Background/Aims: Analysis of the Sydney Heart Study reported an adverse effect of dietary n-6 polyunsaturated fatty acids (PUFA) on mortality, and recent meta-analyses have reached contrasting conclusions regarding the effect of dietary n-6 polyunsaturated fatty acids (PUFA) on cardiovascular mortality. The aim of this study was to examine the effect of n-6 PUFA on mortality in the Australian Diabetes, Obesity and Lifestyle Study (AusDiab) cohort, a large Australian prospective study of cardio-metabolic health.
Methods: The relationship between dietary PUFA intake and all-cause or CVD mortality in the AusDiab cohort, a population of 11,247 Australians aged ≥25y recruited in 1999/2000 and followed until 2012, was examined using Cox regression. Comorbidities, demographic, and lifestyle information was collected by questionnaire, and fasting blood tests undertaken. Baseline dietary intake was assessed by a 121-item food frequency questionnaire. Vital status and causes of death were collected by linkage to death registries.
Results: Adjusted for age and sex, those in the highest quintile of n-6 PUFA intake had lower risk of total and cardiovascular mortality (all-cause mortality HR: 0.82, 95% CI: 0.69-0.99, p <0.05), but this failed to retain significance after further adjustment for previous cardiovascular disease, education, exercise, diabetes, dietary energy and smoking.
Conclusion: These findings from a contemporary Australian cohort suggest that n-6 PUFA have neutral or possibly beneficial effects on all-cause and cardiovascular mortality.
Funding sources: None to declare for these analyses. However AusDiab has been funded by NHMRC, as well as support from State governments, academic and industry bodies.