Serum eicosapentaenoic acid/arachidonic acid ratio is low in patients with pulmonary thromboembolism.

Recently n-3 polyunsaturated fatty acids (PUFAs) have been reported to play protective roles against cardiovascular diseases. Pulmonary thromboembolism (PTE) is one of the critical diseases in the circulatory system. However the relationship between n-3 PUFAs and PTE has not been reported. A total of 144 outpatients of the division of cardiology, including 12 of PTE cases, were enrolled in the present study and serum levels of eicosapentaenoic acid (EPA) and arachidonic acid (AA) were analyzed. We found that the EPA/AA ratio of the patients with PTE (the PTE group) was significantly lower than that of the patients without PTE (the non-PTE group) (p=0.007 for log EPA/log AA ratio). Next, the PTE group was divided into two groups by the presence or absence of malignant carcinoma. The PTE without carcinoma group showed significantly lower EPA/AA ratio than that of the non-PTE group (p=0.002 for log EPA/log AA ratio). However, the PTE with carcinoma group did not show the statistical difference in EPA/AA ratio compared with the non-PTE group (p=0.39). These data indicate that PTE may be associated with a low EPA/AA ratio, although the presence of malignant carcinoma should be taken into account.