INTER-HEART: A global study of risk factors for acute myocardial infarction

Background Although declines in mortality rates have occurred in most devel oped countries, increases are being seen in developing countries. Our knowl edge of risk factors for acute myocardial infarction (AMI) is largely deriv ed from studies in the former. Applicability of these results to ether popu lations is unknown. The objectives of INTER-HEART are to determine the asso ciation between risk factors and AMI within populations defined by ethnicit y and/or geographic region and to assess the relative importance of risk fa ctors across these populations. Methods INTER-HEART is a study of 14,000 cases of AMI and 16,000 matched co ntrol patients from 46 countries, which was conducted with a standardized p rotocol. Questionnaires were translated into 11 languages; physical measure ments were obtained, and 20 mL of blood was drawn and shipped frozen to a c entral laboratory in Canada. The study will evaluate the importance of conv entional and emerging risk factors within each geographic region and whethe r their impact varies by region. Results INTER-HEART is sponsored by the World Health Organization and the W orld Heart Federation and has received funding from several peer-reviewed a gencies and many different pharmaceutical companies. A vanguard phase (Febr uary 1999 to 2000) enrolled 4000 subjects from 41 countries. Full data coll ection started in April 2000 and is expected to be completed by October 200 2. Conclusions several years of targeted work have allowed the development of the concepts that were tested in the pilot studies. This has ensured the fe asibility of INTER-HEART This study has the potential to have a major impac t in developing a worldwide strategy for cardiovascular disease prevention, especially in developing countries and nonwhite populations.