Association between polycyclic aromatic hydrocarbons and rheumatoid arthritis

Objective To analyze the association between polycyclic aromatic hydrocarbons(PAHs)exposure and rheumatoid arthritis(RA)based on large sample data. Methods The RA patients(RA group)and non-RA patients(non-RA group)with complete data were selected from the National Health and Nutrition Survey Database in the United States(NHANES)(2005—2014). The logistic regression model was used to analyze the association between 8 monohydroxylated(OH-)PAH metabolites in the urine and RA. Results A total of 357 RA patients and 5, 256 non-RA participants were included.After adjusting the confounding factors by logistic analysis, the level of OH-PAHs mixture at the highest quartile(Q4)was associated with increased risk of RA compared with that at the lowest quartile(Q1)(OR=1.60, 95%CI: 1.16-2.23). For a single kind of OH-PAHs, the Q4 levels of 1-hydroxynaphthalene(OR=1.59, 95%CI: 1.14-2.23), 2-hydroxynaphthalene(OR=1.66, 95%CI: 1.19-2.32), 2-hydroxyfluorene(OR=1.61, 95%CI: 1.17-2.22), 3-hydroxyfluorene(OR=1.64, 95%CI: 1.18-2.27)and 1-hydroxyphenanthrene(OR=1.38, 95%CI: 1.00-1.94)were all associated with significantly increased risk of RA compared with the Q1 level(all P<0.05). However, the Q2 level of 1-hydroxypyrene(OR=0.60, 95%CI: 0.43-0.83)was related to a decreased incidence of RA(P<0.01). Conclusions OH-PAHs mixed exposure is a risk factor for RA.The association between the level of individual OH-PAH and the rate of RA is bidirectional and is depended on the type and concentration of OH-PAHs. Key words: Arthritis, rheumatoid; Polycyclic compounds; Hydrocarbons, aromatic