Association between Index of Nutritional Quality (INQ) and Severity of Coronary Artery Disease: A Cross-Sectional Study of Patients Undergoing Coronary Angiography

Background: Coronary artery disease (CAD) is the predominant form ofcardiovascular disease (CVD) and a major cause of mortality globally. This studyaimed to investigate the association between the Index of Nutritional Quality(INQ) for specific nutrients and coronary artery stenosis severity, lipid profiles,and body composition in patients undergoing coronary angiography. Methods: Inthis cross-sectional study of 612 adults (35-75 years) undergoing coronaryangiography, dietary intake was assessed using a validated 178-item foodfrequency questionnaire (FFQ). The INQ was calculated for various nutrients.Coronary artery stenosis was quantified using Gensini (GS) and SYNTAX (SS)scores. Results: A higher INQ for linolenic acid was significantly associated withlower odds of vascular occlusion based on SS after full adjustment (OR=0.5; 95%CI: 0.28-0.88). A higher INQ for fiber was associated with lower total cholesterol(TC) and low-density lipoprotein cholesterol (LDL-C), while a higher INQ forprotein was associated with elevated high-density lipoprotein cholesterol (HDL-C). Conversely, a higher INQ for riboflavin and vitamin D was correlated withincreased TC. A higher INQ for vitamin B6 was linked to increased TC,triglycerides (TG), and visceral fat, but a lower body mass index (BMI).Conclusion: These findings suggest that the quality of nutrient intake, particularlyhigher linolenic acid and fiber, is associated with a better cardiometabolicprofile and reduced coronary stenosis, highlighting the potential importance ofnutrient quality assessment in the dietary management of CAD. Prospectivestudies are needed to confirm these findings