The prevalence and predictors of herbal medicines usage among adult rheumatoid arthritis patients: A case-control study.

Objectives: This study was performed to evaluate the prevalence and predictors of herbal medicines usage among adult Rheumatoid Arthritis (RA) patients.

Design: In this cross-sectional, case-control study, the case group included 500 RA patients and the control group contained 500 control individuals.

Setting: The study was performed in three rheumatology, surgical, and orthopedic clinics affiliated to Shiraz University of Medical Sciences.

Main Outcome Measures: The pattern of herbal medicines usage was assessed by a researcher-made questionnaire.

Results: In this study, 51.4% of the subjects in the RA group and 36.4% of those in the control group used herbal medicines. The most frequently used herbal medicines were thyme (43.4%), chamomile (36.9%), borage (36.8%), lavender (31.2%), ginger (28.5%), and cinnamon (21.5%) among RA patients. The results showed a significant difference between the two groups with regard to usage of herbal medicines, such as chamomile, cinnamon, and ginger. Besides, the results of logistic regression analysis on RA patients showed that males (odds ratio = 0.50, p = 0.001) used herbal medicines less compared to females. Additionally, married RA patients (odds ratio = 0.35, p = 0.03), illiterate ones (odds ratio = 2.45, p = 0.001), and those with high school diplomas (odds ratio = 1.64, p = 0.02) used herbal medicines more compared to other patients.

Conclusion: This study showed that more than half of RA patients used herbal medicines. All herbal medicines (thyme, chamomile, borage, lavender, ginger, and cinnamon) had anti-inflammatory effects. Yet, further studies have to be conducted to evaluate the efficacy and safety of herbal medicines usage in RA patients.