Epidemiology of coronary heart disease- Global and Indian scenario

1. Coronary Heart Disease :
Epidemiology
Presented By
Dr Garima Gupta
MBBS , MD Post Graduate student
University College Of Medical Sciences & GTB Hospital,
Delhi
1

2. Cardio-Vascular Disease
• Cardiovascular diseases (CVDs) are a group of disorders of the
heart and blood vessels.
Coronary heart disease/
Coronary artery disease
Cerebrovascular disease
Peripheral arterial disease
Rheumatic heart disease
Congenital heart disease
Deep vein thrombosis and
pulmonary embolism.

3. Proportions of death from CVD due to coronary heart
disease, cerebrovascular disease and other CVDs in
males
Global atlas on cardiovascular disease prevention and control, World Health Organisation
11%
1%
2%
6%
34%
46%
Other CVD Rheumatic Heart Disease Inflammatory Heart Disease
Hypertensive Heart Disease Cerebrovascular Disease Coronary Heart6 Disease

4. Proportions of death from CVD due to coronary heart
disease, cerebrovascular disease and other CVDs in
females
Global atlas on cardiovascular disease prevention and control, World Health Organisation
14%
1%2%
7%
37%
39%
Other CVD Rheumatic Heart Disease Inflammatory Heart Disease
Hypertensive Heart Disease Cerebrovascular Disease Coronary Heart Disease

5. CAD-epidemiology
• Descriptive epidemiology - Describing distribution of
coronary artery disease by means of certain characteristics
such as : PERSON (i.e., age, gender, ethnicity) TIME and PLACE
• Analytical epidemiology - Analysing relationships
between CAD and risk factors (which elevate the probability
of a disease at population level), risk model and multicausal
developments
• Interventional epidemiology - Strategies of
cardiovascular prevention (primordial, primary, secondary,
tertiary; individual and community levels)

6. Coronary Artery Disease
• Enas EA. How to Beat the Heart Disease Epidemic among South Asians: A Prevention and
Management Guide for Asian Indians and their Doctors. Downers Grove: Advanced Heart Lipid
Clinic USA; 2010.
TypeI
• Young
individuals < 50
years
• Marked
prematurity ,
severity
• High prevalence
of emerging risk
factors
TypeII
• Older individuals
> 65 years
• Mild – moderate
severity
• High prevalence
of traditional
risk factors.
TypeIII
• Also known as
“MIXED
VARIETY”
• Individuals
between 50-65
years of age
• Role of both
classes of risk
factors present.

7. Descriptive Epidemiology

8. Descriptive Epidemiology :
Distribution Patterns in the World

9. Disease burden (World)
(expressed as percentage of DALYs Lost)
• World Health Organisation ( WHO) Report 2002
0.00%
1.00%
2.00%
3.00%
4.00%
5.00%
6.00%
7.00%
8.00%
9.00%
HIV/AIDS CHD Stroke UDD RTA TB COPD Hearing
loss
PERCENTAGEOFDALYSLOST
Males Females

10. India
• Indians with Coronary Artery Disease (in millions)
• * - 780 million adults > 20 years of age
• ** - 800 million adults > 20 years of age
• National Commission on Macroeconomics and Health.
• Enas EA, Mehta J. Malignant coronary artery disease in young Asian Indians: thoughts on
pathogenesis, prevention, and therapy. Coronary Artery Disease in Asian Indians (CADI)
Study. Clin Cardiol. Mar 1995;18(3):131-135.
Age 2010* 2015** Increase from
2010 to 2015 (%)
All 47.0 61.8 32
<50 yrs of age 28.4 37.3 31
<40 yrs of age 17.4 23.0 32
<30 yrs of age 8.3 10.5 27

11. Deaths due to CAD (India)
• * - 780 million adults > 20 years of age
• ** - 800 million adults > 20 years of age
• National Commission on Macroeconomics and Health.
• Enas EA, Mehta J. Malignant coronary artery disease in young Asian Indians: thoughts on
pathogenesis, prevention, and therapy. Coronary Artery Disease in Asian Indians (CADI)
Study. Clin Cardiol. Mar 1995;18(3):131-135.
Age 2010* 2015** Increase from
2010 to 2015 (%)
All 2.3 2.9 26
< 50 years of age 1.14 1.5 32
< 40 years of age 0.70 0.92 31
< 30 years of age 0.33 0.42 27

