Association of the cardiovascular health diet index and concise healthy diet score with non-alcoholic fatty liver disease: a secondary analysis of a case-control study

Purpose Diet quality plays a pivotal role in the prevention of non-alcoholic fatty liver disease (NAFLD). However, evidence on the associations between the Cardiovascular Health Diet Index (CHDI) and the Concise Healthy Diet Score (CHDS) and NAFLD remains limited, particularly in Middle Eastern populations. In this study, we investigated this association. Methods This case-control study included 675 Iranian adults (225 patients with NAFLD and 450 controls). Dietary intake was evaluated utilizing a validated 168-item food frequency questionnaire. Multivariable logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for NAFLD after adjustment for potential confounders. Results Among the NAFLD cases, the mean CHDI score was 55.9 ± 10.3, and the median CHDS score was 2.00 (IQR: 1.00-3.00). Among the controls, the mean CHDI score was 62.2 ± 10.9, and median CHDS score was 2.00 (IQR: 2.00-3.00). In multivariable adjusted model, participants in the highest tertile of the CHDI had an 84% lower odds of NAFLD compared with those in the lowest tertile (OR = 0.16; 95%CI:0.08-0.32; P for trend < 0.001). Similarly, for the CHDS, participants in the highest category had 69% lower odds of NAFLD compared with the lowest category (OR = 0.31;95%CI:0.17-0.60; P for trend = 0.001). These inverse associations were also observed per one‑unit increase in each score, with an 8% reduction for CHDI (OR = 0.92;95%CI:0.90-0.95, P < 0.001) and a 36% reduction for CHDS (OR = 0.64;95%CI:0.49-0.85, P = 0.002). Conclusion Our findings suggested that higher overall dietary quality, characterized by higher score of the CHDI and CHDS, was independently associated with lower odds of NAFLD in adult population.