Dr. M. N.Tabassum M,B:B,S (Pb), D.T.C.D(Pb)

M.C.P.S (Pak ),M.P.H

Department of community MedicineKing Edward Medical University

Lahore

EPIDEMIOLOGY OF CARDIOVASCULAR

DISEASES

EPIDEMIOLOGYThe study of the distribution and

determinants of health related states and events in specified population and application of this study to control the health problems

INCIDENCE

The rate of occurrence of new cases in a defined population in a certain period of time.

PREVALENCEThe prevalence of a health-related

state in a statistical population is defined as the total number of cases of the risk factor in the population at a given time, or the total number of cases in the population, divided by the number of individuals in the population. It is used as an estimate of how common a disease is within a population over a certain period of time.

Risk factorsA risk factor is any attribute,

characteristic or exposure of an individual that increases the likelihood of developing a disease or injury. Some examples of the more important risk factors are obesity, high blood pressure, tobacco and alcohol consumption and unsafe water, sanitation and hygiene.

Cardiovascular Diseases

“An impairment of heart function due to inadequate blood flow to heart compared

to its need, caused by obstructive changes in the coronary circulation to the

heart” .

Presentation of CV diseases

1. Angina Pectoris2. Myocardial Infarction3. Irregularities Of Heart 4. Cardiac Failure 5. Sudden Death

Epidemiology of Cardiovascular Disease

In recent years, the dominance of chronic diseases as major contributors to total global mortality has emerged. By 2008, the total number of cardiovascular disease deaths (mainly coronary heart disease, stroke, and rheumatic heart disease) had increased globally to 17.5 million from 14.4 million in 1990. Of these, 7.6 million were attributed to coronary heart disease and 5.7 million to stroke.

More than 80 percent of the deaths occurred in low and middle income countries (WHO, 2009e). The World Health Organization (WHO) estimates there will be about 20 million CVD deaths in 2015, accounting for 30 percent of all deaths worldwide (WHO, 2005). By 2030, researchers project that non-communicable diseases will account for more than three-quarters of deaths worldwide and 23 million people will die annually from CVDs.

CVD alone will be responsible for more deaths in low income countries than infectious diseases (including HIV/AIDS, tuberculosis, and malaria), maternal and perinatal conditions, and nutritional disorders combined Thus, CVD is today the largest single contributor to global mortality and will continue to dominate mortality trends in the future (WHO, 2009e). In Pakistan, Cardiovascular disease cause over 100,000 deaths in a year.

Cardiovascular risk factors Two groups of risk factors

A. Modifiable risk factors

B. Non-modifiable risk factors   

Modifiable risk factors

Hypertension

Is the single biggest risk factor for CVD and stroke. It also plays a significant role in heart attacks. It can be prevented and successfully treated but only if you have it diagnosed and stick to your recommended management plan.

Abnormal blood lipid levels

that is high total cholesterol, high levels of triglycerides, high levels of low-density lipoprotein or low levels of high-density lipoprotein (HDL)

cholesterol all increase the risk of heart disease and stroke. Changing to a healthy diet, exercise and medication can modify blood lipid profile.

Tobacco use whether it is smoking or chewing tobacco, increases risks of cardiovascular disease.  The risk is especially high if you started smoking when young, smoke heavily or are a woman. Passive smoking is also a risk factor for cardiovascular disease.  Stopping tobacco use can reduce your risk of cardiovascular disease significantly, no matter how long you have smoked.

Physical Inactivity

increases the risk of heart disease and stroke by 50%.  Obesity is a major risk for cardiovascular disease and predisposes you to diabetes.

Diabetes Mellitus Type2 diabetes: a major risk factor for coronary heart disease and stroke. Having diabetes makes you twice as likely as someone who does not to develop cardiovascular disease.

Diet In High Saturated Fat

Diet high in saturated fat increases the risk of heart disease and stroke.  It is estimated to cause about 31% of coronary heart disease and 11% of stroke worldwide.

Poverty/Social Factors

Being poor, no matter where in the globe, increases your risk of heart disease and stroke. A chronically stressful life, social isolation, anxiety and depression increase the risk of heart disease and stroke.

Alcohol Intake

Having one to two alcohol drinks a day may lead to a 30% reduction in heart disease, but above this level alcohol consumption will damage the heart muscle.

Medication

Certain medicines may increase the risk of heart disease such as the contraceptive pill and hormone replacement therapy (HRT).

Left ventricular hypertrophy

Left ventricular hypertrophy (LVH) is a risk factor for cardiovascular

mortality

Non-Modifiable risk factors

Old Age

Simply getting old is a risk factor for cardiovascular disease; risk of stroke doubles every decade after age 55.

Family’s History

Your family’s history of cardiovascular disease indicates your risk. If a first-degree blood relative has had coronary heart disease or stroke before the age of 55 years (for a male relative) or 65 years (for a female relative) your risk increases.

Gender

Your gender is significant: as a man you are at greater risk of heart disease than a pre-menopausal woman.  But once past the menopause, a woman’s risk is similar to a man’s. Risk of stroke is similar for men and women.

Ethnicity

Your ethnic origin plays a role.  People with African or Asian ancestry are at higher risks of developing cardiovascular disease than other racial groups.

Genetic Factors And Personality

key words:epidemiology, Cardiovascular diseases, prevalence,incidence,risk factors,obesity, hypertension,modifiable, non-modifiable ,stroke, mortality ,left ventricular hypertrophy.