12. Deaths from coronary artery disease

13. Coronary heart disease mortality (in percentages) between
Developed Nations and Developing Nations (1990 and 2020)
44%
31%
56%
69%
0%
10%
20%
30%
40%
50%
60%
70%
80%
1990 2020
Developed nations Developing Nations

14. World trends and International Comparisons
• Cardiovascular disease (CVD) and coronary heart disease (CHD) deaths
(millions) in India, China, and established market economies (EME) from
the Global Burden of Diseases Study. (Ezzati et al., 2004)
1990 2000 2010 2020
INDIA CHIN
A
EME INDIA CHIN
A
EME INDIA CHINA EME INDI
A
CHI
NA
EME
CVD 2.26 2.57 3.18 3.01 3.30 3.49 3.80 3.81 3.53 4.77 4.53 3.66
CAD 1.18 0.76 1.67 1.59 0.99 1.84 2.03 1.15 1.87 2.58 1.37 1.95
119 % Increase

15. • EME- Established Market Economies
1.18
1.59
2.03
2.58
0.76
0.99
1.15
1.37
1.67
1.84 1.87
1.95
0
0.5
1
1.5
2
2.5
3
1990 2000 2010 2020
Deathsinmillions Deaths due to Coronary heart disease
India China EME

16. Model of the Stages of Epidemiologic
Transition
Stages of
development
Deaths
from
CVD
Predominant CVD and Risk Factor Regional Examples
Age of pestilence and
famine
5-10 %
of total
deaths
Rheumatic heart disease,
infections, and nutritional
cardiomyopathies
Sub-Saharan Africa,
rural India,
South America
Age of receding
pandemics
10-35 As above hypertensive heart
disease and hemorrhagic strokes
China
Age of degenerative
and
man-made diseases
35-65 All forms of strokes, ischemic heart
disease at young ages,
increasing obesity, and diabetes
Urban India, former
socialist
economies, aboriginal
communities
Age of delayed
degenerative
diseases
< 50 Stroke and ischemic heart disease
at old age
Western Europe,
North America,
Australia, New
Zealand
Age of health
regression and
social upheaval
35-55 Re-emergence of deaths from rheumatic
heart disease,
infections, increased alcoholism, and
violence; increase in
Russia

17. • Regression Dilution Bias
• Lag Effect

18. Economic burden
Cost
of CAD
Cost to the
individual
and family
Cost to
government
of health
care
Cost of
“HUMAN
LIFE”
Cost to
country of
lost
productivity

19. • A cross-sectional study was conducted by Huffman et al
Patients in Argentina, China, India, and Tanzania bear a
significant burden of out-of-pocket payments, as defined by
Catastrophic Health Spending and Distress Financing,
following CHD hospitalization, though substantial variations
exist across and within countries.
• A Cross-Sectional Study of the Microeconomic Impact of Cardiovascular Disease Hospitalization in Four Low- and
Middle-Income Countries

20. Descriptive Epidemiology :
Distribution Patterns as per Age and Gender
• National Health and Nutrition Examination Survey: 2009–2012.
• Mozaffarian D et al. Circulation. 2015;131:e29-e322
• American Heart association
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
20-39 40-59 60-79 80+
0.60%
6.30%
19.90%
32.20%
0.60%
5.60%
9.70%
18.80%
PERCENTOFPOPULATION
AGE IN YEARS
Prevalence of coronary heart disease by age and
gender

21. Descriptive Epidemiology :
Distribution Patterns as per Gender
• Higher rates of coronary heart disease among men compared
with women (premenopausal age)
• Heart disease affects women approximately 10 years later
than men, possibly due to the protective effect of estrogen.A
woman’s risk of a heart attack increases steeply after
menopause, when her LDL-C and triglyceride levels begin to
increase and her good cholesterol (HDL-C) level begins to fall.
• After menopause, women’s cholesterol levels are, on
average, higher than those of men of about the same age.

