Table 1: Demographic, clinical characteristics and risk factors for nosocomial infection in RA patients.

VariableTotal patientsInfectionNo infectionUnivariate analysisMultivariate logistic regression analysis
( 𝑁 = 2 4 5 2 ) ( 𝑛 = 5 5 3 ) ( 𝑛 = 1 8 9 9 )P valueOdds ratio (95%CI)P value

Ages, mean (SD), years59.81 (12.71)59.66 (13.51)58.69 (12.47)0.113
Female, %2034 (82.90)476 (86.07)1558 (82.04)0.0260.70 (0.53–0.92)0.012
Course of diseases, median (IQR), years9.00 (3.00–16.00)9.00 (3.00–16.00)9.00 (3.00–17.00)0.344
Duration in hospital, mean (SD), days11.49 (5.27)12.31 (6.32)11.25 (4.89)<.0011.03 (1.01–1.05)<.001
Organs involved, No. mean (SD)3.83 (0.67)4.75 (0.79)3.85 (0.63)0.0060.82 (0.72–0.93)0.003
Comorbidities, No.mean (SD)0.56 (0.81)0.60 (0.81)0.54 (0.80)0.143
DMARDs, No. mean (SD)1.90 (0.721)2.00 (0.743)1.87 (0.71)<.0011.22 (1.06–1.40)0.005
Corticosteroids dosage, mean (SD), mg/d3.55 (8.43)4.33 (9.97)3.31 (7.92)0.0271.02 (1.01–1.03)0.003
Pulse CTX, %95 (3.87)31 (5.6)64 (3.3)0.017
Etanercept, %1226 (50.00)263 (47.56)963 (50.71)0.192
WBC counts, median (IQR), ×109/L6.40 (5.00–7.90)6.60 (2.51–8.20)6.38 (3.00–7.80)0.0051.04 (1.00–1.08)0.051
PLT, median (IQR), ×1012/L232.00 (173.00–302.00)236.00 (171.00–306.00)228.00 (174.00–302.00)0.557
E., median (IQR), ×109/L0.14 (0.09–0.25)0.14 (0.09–0.29)0.14 (0.09–0.25)0.013
HB, median (IQR), g/L113.00 (102.00–125.00)110.00 (100.00–122.00)114.00 (103.00–126.00)<.001
Globin, median (IQR), g/L30.00 (27.00–34.50)30.00 (26.00–34.00)30.10 (27.00–34.60)0.088
ALB, median (IQR), g/L35.00 (30.00–39.20)34.00 (28.00–38.00)35.80 (31.00–40.00)<.0010.98 (0.97–0.99)<.001
ESR, median (IQR), mm/H36.00 (15.00–67.00)38.00 (17.20–76.00)36.00 (14.00–65.00)0.006
CRP, median (IQR), mg/L8.00 (2.53–28.10)12.10 (.35–41.00)7.88 (2.28–25.3)<.0011.03 (1.02–1.04)0.021
IgG, median (IQR), mg/L12.60 (4.76–16.00)12.10 (6.80–15.70)12.70 (2.80–16.00)0.873
IgA, median (IQR), mg/L2.68 (0.87–3.70)2.74 (1.01–3.81)2.60 (0.7–3.70)0.356
IgM, median (IQR), mg/L1.00 (0.20–1.64)1.00 (0.40–1.56)1.04 (0–1.67)0.532

Data are number (%) of patients, unless otherwise indicated. SD: standard deviation. IQR: interquartile range. CI: confidence interval. Organs involved, No.: the number of involved organs. Comorbidities, No.: the number of comorbidities: hypertension, diabetes mellitus, malignancy, chronic lung disease, congestive heart failure, cardiac arrhythmia, renal failure, liver disease. DMARDs, No.: the numbers of DMARs (disease-modifying antirheumatic drugs). WBC: white blood cell. PLT: platelet. E: eosinophils. HB: homoalbumin. ALB: albumin. ESR: erythrocyte sedimentation rate. CRP: C-reactive protein.