Mortality and morbidity rates of patients older and younger than 75 years with acute myocardial infarction treated with intravenous streptokinase

The influence of patient age on mortality risk and on the incidence of serious hemorrhagic complications after treatment of acute myocardial infarction (AMI) with intravenous streptokinase (SK) and heparin was examined in 120 consecutive patients. No upper age limit was set for patient inclusion. The mortality rate increased abruptly in patients aged 75 years or older such that the 24 patients in that age group had a 10-fold higher in-hospital mortality rate (33% vs 3%) and 1-year mortality rate (42% vs 4%) than the 96 patients younger than 75 years. This increased mortality rate in the elderly patients was related to a 2-fold higher incidence of major hemorrhagic complications (24% vs 11%) and an increased incidence of anterior AMI, healed prior AMI, multiple-vessel coronary artery disease and extensive myocardial necrosis estimated by peak creatine kinase-MB. Hemorrhagic complications were more frequent in women than in men and in patients with diabetes mellitus or systemic hypertension; all of these conditions were more prevalent in patients aged 75 years and older than in those younger than 75 years. In contrast, the incidence of hemorrhagic complications in nondiabetic elderly men (1 of 12) was similar to the incidence of bleeding in the patients younger than 75 years. Based on our data and those from other studies reporting no reduction in mortality in elderly patients with AMI who are treated with intravenous SK, it is recommended that patients aged 75 years or older should not be routinely treated with intravenous SK. This recommendation appears to be especially pertient for elderly women and those with a history of diabetes mellitus or systemic hypertension. The role of intravenous SK for treatment of AMI in nondiabetic, nonhypertensive elderly men may warrant further study because our data suggest that in such patients intravenous SK is reasonably safe.