22. Descriptive Epidemiology :
Distribution Patterns as per Ethnicity
Prevalence of CVD for specific degrees of carotid atherosclerosis. The
prevalence of CVD increases with increasing carotid atherosclerosis in
each ethnic group.

23. • Although both Chinese and Asian Indians in the US are
classified as Asian Americans, they are diametrically opposite
in terms of morbidity and mortality from CAD (coronary
artery disease).
• Despite very high rates of smoking and high blood pressure,
the Chinese have very low and the Japanese have the lowest
rates of heart disease .
• In sharp contrast Asian Indians have the highest rates of heart
disease despite having similar or lower levels of traditional
risk factors, with the exception of diabetes

24. Asian-Indian paradox
• Asian Indian paradox refers to the excess burden of
heart disease among Asian Indians despite having a low
prevalence of traditional risk factors. Studies in the US,
UK, Canada, Singapore, and other countries have
shown prevalence of traditional risk factors such as
smoking, obesity, hypertension, and high cholesterol
levels is similar or lower in Asian Indians compared to
Europids.

25. • Coronary artery disease (CAD) rates and lipoprotein levels are
similar among vegetarians and non-vegetarians. This is in
sharp contrast to the findings from Western vegetarians, who
have a favourable lipid profile and low rates of CAD.
• Although the prevalence of insulin resistance, glucose
intolerance, metabolic syndrome, and diabetes are very high,
these conditions do not fully explain the excess burden of
premature death from CAD among Asian Indians.
• Prospective studies have shown that the incidence and
mortality from CAD is at least two-fold higher among Asian
Indians, even when adjusted for standard risk factors
including diabetes and metabolic syndrome.

26. Analytical epidemiology

27. Non Modifiable factors and Modifiable factors
Non-Modifiable factors Modifiable factors
Advancing Age High Blood Pressure
Gender Obesity
Heredity / Family history Abnormal Blood Lipids
Ethnicity / Race Unhealthy Diet
Tobacco use
Diabetes
Physical inactivity

28. Other Modifiable Risk Factors Novel Risk Factors
Socio-economic Status Excess homocysteine in blood
Alcohol Use Abnormal blood coagulation
Mental Ill health Inflammation
Psycho-social stress
Lipoprotein(a)
CRP
Vitamin - D

29. Genetics
• Recent genome wide association studies indicate that genetic
factors predisposing to heart attack in patients with heart
disease are distinct from those that associate with the
presence of heart disease.
• Having ABO blood group “O” may reduce the risk of heart
attack by up to 20%.
• Reilly M P, Li M, He J, et al. Identification of ADAMTS7 as a novel locus for coronary atherosclerosis and
association of ABO with myocardial infarction in the presence of coronary atherosclerosis: two genome-wide
association studies. Lancet. Jan 29 2011;377(9763):383-392.

30. • A study which compared 12,393 individuals with coronary
artery disease (CAD) with 7383 controls (without any
narrowing on angiography) , identified a new locus,
ADAMTS7, to be a common genetic risk factor for heart
disease, with a 19% increased risk for carriers.
• Nine genome wide studies have found 14 chromosomal loci at
which one or more common single nucleotide polymorphisms
(SNPs) are associated with CAD or heart attack. Almost all
these studies have implicated the 9p21.3 locus, considered as
the most widely and consistently replicated genetic risk factor
for CAD.
• Reilly M P, Li M, He J, et al. Identification of ADAMTS7 as a novel locus for coronary atherosclerosis and
association of ABO with myocardial infarction in the presence of coronary atherosclerosis: two genome-wide
association studies. Lancet. Jan 29 2011;377(9763):383-392.

