Analysis on changes in complement C3,C4 and immunoglobin levels in patients with rheumatoid arthritis

Deng Wenjie; Wang Chunxiang; Liu Ying

doi:10.3969/j.issn.1674-7151.2025.04.013

Abstract：Objective To analyze changes in complement C3,C4 and immunoglobulin(Ig)levels in patients with rheumatoid arthritis(RA).Methods The clinical data of 235 patients with RA in Longyan People's Hospital from January 2024 to January 2025 were retrospectively collected and included in observation group.Based on RA disease activity score(DAS28),the patients were categorized into high-activity group(55 cases;DAS28>5.1),moderate-activity group(59 cases;3.2<DAS28≤5.1),low-activity group(61 cases;2.6<DAS28≤3.2)and remission group(60 cases;DAS28≤2.6).Additionally,60 healthy individuals undergoing physical examinations during the same period were selected as control group.The levels of complement C3,C4 and IgA,IgM,IgG were detected using immunoturbidimetry,and the differences in above indicators between observation group and control group,and among patients with different disease activities in observation group were compared.Pearson correlation analysis was employed to evaluate the relationship between disease activity and above indicators.Results The observation group showed significantly higher levels of complement C3,C4 and IgA,IgM,IgG compared to control group[complement C3(g/L):1.81±0.46 vs.0.92±0.23;complement C4(g/L):0.62±0.08 vs.0.41±0.11;IgA(g/L):4.23±1.08 vs.1.49±0.36;IgM(g/L):3.84±1.06 vs.1.34±0.35;IgG(g/L):16.44±3.76 vs.11.94±1.78;all P<0.05].The levels of complement C3,C4 and IgA,IgM,IgG in high-activity group were significantly higher than those in moderate-activity group,low-activity group and remission group[complement C3(g/L):2.34±0.52 vs.2.07±0.46,1.80±0.48,1.17±0.33;complement C4(g/L):0.76±0.08 vs.0.70±0.09,0.60±0.07,0.43±0.05;IgA(g/L):6.25±1.29 vs.4.97±1.12,3.63±0.95,2.26±0.60;IgM(g/L):4.79±1.64 vs.4.25±0.98,3.59±0.74,2.83±0.58;IgG(g/L):22.84±4.39 vs.17.59±3.66,14.14±3.31,11.79±3.24;all P<0.05].The moderate-activity group showed significantly higher levels of complement C3,C4 and IgA,IgM,IgG than low-activity group and remission group,while the low-activity group exhibited significantly higher levels of above markers compared to remission group(all P<0.05).Pearson correlation analysis revealed positive correlations between disease activity and complement C3,C4 and IgA,IgM,IgG levels(r values were 0.404,0.462,0.397,0.415 and 0.554,P values were 0.007,<0.001,0.008,0.010 and<0.001,respectively).Conclusions The disease activity of patients with RA is closely associated with the complement and antibody markers.Monitoring these indicators could provide valuable insights for clinical assessment and treatment.