Summary of findings: COX-2 NSAID compared with placebo for axial spondyloarthritis.
| Outcomes | Illustrative Comparative Risks* (95% CI) | Relative Effect, Risk Ratio (95% CI) | No. Participants, Studies | Quality of the Evidence, GRADE# | Comments | |
|---|---|---|---|---|---|---|
| Assumed Risk Placebo | Corresponding Risk Traditional NSAID | |||||
| Pain on VAS, scale 0–100 mm, higher is worse, followup: 6 weeks | The mean pain scores across control groups was 64 points** | The mean pain scores in the intervention groups was 21.7 points lower (7.4 to 35.9) | 349 (2 studies) | High | Absolute percent difference: 22% lower (7% to 36%). Relative percent change from baseline: 28% lower (10% to 47%)***. NNT: 3 (2 to 24)†. | |
| Withdrawals because of adverse events, followup: 6 to 12 weeks | 11 per 1000†† | 24 per 1000 (4 to 142) | 2.14 (0.36–12.56) | 669 (3 studies) | Low††† | Absolute percent difference: 2% more (2% less to 6% more). Relative percent difference from baseline: 114% increase (64% decrease to 1156% increase). |
| BASDAI, scale 0–100, higher is worse, followup: 6 weeks | The mean BASDAI in the control group was 54.7 points | The mean BASDAI in the intervention group was 22 points lower (16.6 to 27.4) | 193 (1 study) | Moderate‡ | Absolute percent difference: 22% lower (17% to 27%). Relative percent change from baseline: 36% lower (27% to 44%)‡‡. NNT: 2 (1 to 3)‡‡‡. | |
| BASFI, scale 0–100, higher is worse, followup: 6 weeks | The mean BASFI in the control groups was 50.0 points** | The mean BASFI in the intervention groups was 13.4 points lower (9.5 to 17.4) | 349 (2 studies) | High | Absolute percent difference: 13% lower (9% to 17%). Relative percent change from baseline: 25% lower (18% to 32%)##. NNT: 3 (2 to 4)###. | |
| BASMI, scale 0–10, higher is worse | NA | NA | NA | NA | None of the trials included in this comparison reported BASMI. | |
| Radiographic progression, mean change in mSASSS, higher is worse | NA | NA | NA | NA | None of the trials included in this comparison reported mSASSS. | |
| No. serious adverse events, followup: 6 to 12 weeks | 2 per 1000†† | 2 per 1000 (0 to 13) | 0.92 (0.14–6.21) | 669 (3 studies) | Moderate$ | Absolute percent difference: 0% more (1% less to 1% more). Relative percent change from baseline: 8% decrease (86% decrease to 512% increase). |
↵* The basis for the assumed risk (e.g., the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% CI) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).
↵# GRADE Working Group grades of evidence: high quality (further research is very unlikely to change our confidence in the estimate of effect), moderate quality (further research is likely to have an important effect on our confidence in the estimate of effect and may change the estimate), low quality (further research is very likely to have an important effect on our confidence in the estimate of effect and is likely to change the estimate), and very low quality (we are very uncertain about the estimate).
↵** Assumed risk based on the control group final values from van der Heijde, et al80.
↵*** Estimated relative changes based on mean (SD) pain on VAS in placebo group at baseline 77.22 (15.24) from van der Heijde, et al80.
↵† Based on MCID of 15 points on 0–100 point scale.
↵†† Assumed risk based on the mean risk in the control groups.
↵††† Potential imprecision because the 95% CI includes “no effect” and the upper confidence limit also crosses “appreciable harm,” as well as inconsistency in the results with large heterogeneity (I2 = 84%).
↵‡ Potential imprecision because of data available only from a single study (n = 193).
↵‡‡ Estimated relative changes based on mean (SD) BASDAI in placebo group at baseline 61.78 (18.70) from van der Heijde, et al80.
↵‡‡‡ Based on MCID of 10 points on a 0–100 point scale.
↵## Estimated relative changes based on mean (SD) BASFI in placebo group at baseline 54.12 (26.99) from van der Heijde, et al80.
↵### Based on MCID of 10 points on a 0–100 point scale.
↵$ Potential imprecision because the 95% CI includes “no effect” and the upper confidence limit also crosses “appreciable harm.” COX-2: cyclooxygenase-2; NSAID: nonsteroidal antiinflammatory drug; VAS: visual analog scale; BASDAI: Bath Ankylosing Spondylitis Disease Activity Index; BASFI: Bath Ankylosing Spondylitis Functional Index; BASMI: Bath Ankylosing Spondylitis Metrology Index; mSASSS: modified Stoke Ankylosing Spondylitis Spinal Score; NNT: number needed to treat; MCID: minimal clinically important difference; NA: not applicable; GRADE: Grading of Recommendations Assessment, Development, and Evaluation.