Background: To date, few studies have examined the contribution of dietary vitamin intakes to inflammatory markers in heart failure (HF). This study was conducted to assess the association of dietary vitamin intakes with inflammatory cytokines in patients (pts) with HF. Methods: In a cross-sectional study of 91 HF patients (mean aged 63.2 yrs), we assessed usual dietary intakes by a validated food frequency questionnaire. Anthropometric measurements and demographic data were made and fasting blood samples were taken for inflammatory markers. Serum concentrations of high sensitivity C-reactive protein (hsCRP), IL-6, IL-8, IL-10, macrophage inflammatory protein (MIP)-1β and monocyte chemotactic protein (MCP)-1 were measured using ELISA method. Results: Average dietary intakes of vitamin in HF pts met the recommended Dietary Allowances (RDA), except folic acid intakes-below the RDA. Correlation analyses showed that hsCRP levels were inversely related to the dietary intakes of β-carotene (r=-0.23, p<0.05), thiamine (r=-0.25, p<0.05), vitamin C (r=-0.30, p<0.005) and folic acid (r=-0.31, p<0.005). However, multiple regression analyses revealed that those associations were not observed after adjusting for traditional risk factors for HF. Serum levels of MCP-1 were inversely associated with the dietary intakes of vitamin C (r=-0.24, p<0.05) and folic acid (r=-0.31, p<0.005), and the association remained significant only for folic acid intake after adjusting for traditional risk factors for HF (β=-0.28, p<0.01, R2=0.16). In addition, serum levels of IL-8 were inversely associated with the dietary intakes of β-carotene (r=-0.38, p<0.001), vitamin C (r=-0.34, p<0.005) and folic acid (r=-0.37, p<0.001) and all those associations remained significant after adjustment, respectively. When we further controlled all the dietary vitamin intakes in the same regression model, only β-carotene intake was found to be significant in predicting serum concentrations of IL-8 (β=-0.47, p<0.001, R2=0.47). Conclusion: Our results show associations between dietary vitamin intakes and serum concentrations of inflammatory cytokines, addressing the importance of dietary vitamin intakes in HF.
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