Table 3.

HAQ-DI over time with and without confounders with linear mixed models and HAQ-DI baseline as covariate.

β95% CIp
Model without confounder correction
Intercept0.2940.218–0.3700.000
TNFi mono (ref)
  TNFi + SSZ−0.084−0.187 to 0.0190.108
  TNFi + LEF−0.024−0.138 to 0.0900.680
  TNFi + other csDMARD−0.138−0.246 to −0.0310.012
  TNFi + MTX−0.135−0.195 to −0.0760.000
Time−0.004−0.007 to −0.0000.038
HAQ-DI at baseline0.6500.616–0.6830.000
Model with confounder correction
Intercept−0.018−0.212 to 0.1760.856
TNFi mono (ref)
  TNFi + SSZ−0.050−0.163 to 0.0630.385
  TNFi + LEF0.006−0.119 to 0.1300.931
  TNFi + other csDMARD−0.096−0.219 to 0.0270.125
  TNFi + MTX−0.086−0.151 to −0.0190.011
Time−0.004−0.008 to 0.0000.057
HAQ-DI at baseline0.7090.661–0.7570.000
Erosive disease negative0.0810.021–0.1420.008
DAS28 at baseline−0.027−0.051 to −0.0040.022
Age0.0070.005–0.0090.000
Disease duration0.0060.002–0.0090.001
Medication: Infliximab (ref)
  Adalimumab−0.069−0.148 to 0.0100.086
  Etanercept−0.068−0.145 to 0.0100.088
Male sex−0.067−0.123 to −0.0110.019
RF-negative0.048−0.011 to 0.1070.112
No. previous DMARD > 4 (ref)
  1−0.115−0.232 to 0.0020.054
  2−0.081−0.175 to 0.0130.092
  3−0.070−0.162 to 0.0210.133
  4−0.000−0.099 to 0.0980.992
Year of start TNFi−0.001−0.017 to 0.0130.811
  • TNFi: tumor necrosis factor inhibitor; MTX: methotrexate; SSZ: sulfasalazine; LEF: leflunomide; csDMARD: conventional synthetic disease-modifying antirheumatic drugs; ref: reference; HAQ-DI: Health Assessment Questionnaire–Disability Index; DAS28: 28-joint Disease Activity Score; RF: rheumatoid factor.