Intakes of omega-3 fatty acids and risks of all-cause and cause-specific mortality in people with diabetes: a cohort study based on NHANES 1999-2014

Aims Intake of omega-3 fatty acids is associated with several health benefits, but the specific benefits in populations with diabetes have yet to be elucidated. Therefore, this study aimed to explore the relationship between intake of omega-3 fatty acids and mortality in people with diabetes. Methods This was a prospective cohort study and included 4854 participants with diabetes (mean age, 57.92 years; 50.9% male) from the National Health and Nutrition Examination Survey (1999-2014). Eicosapentaenoic (EPA) and docosahexaenoic (DHA) acid intake were used as alternative markers of omega-3 fatty acids intake and calculated based on the sum of the 24-h dietary recall interviews and dietary supplements. Mortality data were ascertained by linkage to National Death Index records by December 31, 2015. Cox proportional hazard models and restricted cubic spline were used to assess the relationship between EPA and DHA intake and all-cause and cause-specific mortality. Statistical analyses were performed using R 4.2.0 software. Results Compared with participants with a lower EPA + DHA intake, participants who had a higher EPA + DHA intake tended to be Non-Hispanic Black; were more likely to be obese; and had higher daily energy intake and family income. During 34,386 person-years of follow-up, 1102 deaths were documented, including 266 cardiovascular disease deaths and 152 cancer deaths. In multivariable regression analyses with adjustment of confounding factors, higher EPA + DHA intake was significantly and linearly related to lower all-cause mortality: there was a 25% reduced risk of all-cause mortality. Conclusions Higher omega-3 fatty acid intake was independently related to lower all-cause mortality in individuals with diabetes, suggesting an adequate intake of omega-3 fatty acids may prevent premature death among the population with diabetes.