Dietary determinants of oxidized-low-density lipoprotein antibodies in a sample of pharmacologically untreated non-smoker subjects: data from the Brisighella heart study.

BACKGROUND: Oxidation makes LDL an immunogenic substrate, stimulating the production of specific autoantibodies against oxidized LDL (ox-LDL Ab). The demonstration of ox-LDL Ab presence in serum indicates the existence of a long-term lipid peroxidation in vivo. OBJECTIVES: The aim of the study is to evaluate the influence of a large number of dietary variables on the dosage of ox-LDL Ab in pharmacologically untreated healthy subjects. MATERIAL AND METHODS: The Brisighella Heart Study (BHS) is a prospective, population-based longitudinal epidemiological investigation involving 2939 randomly selected adult subjects, resident in the northern Italian rural town of Brisighella. For this study, we analyzed the dietary, clinical and laboratory data of 265 (M: 101, W: 164) pharmacologically untreated non-smoker subjects, evaluating the factors potentially affecting their ox-LDL Ab dosage. RESULTS: In a multivariate analysis, including age, BMI, hemodynamic and laboratory parameters, the only significant predictor of log-ox-LDL Ab level was age (HR -0.19; 95%CI -0.115 - -0.104, p=0.001; adjusted R2=0.581). Including in the analysis the considered nutritional variables, the best model predicting the log-ox-LDL Ab level included age (HR -0.11; 95%CI -0.116 - -0.105, p<0.001), the percentage of kcal derived from lipids (HR -0.12; 95%CI -0.134 - -0.112, p<0.001), copper (OR 0.77; 95%CI 0.475 - 1.076, p<0.001) and zinc (HR -0.22; 95%CI -0.282 - -0.163, p<0.001; adjusted R2=0.358). CONCLUSIONS: In this population sample of healthy subjects, the main considered dietary components do not influence the ox-LDL Ab level in a clinically relevant manner.