EPIDEMIOLOGY OF CARDIOVASCULAR-DISEASE IN DEVELOPING-COUNTRIES

As infection and malnutrition are steadily overcome in the developing world, cardiovascular diseases loom large in the profile of morbidity and mortality in these societies. Hypertension, rheumatic heart disease and the cardiomyopathies are already taking their toll and atherosclerosis is certain to pose public health problems soon unless steps are taken now, through attention to known risk factors, to pre-empt or at least minimize its consequences. There are populations in developing countries among whom blood pressure does not appear to rise with age and in whom the prevalence of hypertension is very low. Studies of these communities and of migrant groups indicate that salt has an important effect on blood pressure. In spite of these observations, however, it is well known that black communities tend, on the whole, to show a higher prevalence of hypertension and more severe target-organ damage than white communities. Other distinguishing features are lower cholesterol, triglyceride and low-density lipoprotein fractions and a delayed response to a sodium load in black populations. Economic constraints limit the effective application of stepped-care therapy in the management of moderate to severe hypertension. Beta-blockers and angiotensin converting enzyme (ACE) inhibitors are not so effective in black communities unless combined with diuretics.