Association Between Dioxin Exposure And Hyperuricemia In Adults

Objective: With rapid changes in living environments and living standards,the prevalence of hyperuricemia is rising rapidly globally,leading to more severe disease and socio-economic burden,especially in developed countries.In recent years,the association between environmental pollutants and hyperuricemia has attracted much attention.The association between exposure to dioxins and hyperuricemia has been widely reported at home and abroad.But these studies are usually based on multichemical linear models.Although this method takes into account the fact that human are exposed to a variety of chemicals at the same time,it ignores the possibility of high correlation between dioxin compounds and the possibility of complex nonlinear and non-additive relationship between chemicals mixture and hyperuricemia,and it fails to identify chemical components that have a greater impact on hyperuricemia.The application of flexible statistical methods may be better suited to explore complex associations between exposure to mixed dioxins and hyperuricemia.Therefore,in this study,we simultaneously applied three different statistical models to evaluate the association between exposures to single or mixed dioxins and hyperuricemia,and expected to provide new insights into the association between exposure to dioxins mixture and hyperuricemia by comparing the results of these three models.Methods: Subjects in this study were selected from the National Health and Nutrition Examination Survey(NHANES)database of aged 20 years and older in2003-2004.There were 7 dioxin-like polychlorinated biphenyls(DL-PCBs),3polychlorinated dibenzo-p-dioxins(PCDDs),and 2 polychlorinated dibenzofurans(PCDFs)were included in the final analysis.Hyperuricemia was defined as serum uric acid ≥7.0 mg/d L(416 μmol/L)in males and ≥6.0 mg/d L(357 μmol/L)in females.We fitted multivariate logistic regression,weighted quantile sum(WQS)regression and Bayesian kernel machine regression(BKMR)models to assess the association of exposure to single or mixed dioxins with hyperuricemia.Results:1.Study population characteristics: There were 1008 participants in our study.The prevalence of hyperuricemia was 20.04%.Participants with hyperuricemia tended to be older,were more likely to be Mexican American,and had higher incidences of obesity,diabetes,hypertension,and chronic kidney disease.2.Multivariate logistic regression analysis of the association between exposure to dioxins and hyperuricemia: after adjusting for all covariables,logistic regression of a single chemical showed that PCB74(OR: 1.37;95% CI: 1.03-1.84),PCB105(OR: 1.39;95% CI: 1.13-1.71),PCB118(OR: 1.44;95% CI: 1.14-1.82)and 1,2,3,4,6,7,8-HPCDD(OR: 1.38;95% CI: 1.07-1.79)were positively associated with hyperuricemia.Considering the confounding effects of other dioxins,we further conducted a logistic regression model including all dioxins,and the results showed that only PCB28 and1,2,3,4,6,7,8-HPCDD were significantly positively associated with hyperuricemia.3.WQS regression model to evaluate the association between exposure to dioxins and hyperuricemia: In the WQS regression analysis,WQS index showed a significant positive association with hyperuricemia regardless of whether covariates were adjusted,suggesting that the total body burden of 12 dioxins was significantly positively association with hyperuricemia.In the model adjusted for all covariates,the weight of1,2,3,4,6,7,8-HPCDD in the WQS index was the highest(0.22),indicating that1,2,3,4,6,7,8-HPCDD played the most important roles on hyperuricemia.4.The BKMR model evaluated the association between exposure to dioxins mixture and hyperuricemia: When all dioxin exposure levels were fixed at or above the60 th percentile,there was a significant positive association between dioxins mixture exposure and hyperuricemia compared to their 50 th percentile,with PCB118 driving the dominant effect.The univariate expose-response function showed positive associations of PCB105 and PCB118 with hyperuricemia when exposure levels of other dioxins were fixed at their 50 th percentile level.The bivariate exposure-response functions of BKMR indicated that there was no potential interaction between dioxins on hyperuricemia.Conclusion:1.Mixed exposure of 12 dioxins was positively associated with hyperuricemia.2.Among the 12 dioxins,PCB105,PCB118 and 1,2,3,4,6,7,8-HPCDD were the most important chemicals associated with hyperuricemia.3.There was no potential interaction between dioxins on hyperuricemia.4.The association between exposure to dioxins mixture and hyperuricemia was stable and was not affected by chronic kidney disease.Due to the advantages and disadvantages of these three statistical models,our study comprehensively and systematically evaluated the association between dioxins exposure and hyperuricemia.