Dietary folate intake and all-cause mortality and cardiovascular mortality in American adults with non-alcoholic fatty liver disease: Data from NHANES 2003 to 2018.

Background: The relationship between dietary folate intake and prior mortality in adult patients with Non-alcoholic Fatty Liver Disease (NAFLD) has not been clearly studied. We aimed to examine the relationship between dietary folate intake and all-cause and cardiovascular (CVD) mortality in adult NAFLD patients in the US.

Methods: Using data from National Health and Nutrition Examination Survey (NHANES) 2003-2018 and associated mortality data we conducted a cohort study of US adult NAFLD subjects. Multivariable Cox proportional hazards regression models were used to evaluate the relationship between dietary folate intake and both all-cause mortality and CVD mortality, accounting for potential confounders. The study employed restricted cubic spline analysis to investigate the non-linear association between dietary folate levels and mortality from all causes and cardiovascular disease.

Results: Our final cohort consisted of 3,266 NAFLD patients, with a median follow-up of 10.3 years, 691 deaths were observed, including 221 cardiovascular deaths. Compared to participants with a folate intake in Quartile 1 (≤250 μg/d), those in Quartile 4 (≥467.5 μg/d) had multivariable-adjusted hazard ratios of 0.69 (95% CI, 0.51-0.94) for all-cause mortality (p for trend = 0.028) and 0.55 (95% CI, 0.29-1.04) for CVD mortality (p for trend = 0.107). A non-linear relationship between dietary intake and risk of death was not observed.

Conclusion: Greater dietary folate intake is associated with a reduced risk of all-cause in American adults with NAFLD. Higher dietary folate intake not found to be associated with lower CVD mortality. These findings suggest that dietary folate may improve the prognosis of adult NAFLD patients. The measured-response relationship between dietary folate intake and mortality in patients with NAFLD requires further investigation.