(P14-057-23) Plant-Based Diets, Genetic Predisposition, and Risk of Non-Alcoholic Fatty Liver Disease

Objectives: To prospectively examine associations of plant-based diets and genetic susceptibility with NAFLD risk.

Methods: This prospective cohort study included 159,222 participants (58.0 ± 8.0 years old, 55.7% female) free of NAFLD in the UK Biobank. We calculated the overall plant-based diet index (PDI), the healthful plant-based diet index (hPDI), and the unhealthful plant-based diet index (uPDI). Liver fat content was measured in 20,692 participants (57.5 ± 7.4 years old, 52.6% female) by magnetic resonance imaging-derived proton density fat fraction (MRI-PDFF). The weighted polygenic risk score was calculated based on risk variants associated with NAFLD. Hazard ratios (HR) and 95% confidential intervals (CI) were estimated by Cox proportional hazards model.

Results: During a median follow-up of 9.5 years, 1,541 new-onset NAFLD cases were documented. Compared to the lowest quintile, multivariable-adjusted hazard ratios (HRs) of NAFLD in the highest quintile were 0.78 (95% confidential intervals [CI], 0.66–0.93, p-trend =0.02), 0.74 (95% CI, 0.62–0.87, p-trend < 0.0001), and 1.24 (95% CI, 1.05–1.46, p-trend =0.02) for overall PDI, hPDI, and uPDI, respectively. We observed inverse associations of overall PDI and hPDI with MRI-PDFF, while uPDI was positively associated with liver fat content. The association between hPDI and NAFLD risk was significantly greater among participants with lower genetic risk, but associations of overall PDI and uPDI with NAFLD risk were not substantially varied by genetic risk.

Conclusions: Greater adherence to overall and healthful plant-based diets was associated with lower NAFLD risk and liver fat content regardless of genetic susceptibility, whereas an unhealthful plant-based diet was associated with higher NAFLD risk and intrahepatic steatosis. These results suggest that the quality of plant-based foods should be highlighted when recommending a plant-based diet.

Funding Sources: Dr. Chen is supported by the National Key Research and Development Program of China (2020YFC2006300), the Young Scientists Fund of the National Natural Science Foundation of China (82003461), and the Young Elite Scientists Sponsorship Program by China Association for Science and Technology (YESS20210143). Study funders have no role in the study design, collection, analysis, and interpretation of the data and the writing of the report.