31. Blood Pressure
• High blood pressure (hypertension) is one of the most
important preventable causes of premature death worldwide.
• Even a blood pressure at the top end of the normal range
increases risk.
• High BP is SBP >140 mmHg and/or DBP >90 mmHg
Predictor in relation to CAD /CHD
• Does the Relation of Blood Pressure to Coronary Heart Disease Risk Change With Aging? The
Framingham Heart Study
< 50 years of age DBP strong predictor
50-59 years of age SBP + DBP + PP
(Transition state)
> 60 years of age PP as best predictor

32. ROLE OF HDL-C AND LDL-C
HDL-C
< 40 mg/dl in men
< 50 mg/dl in
women
LDL-C > 100 mg/dl
Triglycerides >150
mg/dl
BALANCE OF CAD
INDEPENDENT
RISK FACTOR

33. Lipoprotein (a) “The Deadly Cholesterol”
• Lipoprotein (a) is a strong, putative, and causal risk factor for
heart disease. It is a genetic variant of LDL.
• Lp (a) is one of the strongest biological markers for premature
heart disease.
• Enas EA, Chacko V, Senthilkumar A, Puthumana N, Mohan V. Elevated lipoprotein(a)–a genetic
risk factor for premature vascular disease in people with and without standard risk factors: a
review. Dis Mon. Jan 2006;52(1):5-50.

34. Multiplicative effects of Lp(a)
• Enas EA, Chacko V, Senthilkumar A, Puthumana N, Mohan V. Elevated lipoprotein(a)–a genetic
risk factor for premature vascular disease in people with and without standard risk factors: a
review. Dis Mon. Jan 2006;52(1):5-50.
Risk outcome
Elevated levels of Lp(a) present only *3
+ low HDL-C *8
+ high LDL-C *12-14
+ high TC/ HDL-C Ratio *25
+ high homocysteine *12-30
+ other risk factors Can extend up to *122

35. Tobacco
• Tobacco causes a fifth of cardiovascular disease worldwide.
• India is the home to 12% of world’s smokers. (WHO)
• In the USA, up to 62 000 people die each year from heart
disease caused by passive smoking.
• Quitting smoking effectively reduces cardiovascular risk to
close to that of a person who has never smoked.
25 cigarettes/day – risk
by 8 times
High BP
Risk in women who
use OCP
Risk of death and re-
infarction after CABG
Beneficial effects of
physical activity
Life expectancy
INCREASE
DECREASE
EFFECT OF SMOKING TOBACCO

36. Physical inactivity
• A coalescence of anthropological estimations of Homo
sapiens’ phenotypes in the late Palaeolithic era 10,000 years
ago, with Darwinian natural selection synergized with Neel’s
idea of the so-called thrifty gene suggests that humans
inherited genes that were evolved to support a physically
active lifestyle.
• Worldwide, physical inactivity causes about 1.9 million
deaths, 20% of cardiovascular disease and 22% of coronary
heart disease.
• Being physically inactive increases your risk of coronary heart
disease and ischaemic stroke by around 1.5 times.

37. Obesity
• Abdominal girth and waist-to-hip ratio are useful indicators of
obesity.
• The Body Mass Index (BMI), a measure of weight in relation
to height, is commonly used for classifying overweight and
obesity.

38. Diabetes and CAD
DIABETICS
12-40 times the rate of CAD as
in non-diabetic
More advanced atherosclerosis
. High blood glucose is a
greater risk factor for CAD and
stroke than smoking
poor success and survival rates
following angioplasty and
bypass surgery
2 Times more mortality rate

39. Socio-economic status
In developing countries, higher socioeconomic class has been
associated with a higher prevalence of CAD.
• Coronary artery disease in the developing world - Karen Okrainec, MSc, a Devi K. Banerjee, MD,
b and Mark J. Eisenberg, MD, MPHc Montreal, Quebec, Canada
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
High SES Low SES
61%
30%
20%
9%
Prevalence of CAD in Urban Population as per
SES status
Males Females

40. Psychological
• Contrary to common belief, type A personality is not
associated with an excess of coronary artery disease
(CAD). Moreover, the prognosis of CAD among type A persons
is better than in type B patients.
• Type “D” personality: defined as the joint tendency towards
negative affectivity and social inhibition. It is associated with
coronary heart disease. [??]
• Enas EA, Garg A, Davidson MA, Nair VM, Huet BA, Yusuf S. Coronary heart disease and its risk factors in
first-generation immigrant Asian Indians to the United States of America. Indian Heart J. 1996;48(4):343-
353.

