Comparison of two statistical models in predicting the outcome of female systemic lupus erythematosus patients in China

Objectives: Comparing two different statistical models to predict female SLE patients’ outcome and analyze some related factors. Methods: 1072 female SLE patients were from the Provincial Hospital of Anhui Province and The First Ancillary Hospital of Anhui Medical University from 1990 to 2000. Two types of statistical models including loglinear and Cox proportional hazard model were performed according to this data. Results: Marriage situation, family place, admission situation, whether coming from a different division, nosocomial infection, first occurrent or not and number of drug types had significant effects on LOS after fitting of a loglinear model. Related factors from Cox proportional hazard model were little more than those selected from loglinear model. Based on the former model, a female SLE patient could be predicted that how long she would stay in hospital. But from the latter model, we could predict the ratio of the probability of improvement between different groups of female SLE patients with different individual or clinical characteristics. Conclusions: Factors affecting the length of stay of female SLE patients could be selected from either loglinear model or Cox model. But these two models would be used to do different predictions.

Anti-cyclic citrullinated peptide antibody predicts the development of rheumatoid arthritis in patients with undifferentiated arthritis

Background:Clinical outcomes of undifferentiated arthritis(UA)are diverse,and only 40%of patients with UA develop rheumatoid arthritis(RA)after 3 years.Discovering predictive markers at disease onset for further intervention is critical.Therefore,our objective was to analyze the clinical outcomes of UA and ascertain the predictors for RA development.Methods:We performed a prospective,multi-center study from January 2013 to October 2016 among Chinese patients diagnosed with UA in 22 tertiary-care hospitals.Clinical and serological parameters were obtained at recruitment.Follow-up was undertaken in all patients every 12 weeks for 2 years.Predictive factors of disease progression were identified using multivariate Cox proportional hazards regression.Results:A total of 234 patients were recruited in this study,and 17(7.3%)patients failed to follow up during the study.Among the 217 patients who completed the study,83(38.2%)patients went into remission.UA patients who developed RA had a higher rheumatoid factor(RF)-positivity(42.9%vs.16.8%,χ^2=8.228,P=0.008),anti-cyclic citrullinated peptide(CCP)antibodypositivity(66.7%vs.10.7%,χ^2=43.897,P<0.001),and double-positivity rate of RF and anti-CCP antibody(38.1%vs.4.1%,χ^2=32.131,P<0.001)than those who did not.Anti-CCP antibody but not RF was an independent predictor for RA development(hazard ratio 18.017,95%confidence interval:5.803–55.938;P<0.001).Conclusion:As an independent predictor of RA,anti-CCP antibody should be tested at disease onset in all patients with UA.