Abstract: Objective To evaluate the association of traditional Chinese medicine (TCM) treatment with the risk of readmission in patients with rheumatoid arthritis (RA) complicated with elevated platelet count. Methods We retrospectively collected the data of inpatients diagnosed with RA in our hospital from 2013 to 2021. The patients with elevated platelet count receiving TCM treatment were matched to those without TCM treatment using propensity score matching at the 1∶1 ratio, and the confounding factors were adjusted including gender, age, Chinese patent medicine, and external application. A Cox proportional hazard model was used to evaluate the hazard ratio (HR) of the risk of readmission, and a Kaplan-Meier curve was generated to assess the incidence of readmission in these patients. Results A total of 1176 RA patients with elevated platelet count were included in this study, including 842 patients in the TCM group and 334 patients in the non-TCM group, and after 1∶1 propensity score matching, 334 patients were included in each group. The Cox proportional hazards model showed that the readmission rate was significantly lower in TCM group than in non-TCM group (HR=0.59, 95% CI: 0.48-0.73, P<0.001), and TCM was a protective factor against readmission in RA patients with elevated platelet count. Kaplan-Meier curves demonstrated that long-term use of TCM helped to decrease the risk of readmission (Log-rank P<0.001). Association rules showed that the use of several Chinese herbal medicines and the Chinese patent medicine Xinfeng Capsule had a strong correlation with improvement of such clinical indicators as rheumatoid factor, erythrocyte sedimentation rate, and C-reactive protein. Conclusion In RA patients with elevated platelet count, the use of TCM, as a protective factor against readmission, is strongly associated with a lowered risk of readmission with a long-term association.

Key words: Traditional Chinese medicine; rheumatoid arthritis; readmission; cohort study