41. hs-CRP
• Acute phase reactant ( inflammatory marker)
• CRP level has been proposed as biomarker for CVD and CAD
risk prediction and as a selection marker for initiating statin
treatment.
• More than 70% of obese women and more than 50% of obese
men having elevated levels of CRP
• Smokers have 38% higher CRP levels than Non-smokers
• Ridker PM, Wilson PW, Grundy SM. Should C-reactive protein be added to metabolic syndrome and to
assessment of global cardiovascular risk? Circulation. Jun 15 2004;109(23):2818-2825.
• Jeemon P, Prabhakaran D, Ramakrishnan L, et al. Association of high sensitive C-reactive protein (hsCRP) with
established cardiovascular risk factors in the Indian population. Nutrition & metabolism. Mar 28 2011;8(1):19.

42. Vitamin-D
• Low vitamin D levels are highly associated with endothelial
dysfunction, atherosclerosis, heart attack, heart failure,
stroke as well as silent and symptomatic CAD (coronary artery
disease), CVD (cardiovascular disease) and death.
• Vitamin D concentrations are inversely associated with insulin
resistance (IR) and metabolic syndrome (MS).
• Anagnostis P, Athyros VG, Adamidou F, Florentin M, Karagiannis A. Vitamin D and cardiovascular disease: a novel agent for
reducing cardiovascular risk? Curr Vasc Pharmacol. Sep 2010;8(5):720-730
• Wang TJ, Pencina MJ, Booth SL, et al. Vitamin D deficiency and risk of cardiovascular disease. Circulation. Jan 29
2008;117(4):503-511

43. Risk assessment scores
• Framingham risk score
• Lifetime risk
• Risk estimation by disease status
• SCORE (Systematic COronary Risk Evaluation)
• German PROCAM Risk score
• Pooled cohort risk score

44. Interventional epidemiology

45. Primordial prevention
prevention of the risk factors for CVD,
such as efforts aimed to prevent
hypertension, obesity, or
dyslipidaemia
Primary prevention
modification of these and other known
risk factors, is aimed at preventing the
clinical manifestations of CVD, such as
myocardial infarction and stroke
Secondary prevention
focuses on those who already have
manifestations of disease, but where
aggressive control of risk factors can
have a major impact in preventing
recurrences of disease.
Tertiary prevention
use of expensive coronary
interventional procedures such as
coronary angioplasty, stent, bypass
surgery, pacemakers, defibrillators,
and left ventricular assist devices
(LVAD).

46. ABCDE Approach
• Oxford Textbook of Global Public Health
Aspirin / Anti-platelet therapy
Blood pressure monitoring
Cholesterol & Dyslipidaemia
management
Diet and Nutrition
Exercise and Physical Activity
A
B
C
D
E

47. Three Pronged Approach
Individual
Policies/
legislati
on
Community/
population

48. Individual level
 Take moderate physical activity for a total of 30 minutes on
most days of the week.
 Avoid tobacco use and exposure to environmental smoke;
make plans to quit if you already smoke.
 Diet: fruits, vegetables and avoid saturated fats and calorie-
dense meals.
 Maintain a normal body weight.
 Reduce stress at home and work.

50. Population / community level
• Significant health gains in cardiovascular health can be made
within short time spans, through public health and treatment
interventions that have an impact on large segments of the
population.
• Population based observational studies in Finland, Norway,
Mauritius, Poland and the US reported substantial reduction
in cholesterol levels and coronary artery disease (CAD)
mortality, following the introduction of fiscal policies which
reduced animal fat and increased vegetable fat consumption

51. FINLAND
North Karelia Project
By 2005, CAD mortality in men and women
had declined by 80%.
POLAND
Mortality due to CAD fell 40% from 1990 to
2002 (decrease of 3% per year), reversing the
previous steady rises (increase of 6% per
year)
MAURITIUS
Total cholesterol levels in the population fell
by 32 mg/dl between 1987 and 1992.This
followed an intervention by the government
in 1987, to change the composition of the
commonly used cooking oil from mostly palm
oil (high in saturated fatty acids) to soya bean
oil exclusively
NORWAY
Between 1975 and 1993 dietary saturated fat
consumption reduced by 18% of energy
intake, leading to a reduction in blood
cholesterol of 10% in the general population
and decreasing CAD mortality by 50% among
middle-aged men

