Studies (n) | Patients (n) | MD (95% CI) | Heterogeneity | P value for subgroup difference | |||
TNFi | Placebo | I² (%) | P value | ||||
Smoking | |||||||
Yes | 14 | 1409 | 685 | −0.50 (−0.67 to −0.32) | 36 | 0.09 | 0.87 |
No | 2329 | 1070 | −0.47 (−0.65 to −0.29) | 70 | 0.01 | ||
Physical activity | |||||||
Yes | 5 | 297 | 138 | −0.38 (−0.65 to −0.11) | 0 | 0.79 | 0.81 |
No | 1191 | 472 | −0.42 (−0.66 to −0.18) | 67 | 0.02 | ||
Sex | |||||||
Women | 27 | 5585 | 2513 | −0.62 (−0.75 to −0.49) | 76 | 0.01 | 0.34 |
Men | 1526 | 689 | −0.52 (−0.68 to −0.36) | 27 | 0.11 | ||
Age (years) | |||||||
>50 | 27 | 4760 | 1876 | −0.54 (−0.67 to −0.41) | 64 | 0.01 | 0.08 |
≤50 | 3315 | 1407 | −0.70 (−0.83 to −0.57) | 51 | 0.01 | ||
BMI (kg/cm²) | |||||||
≥30 | 28 | 2125 | 828 | −0.55 (−0.66 to −0.44) | 0 | 0.70 | 0.20 |
<30 | 5977 | 2492 | −0.66 (−0.80 to −0.52) | 78 | <0.01 | ||
RF status | |||||||
Positive | 28 | 6480 | 2668 | −0.65 (−0.78 to −0.52) | 75 | <0.01 | 0.12 |
Negative | 1425 | 559 | −0.50 (−0.64 to −0.37) | 5 | 0.39 | ||
ACPA status | |||||||
Positive | 13 | 3058 | 1462 | −0.50 (−0.71 to −0.29) | 82 | <0.01 | 0.62 |
Negative | 920 | 368 | −0.43 (−0.62 to −0.24) | 14 | 0.31 | ||
Disease duration (years) | |||||||
<2 | 22 | 2781 | 1416 | −0.53 (−0.72 to −0.34) | 66 | <0.01 | 0.25 |
2–10 | 1104 | 535 | −0.51 (−0.68 to −0.35) | 27 | 0.14 | ||
≥10 | 688 | 333 | −0.77 (−1.03 to −0.50) | 47 | 0.03 | ||
Baseline DAS28 | |||||||
>5.1 | 27 | 6097 | 2344 | −0.63 (−0.77 to −0.50) | 74 | <0.01 | 0.27 |
≤5.1 | 1948 | 899 | −0.53 (−0.66 to −0.39) | 52 | <0.01 |
ACPA, anticitrullinated protein antibody; BMI, body mass index; CRP, C reactive protein; Baseline DAS28, DAS28(CRP) score at baseline; DAS28, Disease Activity Score on 28 joints; ΔDAS28(CRP), DAS28(CRP) change; MD, mean difference; RF, rheumatoid factor; TNFi, tumour necrosis factor inhibitors.