Investigating the Relationship Between Dietary Antioxidant Index With Anthropometric Indices, Clinical Symptoms,...

Rheumatoid arthritis (RA) is a chronic autoimmune disease causing joint inflammation, pain, and deformity, significantly impacting physical and mental well-being. Sleep disturbances and obesity exacerbate symptoms, increasing disease severity. Oxidative stress plays a key role in RA progression, and diet may influence inflammation. The Dietary Antioxidant Index (DAI) reflects dietary antioxidant intake, but its link to RA symptoms is unclear. This study explores DAI associations with RA outcomes, sleep quality, anthropometric indices, and quality of life (QoL).

This cross-sectional study included 246 RA patients attending a rheumatology clinic in Ahvaz, Iran. Dietary intake was assessed using a validated food frequency questionnaire, and DAI was calculated via the Wright method. To analyze the data, we employed various statistical methods, including analysis of variance, chi-square tests, t-tests, linear and Poisson regression, as well as logistic regression, as appropriate.

In this study, patients with RA (163 females and 83 males; mean age 50.40 ± 6.33 years) were evaluated. Poor sleep quality affected 54.9% of participants. Higher DAI scores were significantly associated with lower poor sleep quality across all models (OR = 0.66, 95% CI: 0.51-0.85). Most QoL domains showed no significant link with the DAI score, except for emotional limitations and total mental health, which improved with higher scores. Central obesity, defined by waist circumference (WC), exhibited a borderline association with DAI (OR = 0.75, 95% CI: 0.56-1.00).

Our study suggests that among RA patients, higher adherence to DAI is linked with a lower likelihood of sleep deprivation, reduced central obesity as measured by WC, and a decreased rate of tender joints. However, no significant impact on overall QoL was observed. Further research involving larger populations is needed to confirm these findings.