Clinical observation of hypofibrinogenemia induced by the treatment of tocilizumab in rheumatic diseases and exploration of risk factor for hypofibrinogenemia

Abstract

The objective of this study was to analyze the changes in plasma brinogen (FIB) levels during tocilizumab (TCZ) treatment in patients with rheumatic diseases, to clarify the incidence of hypo brinogenemia and its possible risk factors, and establish a nomogram model for predicting the probability of hypo brinogenemia in rheumatoid arthritis (RA) patients treated with TCZ. MethodsClinical data of patients treated with TCZ at the department of Rheumatology and Immunology, the First A liated Hospital of Xi'an Jiaotong University from January 2014 to October 2021 were retrospectively analyzed to observe the incidence of hypo brinogenemia in several rheumatic diseases at different time points. The risk factor of hypo brinogenemia in RA patients treated with TCZ was determined by using Cox regression analysis. Based on the results of Cox regression analysis, a nomogram for predicting the probability of hypo brinogenemia in rheumatoid arthritis (RA) patients treated with TCZ was established and validated through RStudio software. ResultsA total of 83 TCZ-treated patients were enrolled in this study, and 32 (38.55%) patients developed hypo brinogenemia during TCZ treatment. There were 8 males and 24 females in the FIB-reduced group, with an average age of 38.25 ± 16.92 years. Hypo brinogenemia was most common in TCZ-treated patients with takayasu arteritis (TA) and RA. Hypo brinogenemia typically occurs within 3 months after TCZ treatment. In RA patients treated with TCZ, platelet distribution width, parathyroid hormone, bone mineral density, tender joint count, and swollen joint count were independent risk factors for the occurrence of hypo brinogenemia. The nomogram based on the above risk factors could effectively predict the probability of hypo brinogenemia in RA patients receiving TCZ. ConclusionAlthough bleeding symptoms were not observed in this study, the incidence of hypo brinogenemia remained high after TCZ treatment, usually occurring within 3 months of treatment. Therefore, it is necessary to monitor FIB levels during TCZ treatment. In addition, clinicians can use the nomogram model developed from this study to predict the incidence of hypo brinogenemia after TCZ treatment in RA patients.