Table 2.

Univariate logistic regression analysis of antibody response after COVID-19 mRNA vaccination in patients.

OR95% CIP
Univariate logistic regression analysis
Sex, female (ref)0.910.50–1.670.77
Age, yrs0.980.96–1.000.09
Time from vaccination to blood sample, days1.000.99–1.010.61
Diagnosis
      Rheumatoid arthritisRefRefRef
      Systemic lupus erythematosus0.570.19–1.690.31
      AAV (GPA/EGPA)0.830.41–1.690.61
      Polymyositis/dermatomyositis0.360.13–1.020.06
      Systemic sclerosis1.330.35–5.070.67
      Other RDs2.670.82–8.710.10
RTX exposure
      RTX treatment within last 15 months0.210.10–0.40< 0.001
      Time between last RTX and vaccination, months1.061.03–1.09< 0.001
      Total no. of RTX infusions0.960.92–1.010.10
      Total RTX dose, mg0.970.92–1.020.18
      Time from first to last RTX treatment, months1.001.00–1.000.57
DMARD treatment
      None0.940.50–1.780.85
      Prednisone, yes/no (no = ref)0.490.27–0.890.02
          Prednisone dose, mg0.910.85–0.990.02
      Methotrexate1.710.90–3.250.10
      Hydroxychloroquine0.870.35–2.190.77
      Azathioprine0.230.06–0.800.02
Multivariate logistic regression analysis
Time between last RTX and vaccination, months1.081.04–1.11< 0.001
DMARD treatment
      Prednisone dose, mg0.910.84–0.990.03
      Azathioprine0.100.02–0.440.002
  • Explanatory variables in the univariate model are based on previous knowledge of association to vaccination response and evaluation of RTX exposure. Specific DMARD treatments were included if ≥ 10% of the patients received it. The multivariate model includes all explanatory variables with statistically significant effects in the univariate analysis. “Time from last RTX treatment to vaccination” and “prednisone treatment” were included as continuous variables. Values in bold are statistically significant. AAV: antineutrophil cytoplasmic antibody–associated vasculitis; COVID-19: coronavirus disease 2019; DMARD: disease-modifying antirheumatic drug; EGPA: eosinophilic granulomatosis with polyangiitis; GPA: granulomatosis with polyangiitis; OR: odds ratio; RD: rheumatic disease; RTX: rituximab.