Download PANDEMIC OF CARDIOVASCULAR DISEASE

PANDEMIC OF CARDIOVASCULAR DISEASE
A CHALLENGE AND AN OPPORTUNITY
(Prof. Shahryar A. Sheikh)
By the beginning of the of the 20th century nutritional diseases, infectious diseases and
maternal diseases accounted for a major cause of death, cardiovascular disease accounted
for only 10% of all deaths. Rheumatic Heart Disease, infectious and nutritional
cardiomyopathies made up for most of the cardiovascular disease burden.
In 1999 World Health Organization (WHO) health report indicated that world wide
Cardiovascular Disease (CVD), of which coronary artery disease and stroke are major
component caused the deaths of approximately 16.7 millions people of all ages, (8
million men & 8.7 million women).
In developed countries despite significant decline since 1970, CVD remains the leading
cause of death accounting for over five millions deaths in 1990. In the developing
countries with low and middle income, there is growing burden of CVD and in 1998
WHO estimated that 85% burden of CVD arose from the low and middle income
countries, adding to the existing burden of infectious and rheumatic heart disease.
Fortunately much is now known about the causes of common CVDs. Furthermore, the
effects of the many cardiovascular risk factors have been shown to be potentially
reversible.
The various risk factors for CVD are approximately multiplicative in their effect on CVD
risk. Therefore, the benefit will be greatest when there is a simultaneous reduction in
several risk factors.
It is important to remember that CAD is not just a Lipid disease, half of all myocardial
Infarctions occur in Normo Lipidemic patients.
Smoking accounts for 4.5 million cardiovascular deaths. Smoking increases the risk of
dying from Coronary Heart Disease and cerebrovascular disease 2-3 fold and continuing
to smoke after myocardial Infarction or coronary revascularization can have deleterious
clinical consequences. Smoking cessation is the most cost effective intervention for
patients with documented CVDs.
Diabetes affects 135 million in the world. Number of people with diabetes are projected
to increase 42% in developed countries and 170% in developing countries by 2025.
Diabetes is now recognized as a vascular disease, due to the fact that two-thirds of people
with diabetes-mellitus die from cardiovascular disease, and 75% of diabetic patients
hospitalizations are for CVD.
Hypertension confer as much risk for Myocardial Infarction as smoking or dyslipidemia.
Systolic hypertension is an even greater indicator of CAD risk than diastolic
hypertension.
One billion people across the world are now over weight or obese, leading to fears, that
obesity will rapidly overtake smoking tobacco as the leading life style risk factor for heart
disease and stroke; due to the fact that obesity predisposes to diabetes mellitus, high
blood pressure and dyslipidemia, major risk factors for CAD. Women with a body mass
index of greater than 27 have a threefold risk of stroke compared to slender women,
(BMI under 22).
The past 25 years has seen the Aspirin, -Blockers, ACE-inhibitors, and lipid-lowering
therapies to lower the risk of future vascular events, by about a quarter each, in high-risk
patients. The benefits of each intervention appear to be largely independent so that when
used together in appropriate patients it is reasonable to expect that about two-thirds to
three quarters of future vascular events could be prevented. Add to this the potential
benefits of quitting in smokers (which lowers the risk of myocardial infarction by a half)
and blood pressure lowering (a 10mmHg reduction in systolic blood pressure could
reduce the risk of cardiovascular events by a quarter) in hypertensive patients, and it may
be possible to lower the risk of future events by more than four-fifths in high risk
individuals.
Ischemic Heart Disease and stroke mortality rates have declined up to 50% in developed
countries, suggesting that the available preventive and therapeutic strategies can be
effective. WHO Monica project in Finland has shown that by reducing the classic risk
factors for CVD like smoking, Blood Cholesterol and Blood Pressure can result in almost
50% reeducation in mortality in CVD both in men and women. USA has seen one of the
greatest declines in CVD mortality rates over the last three decades. Therapeutic
advances and preventive measures, targeted at those with CVD and those potentially at
risk for it, have been attributed to the decline in CVD mortality rates.
The potential gains from the combination of currently known preventive strategies are
large. While prescription is simple implementation is much more difficult.
EUROASPIRE II showed that too many patients are not receiving adequate preventive
and therapeutic intervention as a consequence most of the patients are not achieving the
recommended goals. Cardiovascular specialist has to play an important role in CVD
control efforts alongwith enlightened policymaking and effective community
involvement.
The epidemic of cardiovascular disease in developed countries peaked at a point when
the knowledge of CVD causation and prevention was inadequate. It is a challenge for us
at present to apply this existing knowledge about CVD in developing world to avoid huge
burden of CVD in young and middle aged adults.
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