52. Policies and Legislations
• Global Action Plan for the Prevention and Control
of NCDs 2013-2020
• National Programme For Prevention And Control Of Cancer,
Diabetes, CVD And Stroke (NPCDCS)

53. Recommendations to address the
CAD epidemic in the Indian
subcontinent

54. Suggested policy interventions
• Establishment of a national regulatory agency to enforce
already existing tobacco control legislation (e.g., the Tobacco
Control Act and the World Health Organization’s Framework
Convention on Tobacco Control).
• High rates of use of smoked beedies and of smokeless
tobacco (chewing tobacco and paan).
• Promote healthy dietary patterns and physical activity in
schools and workplaces.
• Identification of cultural norms that might hinder CHD
prevention efforts

55. Suggested capacity building measures
• Development of research infrastructure and training of
clinical researchers.
• Establishment of high-quality national surveillance
programmes
• Assessment of the knowledge of the CHD burden

56. Suggested research initiatives
• Generation of reliable statistics on prevalence and incidence
of CAD and its risk factors and CAD-related mortality through
the initiation of large cohort studies and trial registries.
• Randomized controlled clinical trials based in South Asian
countries to answer research questions of high relevance to
the Indian subcontinent (e.g., effectiveness of the polypill in
CHD prevention, homocysteine lowering in subjects with
vascular disease).
• Studies documenting childhood risk factors, such as obesity,
in both urban and rural settings.
• Large registries and case-control studies to document the
burden of CHD and its determinants in the Indian
subcontinent.

57. Prevention Paradox
Population at Low Risk /
Moderate Risk
High Risk
Population
Majority of cases
Minority
of cases

58. Barriers to prevention
• The physicians themselves need to be educated about the
importance of prevention and the patients should be willing
to accept and act on the advice of the physicians.
• As urbanization and globalization bring beneficial changes to
LMIC countries, it also increases the risk factors for CHD and
promotes unhealthy practices.
• The cost of preventive care is rarely reimbursed by the
government or the insurance companies like that of the
curative care.
• Enas EA, Singh V, Gupta R, Patel R, et al. Recommendations of the Second Indo-US Health Summit for the prevention and
control of cardiovascular disease among Asian Indians. Indian heart journal. 2009;61:265-74.
• Rankin J, Bhopal R. Understanding of heart disease and diabetes in a South Asian community: cross-sectional study testing
the ‘snowball’ sample method. Public Health. 2001;115(4):253-260.

59. Barriers….
• Reducing excess risk in South Asians requires multilevel,
positive, mainstream and targeted measures using multiple
approaches. These should address awareness, access,
services, discrimination, cultural sensitivity and biologic
factors, modified for different countries, situations and
contexts.
• The Indo-US Healthcare Summit provides comprehensive,
detailed and practical recommendations, advocating
primordial, primary, and secondary prevention by
government, medical communities, the public, industry and
the media.
• Policy, grass-roots change, and community building should
encourage healthy living at all ages, and remove barriers.
Population screening, awareness and change should start
early and tap community strengths.

60. Future
• Predictions are by their nature speculative. Nevertheless, this
much is certain: the global epidemic of cardiovascular disease
is not only increasing, but also shifting from developed to
developing nations.
• No matter what advances there are in high-technology
medicine, the fundamental message is that any major
reduction in deaths and disability from CAD will come from
prevention, not cure. This must involve robust reduction of
risk factor

61. • “Live sensibly - among a thousand people,
only one dies a natural death; the rest
succumb to irrational modes of living.”
- Maimonides

62. Thank You

63. Objectives of NPCDCS
• 1) Prevent and control common NCDs through behaviour and
life style changes,
• 2) Provide early diagnosis and management of common NCDs,
• 3) Build capacity at various levels of health care for
prevention, diagnosis and treatment
• of common NCDs,
• 4) Train human resource within the public health setup viz
doctors, paramedics and
• nursing staff to cope with the increasing burden of NCDs, and
• 5) Establish and develop capacity for palliative &
rehabilitative care.

64. Strategies
• The Strategies to achieve above objectives are as follows:
• 1) Prevention through behaviour change
• 2) Early Diagnosis
• 3) Treatment
• 4) Capacity building of human resource
• 5) Surveillance, Monitoring & Evaluation