Clinical trials: discrimination between patients treated with TNF blockers and placebo according to normal or increased CRP levels at baseline and according to the presence or absence of peripheral arthritis at baseline
| Baseline CRP <5 | Baseline CRP ⩾5 | Peripheral arthritis absent | Peripheral arthritis present | |||||||||
| TNF(n = 16) | Placebo(n = 20) | SMD | TNF(n = 70) | Placebo(n = 71) | SMD | TNF(n = 49) | Placebo(n = 56) | SMD | TNF(n = 37) | Placebo(n = 35) | SMD | |
| Back pain, morning stiffness, patient global, ESR, CRP | −0.91 (0.74) | 0.10 (0.44) | 1.77 | −2.23 (1.33) | −0.41 (0.85) | 1.67 | −1.91 (1.30) | −0.30 (0.76) | 1.59 | −2.07 (1.41) | −0.29 (0.88) | 1.55 |
| Back pain, morning stiffness, patient global, pain/swelling peripheral, ESR | −1.01 (0.58) | 0.00 (0.44) | 2.01 | −1.97 (1.24) | −0.35 (0.88) | 1.53 | −1.71 (1.20) | −0.26 (0.76) | 1.50 | −1.91 (1.22) | −0.30 (0.91) | 1.50 |
| Back pain, morning stiffness, patient global, pain/swelling peripheral, CRP | −0.99 (0.92) | 0.06 (0.48) | 1.55 | −2.12 (1.30) | −0.46 (0.82) | 1.57 | −1.83 (1.29) | −0.34 (0.75) | 1.49 | −2.01 (1.35) | −0.36 (0.86) | 1.49 |
| Back pain, morning stiffness, fatigue, ESR, CRP | −0.89 (0.73) | 0.11 (0.47) | 1.71 | −2.16 (1.28) | −0.40 (0.87) | 1.64 | −1.88 (1.27) | −0.28 (0.72) | 1.64 | −1.99 (1.34) | −0.30 (0.98) | 1.45 |
| BASDAI | −2.43 (1.77) | −0.33 (1.11) | 1.50 | −3.19 (2.47) | −0.78 (2.17) | 1.04 | −2.98 (2.51) | −0.64 (1.96) | 1.05 | −3.14 (2.19) | −0.75 (2.07) | 1.12 |
| BASDAI 1: fatigue | −2.25 (2.14) | −0.16 (1.86) | 1.05 | −2.48 (2.88) | −0.70 (2.22) | 0.70 | −2.35 (2.79) | −0.59 (1.91) | 0.76 | −2.54 (2.70) | −0.55 (2.51) | 0.76 |
| BASDAI 2: back pain | −2.89 (2.67) | −0.26 (1.68) | 1.24 | −3.88 (2.95) | −1.33 (2.48) | 0.94 | −3.83 (3.03) | −1.12 (2.46) | 0.99 | −3.44 (2.73) | −1.02 (2.21) | 0.98 |
| BASDAI 3: pain/swelling peripheral joints | −2.61 (1.72) | −0.29 (2.15) | 1.18 | −2.62 (3.32) | −0.73 (3.53) | 0.55 | −2.32 (2.98) | −0.43 (3.60) | 0.57 | −3.06 (3.14) | −0.95 (2.61) | 0.73 |
| BASDAI 4: enthesitis | −1.94 (2.35) | −0.33 (2.22) | 0.71 | −3.22 (3.34) | −0.69 (3.29) | 0.76 | −2.82 (3.14) | −0.62 (3.44) | 0.67 | −3.15 (3.31) | −0.60 (2.38) | 0.89 |
| BASDAI 5: severity morning stiffness | −3.09 (2.66) | −0.78 (1.44) | 1.17 | −4.00 (3.12) | −1.09 (2.59) | 1.02 | −3.92 (3.16) | −1.23 (2.44) | 0.97 | −3.65 (2.87) | −0.67 (2.25) | 1.16 |
| BASDAI 6: duration morning stiffness | −1.77 (1.48) | −0.66 (1.79) | 0.67 | −3.11 (3.04) | −0.96 (2.00) | 0.85 | −3.12 (2.93) | −0.88 (2.07) | 0.91 | −2.40 (2.67) | −0.90 (1.77) | 0.67 |
| BASDAI 5/6: morning stiffness | −2.43 (1.80) | −0.72 (1.23) | 1.15 | −3.55 (2.86) | −1.03 (1.92) | 1.05 | −3.52 (2.81) | −1.06 (1.98) | 1.04 | −3.02 (2.55) | −0.79 (1.86) | 1.01 |
| Patient global | −2.58 (2.35) | −0.32 (1.72) | 1.13 | −3.78 (2.95) | −0.90 (2.38) | 1.08 | −3.40 (2.93) | −0.78 (2.44) | 0.98 | −3.76 (2.83) | −0.77 (1.97) | 1.24 |
| Physician global | −2.46 (1.97) | −0.53 (1.28) | 1.22 | −3.73 (2.39) | −0.96 (2.04) | 1.25 | −3.20 (2.41) | −0.61 (1.86) | 1.22 | −3.89 (2.29) | −1.27 (1.93) | 1.24 |
| ESR | −3.6 (6.6) | 3.4 (6.5) | 1.07 | −24.7 (21.0) | −1.9 (14.8) | 1.27 | −18.2 (19.0) | −0.90 (13.1) | 1.09 | −24.3 (22.9) | −0.6 (14.4) | 1.26 |
| CRP | 1.8 (10.2) | 1.9 (4.0) | 0.01 | −22.4 (25.0) | −4.2 (12.7) | 0.97 | −15.7 (24.7) | −3.70 (12.0) | 0.67 | −20.9 (25.0) | −1.6 (11.2) | 1.06 |
Values shown as mean (SD).
BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; SMD, standardised mean difference; TNF, tumour necrosis factor.