The Association Between Dietary Acidity and Clinical Symptoms in Patients With Rheumatoid Arthritis

This study aimed to investigate the relationship between dietary acidity load and clinical symptoms in the patients with rheumatoid arthritis (RA). This case-control study examined 55 patients with RA and 215 healthy individuals in a Ravansar non-communicable diseases (RaNCDs) cohort study, Iran. Participants' food intakes were assessed using a validated food frequency questionnaire. The dietary acidity was calculated using potential renal acid load (PRAL), net endogenous acid production (NEAP), and dietary acid load (DAL) scores. The patients with RA were identified based on the self-reporting, medications history, and the approval of the cohort center physician following patients' examination. The odds ratio (OR) of joint stiffness in fully adjusted model was greater in the upper median of dietary acidity than in the lower median (PRAL: odds ratio [OR], 1.18; 95% confidence interval [CI], 0.59-2.36), but there was no statistically significant difference. The OR of joint pain in the upper median of dietary acidity was less than in the lower median in fully adjusted model (PRAL: OR, 0.70; 95% CI, 0.46-1.29), but the difference was not statistically significant. After adjusting potential confounders, people in the upper median of dietary acidity had a higher OR of developing RA than those in the lower median (PRAL: OR, 1.39; 95% CI, 0.70-2.76); however, it was not statistically significant. There was not any statistically significant relationship among dietary acidity and the odds of joint pain, joint stiffness, and developing RA.