Introduction: The role of tea consumption on rheumatoid arthritis (RA) has been studied in recent years, but no clear conclusion has been drawn as a result of small sample size of the studies or the fact that only in vitro studies have been performed. Objectives: The aim of this study was to explore the possible association of tea consumption with RA through a large-scale, real-world study. Methods: A total of 733 RA patients were investigated from June to December, 2016. The disease activity of RA was assessed according to disease activity score 28-erythrocyte sedimentation rate. The amount and types of tea consumption were recorded by on-site self-administered questionnaires. Logistic regression models were applied to analyze the correlation between tea consumption and disease activity, adjusting for demographics, clinical and laboratory factors. Results: There was an inverse association between tea consumption and disease activity in RA patients (OR 0.66, 95% CI 0.46–0.94). Compared with non-tea drinkers, a higher-intake of tea (>750 mL/day) was associated with lower disease activity of RA (OR 0.39, 95% CI 0.19–0.79), but not low-intake (≤750 mL/day; OR 0.83, 95% CI 0.42–1.63). A significant dose-response association was found between the amount of tea consumption and disease activity (p for trend <0.01). Further hierarchical regression analysis showed that such inverse associations were mainly present in female patients (p = 0.004), non-smokers (p = 0.01) or elders (≥60 years; p = 0.01). Conclusion: Tea consumption is associated with decreased disease activity of RA, suggesting the potential beneficial effect of tea in the disease.
The usage of biological DMARDs and clinical remission of rheumatoid arthritis in China: a real-world large scale study
