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 population | Monotherapy (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 years | 1028 (22.96) | 153 (19.15) | 875 (23.78) | <0.001 |
| >1 to ≤2 years | 1106 (24.7) | 188 (23.53) | 918 (24.95) | |
| ≥3 to ≤5 years | 1064 (23.76) | 171 (21.40) | 893 (24.27) | |
| >5 years | 1280 (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.