Acute myocardial infarction in young and very old Chinese adults: clinical characteristics and therapeutic implications

To characterize acute myocardial infarction (AMI) in young adults and octogenarians, 475 AMI patients, in age subsets, were examined. The clinical features, risk factors and in-hospital mortality were compared among 17 young patients (<40 years), 426 patients of common age (40-79 years), and 32 very elderly patients (≥80 years). The octogenarian patients were mainly female (male/female ratio, 0.9 vs. 4.7 in other subgroups, P < 0.005), and had more frequent atypical presentation and postinfarctional congestive heart failure; whereas infarct size, location and development of Q-wave, major arrhythmias and cardiac wall rupture were not different among these age subsets. The most common risk factors in the young group were dyslipidemia (67%) and cigarette smoking (65%), and in the octogenarian group were dyslipidemia (52%) and hypertension (50%). Among age subsets, however, the prevalence of risk factors was not significantly different except for a relatively lower smoking rate in the octogenarians. Compared with 40- to 79-year-old patients who had predominantly multi-vessel diseases, the young patients had milder coronary atherosclerosis and were more likely to have normal coronaries (27% vs. 5%, P < 0.01). Significantly more octogenarians than young patients succumbed to AMI in the hospital (44% vs. 18%, P < 0.005), usually because of a cardiogenic complication (93%). Also, the octogenarians were less likely than the younger patients to have received thrombolytic therapy, mostly because of delayed diagnosis and arrival at the hospital, or because of old age itself. The conclusion was that the octogenarian AMI patients comprise a high-mortality group who may benefit potentially from thrombolytic therapy, and should not be deprived of it because of old age alone.