摘要:The hospitalization rate for acute coronary syndrome (ACS) for people aged ≤50 has remained stable over the past decade. Increased serum levels of n-3 polyunsaturated fatty acids (PUFAs), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are associated with a decreased incidence of cardiovascular events and mortality in older patients; however, it is currently unknown whether reduced serum levels of n-3 PUFAs is also a risk factor for ACS in patients aged ≤50 years. We retrospectively reviewed 102 (male/ female 73/29) Japanese ACS patients whose serum levels of EPA/arachidonic acid (AA) and DHA/AA were evaluated on admission. The EPA/AA ratio was the lowest in patients aged ≤50 compared to patients aged 51–74 and ≥75. Pearson correlation analysis showed that early ACS onset was associated with low EPA/AA and DHA/AA ratios, and multiple regression analysis determined that decreased ratios of EPA/AA and DHA/AA, and male sex, current smoker status, increased body mass index and triglyceride levels, independently correlated with early ACS onset. Conversely, low-density and high-density lipoproteins, glycated hemoglobin, and hypertension did not correlate with early ACS onset. Subgroup analyses of male patients revealed that decreased ratios of EPA/AA and DHA/AA independently correlated with early ACS onset. Decreased EPA/AA and DHA/AA ratios may be risk factors for early onset of ACS, suggesting that reduced EPA/AA and DHA/AA may represent targets for preventing ACS in Japanese young people.