Myocardial infarction was confirmed by study physicians blinded to participant's exposure status if it met the World Health Organization's criteria (symptoms plus either diagnostic electrocardiographic changes or elevated levels of cardiac enzymes).[28], [29] Deaths were identified from state vital records and the National Death Index or reported by the participant's next of kin or the postal system. Fatal coronary heart disease was confirmed by hospital records or on autopsy, or if coronary heart disease was listed as the cause of death on the death certificate, if it was the underlying and most plausible cause, and if evidence of previous coronary heart disease was available. Among women, 80.3% of the cases were nonfatal MI, and 19.7% were fatal CHD. Among men, 73.7% of the cases were nonfatal MI, and 26.3% were fatal CHD.
