Increasing burden of cardiovascular disease: current knowledge and future directions for research on risk factors.

Lewis A. Conner was the first president of the American Heart Association and founding editor of the American Heart Journal. In the inaugural issue of that journal, in October 1925, Dr Conner wrote that the “newly awakened interest in disorders of the cardiovascular system” has rapidly led to the recognition of heart disease as a significant public health problem that “can no longer be disregarded.” In the ensuing years, the United States first experienced a 40-year increasing epidemic of cardiovascular disease, followed by remarkable gains in prevention and treatment that led to a dramatic 30-year decline in mortality from coronary heart disease (CHD) and stroke. At present, however, heart disease remains far and away the leading cause of mortality in the United States, responsible for about one of every three deaths. Stroke accounts for 6% to 7% of all deaths, so overall cardiovascular disease remains responsible for about 40% of all US deaths. Further gains in the prevention and treatment of cardiovascular disease will require concerted efforts—and the necessary allocation of resources—on at least two major fronts. First, public policy and health efforts must vigorously promote those measures in prevention and treatment for which abundant evidence of clear benefits already exists. Second, funding must be provided for current research to evaluate new possible preventive and therapeutic interventions and to expand frontiers in genetic, thrombotic, atherogenic, and inflammatory markers of cardiovascular disease risk. Advances in knowledge proceed on several fronts, optimally simultaneously. Basic researchers provide biological mechanisms and answer the crucial question of why an agent or intervention reduces premature death. Clinicians are providing enormous benefits to affected patients through advances in diagnosis and treatment and formulate hypotheses from their clinical experiences in case reports and case series. Clinical investigators address the relevance of basic research findings to affected patients and healthy individuals. Epidemiologists and statisticians, optimally collaborating with researchers in other disciplines, formulate hypotheses from descriptive studies and test these in analytical studies, both observational case-control and cohort as well as, where necessary, randomized trials. This strategy answers the equally crucial and complementary question of whether an agent or intervention reduces premature death. Thus, each discipline and indeed every strategy within a discipline provide importantly relevant and complementary information to a totality of evidence on which rational clinical decisions for individuals and policy decisions for the health of the general public can be safely based. This article reviews the increasing burden of cardiovascular disease, contributions of different types of evidence, and direction of current and future research on risk factors.