Intermediary effect of inflammation on the association between dietary patterns and non-alcoholic fatty liver disease

Previous studies have demonstrated that nutritional status is associated with non-alcoholic fatty liver disease (NAFLD). Meanwhile, subclinical inflammation is associated with the prevalence of NAFLD. To our knowledge, however, no study has investigated the intermediary effect of inflammation on the association between dietary pattern and NAFLD. Thus, the aim of this case-control study was to explore the intermediary effect of inflammation on the association between dietary patterns and NAFLD.

Using the propensity score matching method, we generated 2043 cases and 2043 controls. Dietary intake was assessed using a valid self-administered food frequency questionnaire. Major dietary patterns in the population were derived by factor analysis. Reduced rank regression with leukocyte count as a response variable was used to derive an inflammatory pattern. NAFLD was diagnosed by liver ultrasonography and drinking history. The association between dietary patterns and NAFLD was tested using multiple conditional logistic regression analysis.

Three major dietary patterns were derived by factor analysis: sweet pattern, animal foods pattern, and traditional pattern. Compared with participants in the lowest quartile of the animal foods pattern, the odds ratio (OR; 95% confidence interval [CI]) of NAFLD in the highest quartile was 1.30 (95% CI, 1.09-1.55). After adjustment of inflammation status, the OR was weaker (OR, 1.23; 95% CI, 1.03-1.48), albeit significant. Compared with the participants in the lowest quartile of inflammatory pattern, the OR of NAFLD in the highest quartile was 1.52 (95% CI, 1.28-1.81).

The present data suggested that inflammation may mediate the association between dietary patterns and NAFLD.