Abstract 9238: Fatty Acids and Sudden Cardiac Death
Background: Although dietary guidelines recommend increasing N-6 polyunsaturated fat (PUFA) intake, there are concerns that N-6 PUFAs may compete with N-3 PUFA metabolism and attenuate health benefits. N-3 PUFAs have antiarrhythmic properties and intake is inversely associated with sudden cardiac death (SCD) risk. Little is known regarding the relation of N-6 PUFAs and SCD risk, despite having similar antiarrhythmic properties in experimental models. Therefore we examined the associations, and the potential interactions, of N-6 and N-3 PUFAs on SCD risk.
Methods: We followed 91,981 women from the Nurses' Health Study, age 34 to 59 in 1980. Information on diet was obtained via questionnaires every 4 years; other factors were assessed biannually. SCD was defined as death within 1 hour of symptom onset. Relative risks (RR) and 95%CI were estimated by multivariable Cox proportional hazards models.
Results: We documented 385 cases of SCD through June 2010. Total PUFAs were inversely associated with risk of SCD, and similar associations were seen for N-6 and N-3 PUFAs (Table). For N-6 PUFAs, linoleic acid, but not arachidonic acid, was associated with lower risk of SCD. For N-3 PUFAs, alpha-linolenic acid, but not marine N-3 PUFAs (eicosapentaenoic acid [EPA] + docosahexaenoic acid [DHA]), were inversely associated with risk. When modeled as a % total fat (a measure of dietary fat quality), marine N-3 PUFAs were significantly associated with lower risk (RR quintile 5 v. 1: 0.53; 95%CI: 0.37, 0.74 ). Women in the highest tertile of both N-3 and N-6 PUFA intake had the lowest risk of SCD (RR= 0.58; 95%CI: 0.40, 0.82) compared to women in the lowest tertile for both PUFAs (P, interaction=0.02).
Conclusions: Higher intake of both N-6 and N-3 PUFAs was associated with lower risk of SCD. N-6 PUFA intake enhances, rather than attenuates, the inverse association between N-3 PUFA intake and SCD. These results support the AHA dietary guidelines to increase N-6 and N-3 PUFAs intake for heart health.
- © 2011 by American Heart Association, Inc.