Table 1

Clinical and demographic features of the study population including 4478 patients with RA and their distribution in bDMARDs monotherapy and combination therapy

Study populationMonotherapy (N=799)Combination (N=3679)P values
Demographic characteristics
Mean age (SD, years)55.48 (12.69)54.90 (12.97)55.61 (12.62)0.136
Female, n (%)3472 (77.53)614 (76.85)2858 (77.68)0.607
Clinical characteristics
 Disease duration, n (%)
  <1 years1028 (22.96)153 (19.15)875 (23.78)<0.001
  >1 to ≤2 years1106 (24.7)188 (23.53)918 (24.95)
  ≥3 to ≤5 years1064 (23.76)171 (21.40)893 (24.27)
  >5 years1280 (28.58)287 (35.92)993 (26.99)
 Number of comorbidities=0, n (%)3941 (88.01)683 (85.48)3258 (88.56)0.004
 Number of comorbidities=1, n (%)416 (9.29)80 (10.01)336 (9.13)
 Number of comorbidities=2, n (%)105 (2.34)30 (3.75)75 (2.04)
 Number of comorbidities ≥3, n (%)16 (0.36)6 (0.75)10 (0.27)
 Charlson Comorbidity Index*, mean (SD)1.16 (0.48)1.22 (0.60)1.15 (0.45)0.009
 CHD, n (%)66 (1.47)16 (2.00)50 (1.36)0.193
 Heart failure, n (%)12 (0.27)5 (0.63)7 (0.19)0.047
 Vascular pathology, n (%)10 (0.22)4 (0.50)6 (0.16)0.086
 Dementia, n (%)1 (0.02)1 (0.13)0 (0.00)0.178
 COPD, n (%)49 (1.09)11 (1.38)38 (1.03)0.451
 Mild hepatic disease , N (%)73 (1.63)24 (3.00)49 (1.33)0.002
 Diabetes, n (%)276 (6.16)41 (5.13)235 (6.39)0.195
 Renal disease, n (%)32 (0.71)18 (2.25)14 (0.38)<0.001
 Neoplasm , n (%)67 (1.50)16 (2.00)51 (1.39)0.198
 Leukaemia/lymphoma, n (%)1 (0.02)1 (0.13)0 (0.00)0.178
 Previous infections, n (%)822 (18.36)140 (17.52)682 (18.54)0.501
 Concomitant NSAIDs, n (%)3386 (75.61)485 (60.70)2901 (78.85)<0.001
 Concomitant GCs, n (%)3045 (68.00)428 (53.57)2617 (71.13)<0.001
 GCs dose (mg/day), mean (SD)2.23 (3.08)1.85 (3.32)2.31 (3.01)<0.001
  • *Diabetes with end-organ damage, AIDS, cerebrovascular disease, peptic ulcer and hemiplegia are not shown due to absence of cases in monotherapy group.

  • †Severe hepatic disease and metastatic neoplasms are not shown due to absence of cases in both groups.

  • bDMARD, biological disease-modifying antirheumatic drug; CHD, coronary heart disease; COPD, chronic obstructive pulmonary disease; GC, glucocorticoid; NSAIDs, non-steroidal anti-inflammatory drugs; RA, rheumatoid arthritis.