Abstract
BACKGROUND: Although many studies have linked dietary total fat or individual fatty acids (FAs) to cardiovascular disease (CVD), the association between FA ratios – considered markers of dietary fat quality (DFQ)- and coronary artery occlusion remains unclear. METHODS: This cross-sectional study included 653 participants aged 35–75 years who underwent coronary angiography for the first time in Yazd, central Iran. Dietary intakes were assessed with a validated food frequency questionnaire (FFQ), and the DFQ indices were derived using standard formulas. Gensini (GS) and Syntax II (SS-II) scores were calculated to quantify coronary artery occlusion. Logistic regression was applied to evaluate the association between DFQ indices and coronary occlusion. RESULTS: No association was observed between DFQIs and coronary artery occlusion. In participants with obesity, individuals in the highest tertile of the lipophilic index (LI) demonstrated 82% lower odds of a high SS-II compared with those in the lowest tertile in the fully adjusted model (model 3: OR 0.18, 95% CI: 0.04–0.83; P trend = 0.09). The polyunsaturated-to-saturated fatty acids ratio (PSR) was inversely associated with the odds of high SS-II in the second versus the first tertile across all models. The PSR also showed a significant inverse association with a high GS in the fully adjusted model (OR 0.18, 95% CI: 0.04–0.80; P trend = 0.55). Among participants without diabetes, those in the second tertile of the thrombogenic index (TI) had higher odds of coronary occlusion based on GS compared with the first tertile in both model 2 (OR 2.02, 95% CI: 1.09–3.72; P trend = 0.70) and model 3 (OR 2.06, 95% CI: 1.10–3.84; P trend = 0.68). CONCLUSION: The LI and PSR may be inversely related to coronary occlusion in adults with obesity. Among participants without diabetes, the TI was associated with higher occlusion risk. Confirmation of these findings in well-designed cohort studies is warranted. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12944-026-02906-5.