The quality of plant-based dietary patterns affects the ten-year cardiovascular disease risk of participants with non-alcoholic fatty liver disease: highlights from a population-based cohort study

Abstract

Background/Introduction: Some plant-based diets like the Mediterranean diet have been suggested to have a beneficial impact on liver disease. However, the quality of plant-based diets - in general - varies. Purpose: The association between plant-based diet indices and nonalcoholic fatty liver disease (NAFLD) as well as their interaction on ten-year cardiovascular disease incidence was examined. Methods: A prospective study was conducted during 2001-2012 studying n=1,514 males and n=1,528 females (aged >18 years old) free of CVD. Healthy metabolic status was defines as absence of all NCEP ATP III (2005) metabolic syndrome components (excluding waist circumference). Follow-up CVD assessment (2011-2012) was achieved in n=2,020 participants (n=317 cases). Overall, healthful and unhealthful plant-based dietary indices (PDI, hPDI and uPDI) were created through a standard procedure; hPDI was principally characterized by increased consumption of fruits/vegetables, whole grains, nuts, legumes, oils, tea/coffee while uPDI was related with increased intake of juices, sweetened beverages, refined grains, potatoes and sweets. NAFLD was defined according to validated liver steatosis indices. Results: In total, n=707 (35%) participants presented NAFLD at baseline. Ranking from 1st to 3rd PDI tertile, NAFLD prevalence was 40.3%, 35.6% and 30.9%, respectively (p=0.04). Multiadjusted analysis revealed significant inverse associations between PDI and NAFLD prevalence [Odds Ratio (OR) (3rd vs. 1st tertile)=0.60 95% Confidence Interval (95% CI) (0.35, 0.92)] as well as hPDI [OR (3rd vs. 1st tertile) = 0.75 95% CI (0.64, 0.89)]. On the other side, increased uPDI had a positive association with NAFLD prevalence [OR (3rd vs. 1st hPDI tertile) = 1.22 95% CI (1.05, 1.34)]. NAFLD predicted CVD in multi-adjusted model [Hazard Ratio (HR) = 1.35, 95% CI (1.08, 2.10)]. Subgroup analyses according to participants' adherence to overall, healthy and unhealthy plant-based patterns revealed that this observation remained significant in the following cases: participants in the 1st PDI tertile, [HR=1.40, 95% CI (1.15, 2.09)] and participants in the 1st hPDI tertile [HR=1.47, 95% CI (1.22, 2.12)]. Conclusions: Lower adherence to plant-based diet was associated with substantially higher long-term CVD risk for a NAFLD individual. Most importantly, the healthy or unhealthy food choices within this pattern seemed to determine liver steatosis progression and in turn cardiometabolic health.