•Latest data year note in parentheses
Source: NHLBI 2002 Chart Book on Cardiovascular, Lung, and Blood Diseases
99. Migrant Studies
• Ni-Hon-San Study showed
Japanese living in Japan to have
the lowest cholesterol levels and
lowest rates of CHD, those living in
Hawaii to have intermediate rates
for both, and those living in San
Francisco to have the highest
cholesterol levels and CHD
incidence
100. Pyramid of Risk
(Werner et al. Canadian Journal of
Cardiology 1998; 14(Suppl) B:3B-10B)
101. Approaches to Primary and
Secondary Prevention of
CVD
• Primary prevention involves prevention
of onset of disease in persons without
symptoms.
• Primordial prevention involves the
prevention of risk factors causative o the
disease, thereby reducing the likelihood
of development of the disease.
• Secondary prevention refers to the
prevention of death or recurrence of
disease in those who are already
symptomatic
102. Risk Factor Concepts in
Primary Prevention
• Nonmodifiable risk factors include age,
sexc, race, and family history of CVD,
which can identify high-risk populations
• Behavioral risk factors include sedentary
lifestyle, unhealthful diet, heavy alcohol
or cigarette consumption.
• Physiological risk factors include
hypertension, obesity, lipid problems,
and diabetes, which may be a
consequence of behavioral risk factors.
103. Population vs. High-Risk
Approach
• Risk factors, such as cholesterol or blood
pressure, have a wide bell-shaped distribution,
often with a “tail” of high values.
• The “high-risk approach” involves
identification and intensive treatment of those
at the high end of the “tail”, often at greatest
risk of CVD, reducing levels to “normal”.
• But most cases of CVD do not occur among the
highest levels of a given risk factor, and in fact,
occur among those in the “average” risk group.
• Significant reduction in the population burden
of CVD can occur only from a “population
approach” shifting the entire population
distribution to lower levels.
104. Expected Shifts in Cholesterol Distribution
from High-Risk, Population, and
Combined Approaches
105. Population and Community-
Wide CVD Risk Reduction
Approaches
• Populations with high rates of CVD are those with
Western lifestyles of high-fat diets, physical
inactivity, and tobacco use.
• Targets of a population-wide approach must be
these behaviors causative of the physiologic risk
factors or directly causative of CVD.
• Requires public health services such as
surveillance (e.g.,BFRSS), education (AHA,
NCEP), organizational partnerships (Singapore
Declaration), and legislation/policy (Anti-Tobacco
policies)
• Activities in a variety of community settings:
schools, worksites, churches, healthcare
facilities, entire communities
106. A conceptual framework for public
health practice in CVD prevention.
(From Pearson et al., J Public Health. 2001; 29:69 –78)
107. Communitywide CVD
Prevention Programs
• Stanford 3-Community Study (1972-75)
showed mass media vs. no intervention in
high-risk residents to result in 23% reduction
in CHD risk score
• North Karelia (1972-) showed public education
campaign to reduce smoking, fat
consumption, blood pressure, and cholesterol
• Stanford 5-City Project (1980-86) showed
reductions in smoking, cholesterol, BP, and
CHD risk
• Minnesota Heart Health Program (1980-88)
showed some increases in physical activity
and in women reductions in smoking
108. Materials Developed for US
Community Intervention
Trials
• Mass media, brochures and direct mail
• Events and contests
• Screenings
• Group and direct education
• School programs and worksite
interventions
• Physician and medical setting programs
• Grocery store and restaurant projects
• Church interventions
• Policies
109. Individual and High-Risk
Approaches
• Primary Prevention Guidelines (1995) and
Secondary Prevention Guidelines (Revised 2001)
released by the American Heart Association
provide advice regarding risk factor assessment,
lifestyle modification, and pharmacologic
interventions for specific risk factors
• Barriers exist in the community and healthcare
setting that prevent efficient risk reduction
• Surveys of CVD prevention-related services show
disappointing results regarding cholesterol-
lowering therapy, smoking cessation, and other
measures of risk reduction
Hinweis der Redaktion
Hospital Specialty_FINAL ATS 02/05/13 18:24
2.03
Rupture of atherosclerotic plaque and subsequent thrombosis of the vessel is responsible for the development of acute ischemic coronary syndromes. A lipid-rich core (particularly in the shoulder regions of lesions), abundance of inflammatory cells, a thin fibrous cap and dysfunctional overlying endothelium characterize plaques that are prone to rupture. Reference Weissberg PL. Eur Heart J Supplements 1999: 1 :T13 – 18.