My Dear Colleagues

Over the past two centuries, the industrial and technological revolutions and their associated economic and social transformation have resulted in dramatic shifts in the diseases responsible for illness and death. Cardiovascular Disease (CVD) has emerged as the dominant chronic disease in many parts of the world, and early in the 21st century it is predicted to become the main cause of disability and death worldwide. At the beginning of the 20th century, CVD accounted for less than 10 percent of all deaths worldwide. At the beginning of the 21st century CVD accounts for nearly half of all deaths in the developed world and a Quarter of all deaths in the developing world. By 2020 it is predicted that CVD will claim 25 million lives annually and Coronary Heart Disease (CHD) will surpass infectious disease as the world’s number one cause of death and disability. This global rise in CVD is the result of a dramatic shift in the health status of individuals around the world during the course of the 20th century. Before 1900, infectious disease and malnutrition were the most common causes of death. These have been gradually supplanted in some (mostly developed) countries by chronic diseases such as CVD and cancer, thanks largely to improved nutrition and public health measures. As this trend spreads to developing countries, CVD will dominate as the major cause of death by 2020, accounting for at least one in every three deaths. Continued improvements in living standards, urbanization and radical changes in the nature of work-related activities lead to dramatic life-style changes in diet, activity levels and behaviors such as smoking. Easier access to less expensive foods and increased fat content increase total caloric intake, whereas mechanization results in lower daily caloric expenditure. This disparity leads to a higher mean body mass index, Blood pressure and levels of plasma lipids and blood sugar. These changes set the stage for the emergence of hypertensive diseases and atherosclerosis. In industrialized nations, however, major technological advances such as coronary care units, bypass surgery, percutaneous coronary interventions, and thrombolytic therapy are available to manage the acute manifestations of CVD. Preventive strategies such as smoking cessation and blood pressure management are widely implemented. As a result of better treatment and widespread primary and secondary prevention efforts, deaths are prevented among people with disease and primary event are delayed. We are now halfway through a two-century transition in which CVD will dominate as the major cause of death and disease. Although CVD rates are declining in the developing countries, they are increasing in virtually every other region of the world. Each region of the world faces major challenges presented by the epidemic of CVD. There is no single global solution to the rising burden of CVD given the vast differences in social, cultural, and economic circumstances. In Iran we must find ways to efficiently care for increasing numbers of individuals with CVD as well as to deploy lowcost preventive strategies. Allocation of resources to less-expensive preventive strategies will likely be more less-expensive than dedicating resources to expensive measures.