Association of blood ethylene oxide levels with osteoarthritis and rheumatoid arthritis: Evidence from NHANES (2013–2020)

Objectives

Osteoarthritis (OA) and rheumatoid arthritis (RA) are common conditions with important public health implications. The role of environmental toxins in their pathogenesis is increasingly recognized; however, the impact of ethylene oxide (EO) exposure on OA and RA remains unexplored. This study investigated the association between blood EO levels and the prevalence of OA and RA in the US population, using data from the National Health and Nutrition Examination Survey (NHANES) 2013–2020.

Methods

NHANES 2013–2020 participants ≥40 years old with OA or RA who reported the condition during the NHANES interview were included. Blood EO levels were directly measured using hemoglobin adduct quantification. Univariate and multivariable logistic regression models were used to evaluate the association between EO exposure and OA and RA, adjusting for potential confounders. Restricted cubic spline (RCS) analysis was performed to assess potential non-linear relations.

Results

A total of 3476 participants (mean age: 60.0 years; 52.0 % female) were included in the study. In the unadjusted model, participants in the highest EO quintile did not have a significantly higher likelihood of OA (odds ratio [OR] = 1.23; 95 % confidence interval [CI]: 0.86–1.74) or RA (OR = 1.58; 95 % CI: 0.97–2.58) compared to those in the lowest quintile. However, after adjustment, participants in the highest EO quintile had significantly greater likelihood of having OA (aOR = 2.00; 95 % CI: 1.30–3.07) and RA (aOR = 1.81; 95 % CI: 1.08–3.03) compared to those in the lowest quintile. RCS analyses suggested no significant non-linear associations between EO exposure and OA or RA.

Conclusion

This study identified independent associations between EO exposures and an increased prevalence of OA and RA. These findings highlight the need for regulatory measures to minimize EO exposure and further investigations to confirm causal relationships.