Table 2.
Efficacy of duloxetine in treating pain in fibromyalgia patients
| Study duration | Study |
||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Arnold et al31 | Arnold et al32 | Russell et al34 | Chappell33 | Chappell et al35 | |||||||||||||
| 3 months | 6 months | 6 months | 12 months | ||||||||||||||
| Baseline demographics | |||||||||||||||||
| Percentage female | 89 | 100 | 94.8 | 93.3 | 95.7 | ||||||||||||
| Mean age (years) | 49 | 49.6 | 51 | 50.5 | 49 | ||||||||||||
| Treatment group | DLX 120 mg | PBO | DLX 60 mg | DLX 120 mg | PBO | DLX 20 mg | DLX 60 mg | DLX 120 mg | PBO | DLX 20 mg | DLX 60 mg | DLX 120 mg | PBO | DLX 60/120 mg | PBO | DLX 60 mg | DLX 120 mg |
| n | 104 | 103 | 118 | 116 | 120 | 79 | 150 | 147 | 144 | 49 | 97 | 95 | 84 | 162 | 168 | 104 | 203 |
| Outcome measure (change from baseline ± SE) | |||||||||||||||||
| FIQ total score | −13.46 (1.82) | −7.93 (1.73) | −16.72 (1.53) | −16.81 (1.54) | −8.35 (1.53) | −14.60 (1.83)* | −15.41 (1.40)* | −14.50 (1.38)* | −10.05 (1.42) | −14.77 (1.88) | −12.28 (1.44) | −13.86 (1.41) | −10.42 (1.46) | −7.96 (1.35) | −5.81 (1.29) | −0.69 (1.82) | 3.49 (1.34)* |
| Mean tender point pain threshold | 0.29 (0.07) | −0.04 (0.07) | 0.22 (0.08) | 0.39 (0.08) | 0.06 (0.08) | 0.51 (0.11) | 0.52 (0.08) | 0.42 (0.08) | 0.33 (0.08) | 0.54 (0.12) | 0.52 (0.09) | 0.54 (0.09) | 0.42 (0.09) | 0.40 (0.09) | 0.18 (0.08) | 0.58 (0.11) | 0.32 (0.08)* |
| Brief pain inventory | |||||||||||||||||
| Average pain | −1.83 (0.24) | −0.94 (0.23) | −2.39 (0.22) | −2.40 (0.22) | −1.16 (0.21) | −1.92 (0.27) | −1.99 (0.2)* | −2.31 (0.20)* | −1.39 (0.20) | −2.22 (0.28)* | −1.98 (0.21)* | −2.26 (0.21)* | −1.43 (0.21) | −1.62 (0.20) | −1.13 (0.19) | −0.37 (0.26) | −0.16 (0.19) |
| Worst pain | – | – | −2.53 (0.25) | −2.37 (0.25) | −1.35 (0.24) | – | – | – | – | – | – | − | – | −1.75 (0.22) | −1.25 (0.21) | −0.53 (0.28) | −0.18 (0.21) |
| Least pain | – | – | −1.77 (0.20) | −1.76 (0.20) | −0.58 (0.20) | – | – | – | – | – | – | – | – | −1.22 (0.19) | −0.73 (0.18) | −0.12 (0.26) | 0.21 (0.19) |
| CGI-S | −0.72 (0.12) | −0.39 (0.12) | −0.84 (0.10) | −0.84 (0.10) | −0.44 (0.10) | −0.96 (0.12) | −1.06 (0.10)* | −1.10 (0.09)* | 0.70 (0.10) | −0.97 (0.13)* | −1.07 (0.10)* | −1.14 (0.10)* | −0.66 (0.10 | −0.57 (0.09) | −0.28 (0.08) | −0.23 (0.11) | −0.04 (0.08) |
| PGI-I | 3.02 (0.17) | 3.53 (0.17) | 3.11 (1.77) | 3.06 (1.73) | 3.71 (1.5) | 2.85 (0.17)* | 3.04 (−0.13)* | 2.89 (0.13)* | 3.39 (0.13) | 2.79 (0.17)* | 3.08 (0.13) | 2.93 (0.13)* | 3.37 (0.13) | 3.43 (0.13) | 3.72 (0.12) | 2.19 (0.15) | 2.65 (0.11)* |
*
Notes: Results were statistically significant (P < 0.05) versus placebo.
Abbreviations: SE, standard error; DLX, duloxetine; PBO, placebo; FIQ, Fibromyalgia Impact Questionnaire; CGI-I, Clinical Global Impressions of Severity; PGI-I, Patient’s Global Impressions of Improvement.