Prior studies suggest that circulating n-3 and
trans-fatty acids influence the risk of
sudden cardiac arrest (SCA). Yet, while other
fatty acids also differ in their membrane properties and
biological activities which may influence SCA, little is known about the associations of other circulating
fatty acids with SCA. The aim of this study was to investigate the associations of 17 erythrocyte membrane
fatty acids with SCA risk. We used data from a population-based case-control study of SCA in the greater Seattle, Washington, area. Cases, aged 25-74 years, were out-of-hospital SCA patients, attended by paramedics (n=265). Controls, matched to cases by age, sex and calendar year, were randomly identified from the community (n=415). All participants were free of prior clinically-diagnosed
heart disease. Blood was obtained at the time of
cardiac arrest by attending paramedics (cases) or at the time of an interview (controls). Higher levels of erythrocyte very long-chain
saturated fatty acids (VLSFA) were associated with lower risk of SCA. After adjustment for risk factors and levels of n-3 and
trans-fatty acids, higher levels of 20:0 corresponding to 1 SD were associated with 30% lower SCA risk (13-43%, p=0.001). Higher levels of 22:0 and 24:0 were associated with similar lower SCA risk (
ORs for 1 SD-difference: 0.71 [95% CI: 0.57-0.88, p=0.002] for 22:0; and 0.79 [95% CI: 0.63-0.98, p=0.04] for 24:0). These novel findings support the need for investigation of
biologic effects of circulating VLSFA and their determinants.