Associations of Serum Retinol and α-Tocopherol Levels with Uric Acid Concentrations: Analysis of a Population-Based, Nationally Representative Sample

The effects of serum retinol and α-tocopherol on serum uric acid levels have not been established, especially in Asian people. This study evaluated the independent associations of retinol and α-tocopherol with serum uric acid levels in the Korean population. We included 6023 participants aged ≥ 19 years from the Korean National Health and Nutrition Examination Survey (KNHANES). Serum retinol and α-tocopherol levels were divided into quintiles, and a multivariate linear regression model was used to evaluate the association of serum retinol and α-tocopherol levels with uric acid concentration. Additionally, we used multivariate logistic regression to examine the relationships between the levels of these micronutrients and hyperuricemia. Serum retinol levels were positively associated with uric acid concentrations in a dose-dependent fashion in both sexes (p(trend) < 0.001); the difference in serum uric acid levels between the highest and lowest quintiles of retinol levels was 0.57 mg/dL in men and 0.54 mg/dL in women. In the multivariable logistic model, the hyperuricemia risk increased linearly with the increase in serum retinol level, regardless of sex (p(trend) < 0.001). Although the serum α-tocopherol level appeared to be significantly associated with increased uric acid levels, this association was nullified after adjusting for serum retinol levels. Serum retinol levels were positively associated with serum uric acid levels and hyperuricemia in a dose-response fashion. Maintaining serum retinol concentrations under sub-toxic levels might be necessary to prevent hyperuricemia-related adverse health outcomes.