Associations between oxidative balance and arthritis: insights from the National health and Nutrition Examination Survey.

Oxidative stress is implicated in arthritis development, but its associations may differ by arthritis type. This study examined the relationship between oxidative balance score (OBS) and the prevalence of rheumatoid arthritis (RA), osteoarthritis (OA), and gout in a nationally representative population. Data were obtained from the National Health and Nutrition Examination Survey (NHANES). RA and OA were analyzed using data from 2001-2018, and gout from 2007-2018. OBS was constructed from multiple dietary and lifestyle pro-oxidant and antioxidant factors. Multivariable logistic regression and restricted cubic spline analyses were used to assess associations. After adjustment for confounders, higher OBS was associated with a lower prevalence of RA, with evidence of a dose - response relationship. Stronger inverse associations were observed among participants with higher education and those who were married. Higher OBS, particularly the antioxidant component, was also associated with lower gout prevalence, showing non-linear relationships. No consistent association was observed between total OBS and OA, although lower pro-oxidant exposure was linked to lower OA prevalence. Higher OBS was associated with lower prevalence of RA and gout, while its association with OA was less clear, suggesting differential roles of oxidative balance across arthritis types.