Association of dairy intake with premature coronary artery disease development: Result of Iran Premature Coronary Artery Disease (IPAD) Study

Abstract Background Evidence has argued about the association between dairy intake and premature coronary artery disease (PCAD) development aimed to be discussed in this study. Methods This case-control study was conducted on 813 individuals with PCAD and 471 healthy controls. The diary intake of participants was assessed by a validated semi-quantitative food frequency questionnaire. Binary and ordinal logistic regression was applied to determine the association of dairy intake with PCAD and its severity, respectively. Results Compared to the first quartile, the highest quartile of total dairy consumption was associated with an increased risk of PCAD [ Odds ratio (OR):1.56; 95% confidence interval (95%CI): 1.13, 2.14; P = 0.008] in the crude model. It was strengthened after full adjustment [OR: 2.44, 95% CI; 1.50,3.97; P < 0.001]. Both low-fat and high-fat dairy intake revealed no association with the risk of PCAD in the crude model. However, in the fully adjusted model, respectively highest quartile of high-fat and low-fat dairy intake had a relationship with a higher risk of SCAD. [(OR:1.68; 95%CI: 1.05,2.69; P-value for trend = 0.011) and (OR:1.99; 95%CI: 1.20,3.27; P-value for trend = 0.005). After adjustment for potential confounders, the most frequent intake of high-fat dairy was related to increased severity of PCAD (OR:1.84; 95%CI: 1.27,2.68), but not for total and low-fat dairy intake (OR:0.98; 95%CI: 0.67,1.44 and OR: 0.74; 0.51,1.07; respectively). Conclusion Dairy consumption regardless of its fat content was associated with increased risk for PCAD. The severe atherosclerotic manifestations in the coronary arteries were only associated with higher intake of high-fat dairy.