Correlation between rheumatoid factor and erythrocyte sedimentation rate in patients with rheumatoid arthritis

Objective To provide the reference for the diagnosis and treatment of rheumatoid arthritis(RA) by studying the correlation between rheumatoid factor(RF) and erythrocyte sedimentation rate(ESR) in RA patients. Methods Seventy-seven RA patients(22 males and 55 females) were enrolled in this study.Their RF and ESR were detected by nephelometry and Wilcoxon method,respectively.Positive rate of ESR and RF and their correlation were analyzed with SPSS 13.0. Results The median ESR and 95% CI were 48mm/h and 22.00-133.95mm/h respectively while the median RF and 95% CI were 32.00IU/ml and 10.10-458.10 IU/ml respectively in male patients.No significant difference was found in the positive rate of ESR and RF(χ²=1.414,P=0.157).However,ESR was positively correlated with RF(r=0.549,P=0.032).The median ESR and 95% CI were 40mm/h and 12.00-134.65mm/h respectively while the median RF and 95% CI were 40.10IU/ml and 10.10-570.10IU/ml respectively in female patients.No significant difference was found in the positive rate of ESR and RF(χ²=1.291,P=0.197).However,ESR was positively correlated with RF(γ=0.651,P=0.011). Conclusion The positive rate of ESR and RF is significantly different in male and female RA patients.RF is positively correlated with ESR in RA patients.RA patients with positive ESR but negative RF,or with positive RF but negative ESR should be further examined.