Table 5: Subgroup analysis-comparison of baseline and follow-up outcomes among pain improvement subgroup* and remaining sample.
| Patient-reported Outcome, mean (SD) |
Baseline |
Follow-up |
Mean Change (95% CI) |
P value |
| BPI-SF Pain Severity Index†
|
| ≥2pt improvement |
5.6 (1.3) |
3.1 (1.8) |
-2.43 (-3.26, -1.61) |
<0.001 |
| <2pt improvement |
5.2 (2.0) |
5.5 (2.1) |
0.25 (-0.06, 0.55) |
0.111 |
| BPI-SF Pain Interference Index†
|
| ≥2pt improvement |
6.8 (1.7) |
3.4 (2.4) |
-3.35 (-4.89, -1.81) |
0.001 |
| <2pt improvement |
5.7 (2.5) |
5.6 (2.3) |
-0.12 (-0.52, 0.29) |
0.568 |
| WPAI Activity Impairment†
|
| ≥2pt improvement |
59.1 (25.9) |
50.0 (23.2) |
-9.09 (-31.86, 13.68) |
0.395 |
| <2pt improvement |
58.3 (24.9) |
61.2 (27.5) |
2.33 (-2.14, 6.80) |
0.301 |
| MOS-SS Overall Sleep Problems Index†
|
| ≥2pt improvement |
62.4 (13.9) |
51.0 (17.5) |
-11.41 (-23.49, 0.66) |
0.061 |
| <2pt improvement |
57.6 (16.0) |
53.0 (16.4) |
-4.15 (-7.78, -0.51) |
0.026 |
| EQ-5D |
| ≥2pt improvement |
0.59 (0.21) |
0.68 (0.20) |
0.09 (-0.05, 0.24) |
0.189 |
| <2pt improvement |
0.64 (0.19) |
0.65 (0.19) |
0.02 (-0.03, 0.06) |
0.518 |
| SF-12 Physical Component Summary†
|
| ≥2pt improvement |
37.0 (8.3) |
38.6 (8.0) |
1.67 (-3.75, 7.09) |
0.508 |
| <2pt improvement |
32.1 (11.1) |
33.3 (11.3) |
1.51 (-0.41, 3.43) |
0.121 |
Abbreviations: BPI-SF, Brief Pain Inventory-Short Form; EQ-5D, EuroQol 5 dimensions, 3 levels; MOS-SS, Medical Outcomes Study-Sleep Scale; pt, point; SD, standard deviation; SF-12, 12-item Short-Form Health Survey; WPAI, Work Productivity and Activity Impairment scale.
*These patients experienced clinically meaningful (i.e., at least 2.0 points) improvement in average pain severity over the past 7 days between Baseline and Follow-up assessments.
†A total of 76 fibromyalgia patients (11 with ≥2 point improvement, 65 with <2 point improvement) attended the site visit at Follow-up, but 5 patients in the subgroup with <2 point improvement did not complete the patient questionnaire following the site visit.