Abstract
Objectives
Rheumatoid arthritis (RA) is an autoimmune disease accompanied by pain, joint stiffness, and swelling, impacting quality of life. RA is also an articular disorder affecting multiple organ systems. Oxidative stress and antioxidants may play a role in the disease process. The oxidative balance score (OBS) is a composite estimate of exogenous dietary, lifestyle, and medication factors associated with antioxidant and pro-oxidant properties. This study examined the relationship between OBS and disease activity in RA.
Methods
84 adults with RA (mean age: 52.9 ± 14.4 years; RA disease duration: 13.5 ± 9.2 years) were recruited from the NYU Langone Orthopedic Center. Disease activity was assessed via C-reactive protein, erythrocyte sedimentation rate, and the Multi-Dimensional Health Assessment Questionnaire, which includes self-reported measures of physical function, pain, & global status (summed into the RAPID3 score), fatigue, painful joint count, and duration of morning stiffness. Higher scores indicate greater disease activity. Participants completed 7-day food records, which were analyzed using Nutrition Data System for Research. OBS was calculated by analyzing 13 a priori-defined pro-oxidant (polyunsaturated fatty acid and iron) and antioxidant (selenium, vitamin C, vitamin E, α-carotene, β-carotene, lutein + zeaxanthin, lycopene, cryptoxanthine; use of aspirin and non-steroidal anti-inflammatory drugs, and alcohol) exposure factors. A higher OBS scored indicated more antioxidant and less pro-oxidant exposure. Partial correlations examined the relationship between OBS and disease activity, while controlling for age, using IBM SPSS Statistics.
Results
There was a negative association between OBS and duration of morning stiffness (r = −0.290, P = 0.010); as OBS increased, duration of morning stiffness decreased. Although not statistically significant, there was a negative trend between OBS and physical function (r = −0.180, P = 0.113), pain (r = −0.194, P = 0.086), and RAPID3 (r = −0.195, P = 0.103); as OBS increased, physical function, pain, and disease activity improved. No statistically significant relationships were seen between OBS and the other measures of disease activity.
Conclusions
In this study, a higher OBS score was associated with lower disease activity. More research is needed to understand the relationship of these lifestyle exposures to RA.
Funding Sources
NYU Steinhardt Research Challenge Grant.
Dietary Oxidative Balance Score and Disease Characteristics in Patients with Rheumatoid Arthritis (P01-036-19)