Dietary and genetic determinants of non-alcoholic fatty liver disease in coronary heart disease patients

Purpose: A healthy diet reduces the risk of non-alcoholic fatty liver disease (NAFLD) in the general population, especially in individuals who are genetically predisposed to NAFLD. Little is known in patients who suffered from a myocardial infarction (MI). We examined the interaction between diet quality and genetic predisposition in relation to NAFLD in post-MI patients. Methods: We included 3437 post-MI patients from the Alpha Omega Cohort. Diet quality was assessed with adherence to the Dutch Healthy Diet index 2015 (DHD15-index). A weighted genetic risk score (GRS) for NAFLD was computed using 39 genetic variants. NAFLD prevalence was predicted using the Fatty Liver Index. Prevalence ratios (PR) with 95% confidence intervals of DHD15-index and GRS in relation to NAFLD were obtained with multivariable Cox proportional hazards models. The interaction between DHD15-index and GRS in relation to NAFLD was assessed on an additive and multiplicative scale. Results: Patients had a mean age of 69 (± 5.5) years, 77% was male and 20% had diabetes. The DHD15-index ranged from 28 to 120 with a mean of 73. Patients with higher diet quality were less likely to suffer from NAFLD, with a PR of 0.76 (0.62, 0.92) for the upper vs lower quintile of DHD15-index. No association between the GRS and NAFLD prevalence was found (PR of 0.92 [0.76, 1.11]). No statistically significant interaction between the DHD15-index and GRS was observed. Conclusion: In Dutch post-MI patients, adherence to the Dutch dietary guidelines was associated with a lower prevalence of NAFLD, as assessed by the FLI. This association was present regardless of genetic predisposition in this older aged cohort.