Differential Associations of Dietary Inflammatory Index and Dietary Antioxidant Indices With Mortality Risk From MASLD/MetALD: Results From a Large Population‐Based Study

Abstract

ABSTRACT Metabolic dysfunction‐associated steatotic liver disease (MASLD) and its subtype, metabolic dysfunction and alcohol‐associated liver disease (MetALD), represent escalating global health challenges. Despite the central role of dietary intervention in current guidelines, evidence remains limited regarding the synergistic impact of anti‐inflammatory and antioxidant diets on the survival benefits of steatotic liver disease (SLD) populations, particularly those with moderate alcohol consumption. This study aims to elucidate the associations between dietary inflammatory/antioxidant quality and mortality across SLD subtypes, and provide insights into dietary recommendations for this patient group. Data from 3048 individuals (2146 MASLD, 902 MetALD) who participated in the 2005–2018 National Health and Nutrition Examination Survey were analyzed. Weighted Cox regression analysis was used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) for mortality risk assessment. The mediation effects of inflammation‐related indicators were explored by mediation analysis. During the follow‐up period, a total of 306 deaths were documented. In MASLD patients, higher DII (T3) correlated with increased all‐cause mortality (HR = 1.97, 95% CI: 1.12–3.47, p = 0.019). Both CDAI and DAQS showed negative associations, with HRs of 0.50 (0.28–0.89) and 0.47 (0.24–0.93) for T3, respectively (both p < 0.05). In MetALD patients, higher DII was associated with increased mortality risk (T2 HR = 4.95, T3 HR = 3.91, both p < 0.05). Joint analysis suggested that higher dietary antioxidant quality was associated with lower mortality risks across SLD subtypes compared with the MASLD group with low dietary antioxidant quality. Mediation analysis suggested that inflammation‐related markers (platelets and PHR) may be involved in the associations between dietary indices and mortality in MASLD patients, whereas no statistically significant mediation effects were observed in the MetALD subgroup. Our findings show the key role of dietary quality in reducing mortality among patients with SLD, suggesting that anti‐inflammatory and antioxidant‐rich diets can improve long‐term survival across the SLD spectrum. The findings of this study are expected to provide a new perspective on dietary interventions as a complement to current international guidelines for MASLD/MetALD.