Chinese herbal medicine reduces the risk of readmission in patients with rheumatoid arthritis combined with hyperlipidemia: A population‑based retrospective cohort study

Rheumatoid arthritis (RA) is a systemic autoimmune disease that is associated with high degrees of disability and mortality. Patients with RA are generally more prone to a multitude of comorbidities, with hyperlipidemia (HL) one of the most frequently observed. Therefore, the present study investigated the possible association between Chinese herbal medicine (CHM) treatment and the risk of readmission in patients with RA combined with HL (RA-HL). The aim of the present study was to potentially provide an evidence-based strategy for decreasing the risk of readmission in patients with RA-HL. The present study enrolled 839 patients with RA admitted to the First Affiliated Hospital of the Anhui University of Chinese Medicine from June 2014 to June 2015. Subsequently, 425 patients with RA were included into the present study after those with incomplete follow-up and laboratory parameter data were excluded. These 425 patients were then classified into the RA-HL and RA-non-HL groups, before incidences of sex distribution, age group, medication and readmission with propensity score matching were all compared. In total 263 patients with RA-HL were then included and arranged into the CHM and non-CHM groups. In particular, the variables of age, sex and diagnosis year between one patient in the CHM group and one in the non-CHM group were adjusted with propensity score matching to decrease selection bias and interference from confounding factors. Finally, 127 patients with RA-HL were included into the CHM group and 127 patients with RA-HL were allocated into the non-CHM group. The proportion of readmitted patients (including RA-HL and RA-non-HL, RA-CHM and RA-non-CHM) was analyzed and compared using the χ(2) test and Kaplan-Meier curves. Bivariate logistics regression analysis was used to evaluate the possible factors that can influence the readmission of patients with RA-HL, whereas the potential association between CHM and improvements in the clinical indicators of the patients with RA-HL was assessed using association rules based on Apriori algorithm. It was found through the follow-up data that patients with RA-HL were at higher risk of readmission compared with that in those with RA-non-HL (P<0.05). The CHM treatments included both oral CHM decoction and Chinese patent medicine, including Xinfeng capsule and Huangqin chubi capsule, which may reduce the risk of readmission and improve the recovery of immune-inflammatory indicators in patients with RA-HL (P<0.05). Overall, CHM, as a protective factor, is associated with a reduced risk of readmission in RA-HL.