Comparison of Clinical Characteristics of Acute Myocardial Infarction Between Young (< 55 Years) and Older (55 to < 70 Years) Patients.

Although the incidence of acute myocardial infarction (AMI) has been decreasing in the elderly, it has been increasing in the young, especially in Japan. A social impact of AMI would be greater in the young, because loss of the young directly influences social activities such as business, child-raising, and tax payment. The aim of this study was to identify the specific characteristics of young AMI patients. We retrospectively included 408 consecutive AMI patients < 70 years of age, divided into a young group (< 55 years: n = 136) and an older group (55 to < 70 years: n = 272). The prevalence of overweight was greater in the young group (58.5%) than in the older group (40.7%) (P = 0.001). The frequency of current smokers was higher in the young group (67.6%) than in the older group (44.9%) (P < 0.001). Although the prevalence of hypertension was lower in the young group (66.7%) than in the older group (77.2%) (P = 0.017), that of untreated hypertension was greater in the young group (40.4%) than in the older group (27.2%) (P = 0.007). Furthermore, the prevalence of untreated dyslipidemia was greater in the young group (45.0%) than in the older group (26.6%) (P < 0.001). In conclusion, the young AMI patients had more modifiable risk factors such as obesity, smoking, untreated hypertension, and untreated dyslipidemia than the older patients. There is an unmet medical need for the prevention of AMI in the young generation.