Exercise blood pressure predicts mortality from myocardial infarction

Apparently healthy men (n=1999, 40 to 59 years old) were investigated from 1972 through 1975 to determine whether systolic blood pressure during bicycle ergometer exercise predicts morbidity and mortality from myocardial infarction beyond that of casual blood pressure taken after 5 minutes of supine rest. During a follow-up of 31 984 patient-years (average, 16 years), 235 subjects had myocardial infarctions, of which 143 were nonfatal and 92 were fatal. Exercise blood pressure was more strongly related than casual blood pressure to both morbidity and mortality from myocardial infarction. Among 520 men with casual systolic blood pressure greater than or equal to 140 mm Hg, 304 increased their systolic blood pressure to greater than or equal to 200 mm Hg during 6 minutes of exercise at an initial workload of 600 kpm/min. These 304 men had an excessive risk of myocardial infarction (18.8% versus 9.5% among the 1294 men with casual blood pressure <140 mm Hg and exercise blood pressure <200 mm Hg; P<.001). As many as 58% of those with myocardial infarction in this group died, compared with 33% (range, 26% to 35%) for all other groups (P=.0011), including those with casual blood pressure greater than or equal to 140 mm Mg and exercise blood pressure <200 mm Hg. Thus, exercise blood pressure is a stronger predictor than casual blood pressure of morbidity and mortality from myocardial infarction, and an early rise in systolic blood pressure during exercise adds prognostic information about mortality from myocardial infarction among otherwise healthy middle-aged men with mildly elevated casual blood pressure. We suggest that blood pressure taken during standardized exercise testing may distinguish between severe and less severe hypertension.