International Task Force for Prevention of Coronary Heart Disease

International Task Force for Prevention of
Coronary Heart Disease

CORONARY HEART DISEASE: REDUCING THE RISK

In adult men the incidence of CHD rises steeply with advancing age, until about 60 years of age. A similar trend is seen in women, starting at about age 50. The impact of all risk factors is therefore substantially greater in middle-aged and elderly persons than in younger adults; this must be taken into account when CHD risk is assessed clinically, and it must be built into quantitative estimation of risk using the PROCAM-based Risk Calculator. Also, the incidence of many risk factors, including hypertension, hyperlipidaemia and diabetes, increases with age.

On the other hand, coronary atherosclerosis can and often does commence early in life, and this is accellerated in the presence of risk factors. Hence correctable risk factors need to be prevented, or detected and treated, in all age groups.

Risk factors operate at all ages; coronary disease is most common after the age of 60, and risk factor reduction is appropriate and necessary at all ages except when life expectancy is severely limited. Above about 75 years of age, low cholesterol levels are often a sign of underlying chronic illness and are associated with reduced life expectancy. One study which corrected for markers of poor health, however, found that even in persons above 80 years of age, the risk of death from coronary heart disease correlated with the serum cholesterol levels ⁷.
Genetic hyperlipidaemias require early diagnosis since coronary disease may develop before the age of 40.

2.1.2 Sex

In men, risk increases progressively with age.
In premenopausal women coronary disease is rare in the absence of diabetes mellitus or severe genetic hyperlipidaemias such as familial hypercholesterolaemia. After the menopause, risk increases progressively and approaches male risk in the age group of 70-79 years old. In absolute terms, more women than men die of coronary heart disease because of the greater life expectancy of women.

2.1.3 Physical activity and diet

Lifestyle factors, in particular diet and level of physical activity, are important determinants of coronary risk. Lack of exercise increases the risk of CHD, irrespective of other risk factors and the physician should therefore briefly assess the patient's level of physical activity at work and in leisure time. In addition, assessment of diet is part of a comprehensive patient assessment.

2.1.4 Personal history of atherosclerotic disease

One of the most powerful predictors of risk of an acute coronary event (fatal or nonfatal MI, sudden cardiac death) is the presence of objective evidence of pre-existing ischaemic heart disease (myocardial infarction or angina pectoris, ST-segment depression on exercise ECG, angiographic evidence of coronary atherosclerosis, history of myocardial infarction, unequivocal evidence of ischaemic changes in the resting ECG). This increases risk several-fold compared to persons with similar cholesterol levels but without coronary heart disease.

A high risk of CHD is also present in patients with definite peripheral vascular disease or with a history of stroke or transient ischaemic attacks.

2.1.5 Family history of CHD

A family history of coronary heart disease or peripheral vascular disease is highly informative regarding the degree of risk. The physician takes into account the number of relatives about whom reliable information exists, and notes:

how early in life vascular problems presented. Events presenting after about age 60 years are ignored,
how close the relationships are (e.g. CHD in a sibling or parent is more significant than in an uncle or cousin),
what proportion of relatives were affected. CHD in relatives who smoked heavily is discounted as being less likely to indicate genetic predispositon.

There may in addition be a family history of genetic hyperlipidaemia (in particular familial hypercholesterolaemia which has a prevalence of about 1 in 500). Such disorders require early diagnosis since coronary disease often develops before the age of 40 years, and even before age 30 years.

2.1.6 Cigarette smoking

Note the amount and duration of this independent risk factor. Recent evidence suggests that use of other tobacco products such as cigars or pipe tobacco also confers increased risk of cardiovascular disease. Smoking may be an even more important source of risk in areas with a rising incidence of cardiovascular disease, such as Asia and Eastern and Central Europe, than it is in Western Europe and North America.