. 2021 May 22;13(5):e15169. doi: 10.7759/cureus.15169

Table 3. Efficacy outcomes.

ITT = intension-to-treat; PP = per protocol; BPI-S = Brief Pain Inventory-Severity scale; avg = average; BL = baseline; SD = standard deviation; NR = not recorded; f/u = follow-up; SE = standard error; BPI-I = Brief Pain Inventory-Interference scale; PGI-S = Patient’s Global Impressions of Severity; PGI-I = Patient’s Global Impressions of Improvement; CGI-S = Clinical Global Impressions of Severity; VAS = visual analog scale; NS = not significant; SF-36 = Short Form-36; MCS = mental composite score; PCS = physical composite score; RMDQ-24 = Roland-Morris Disability Questionnaire; EQ-5D = 5-dimension EuroQoL questionnaire; WPAI = Work Productivity and Activity Impairment Instrument

*p<0.05 versus placebo

Study

Skljarevski et al. 2009

Skljarevski et al. 2010a

Skljarevski et al. 2010b

Konno et al. 2016

Shuckro et al. 2017

Groups

Duloxetine 20 mg

Duloxetine 60 mg

Duloxetine 120 mg

Placebo

Duloxetine 60-120 mg

Placebo

Duloxetine

Placebo

Duloxetine 60 mg

Placebo

Duloxetine 120 mg ITT

Placebo ITT

Duloxetine 120 mg PP

Placebo PP

60 mg

No. of Subjects

116

112

117

115

121

198

203

232

226

Duration (weeks)

BPI-S avg pain BL, mean ± SD (n)

6.3 ± 1.6 (56)

5.9 ± 1.7 (108)

6.0 ± 1.6 (108)

6.1 ± 1.7 (113)

5.9 ± 1.6 (109)

6.0 ± 1.7 (116)

5.8 ± 1.4 (195)

5.8 ± 1.4)

5.14 ± 1.11 (230)

5.09 ± 1.04 (226)

BPI-S change at final f/u, mean ± SE (n)

Average pain

-1.79 ± 0.30 (56)

-2.50 ± 0.22 (108)*

-2.45 ± 0.22 (108)

-1.87 ± 0.22 (113)

-2.08 ± 0.20 (109)

-1.30 ± 0.19 (116)

-1.65 ± 0.15 (199)

-2.43 ± 0.11 (209)*

-1.96 ± 0.11 (200)

Worst pain

-1.78 ± 0.35 (56)

-2.77 ± 0.25 (108)

-2.78 ± 0.26 (108)

-2.09 ± 0.25 (113)

-2.66 ± 0.23 (109)*

-1.90 ± 0.23 (116)

-2.56 ± 0.17 (195)*

-1.88 ± 0.17 (199)

-2.63 ± 0.13 (209)

-2.33 ± 0.13 (200)

Least pain

-1.30 ± 0.29 (56)

-2.06 ± 0.21 (108)

-2.16 ± 0.21 (108)*

-1.51 ± 0.20 (113)

-1.70 ± 0.20 (109)*

-0.86 ± 0.19 (116)

-1.51 ± 0.14 (195)*

-1.02 ± 0.14 (199)

-1.69 ± 0.10 (209)*

-1.19 ± 0.11 (200)

Pain right now

-1.63 ± 0.33 (56)

-2.67 ± 0.24 (108)

-2.61 ± 0.24 (108)*

-1.74 ± 0.24 (113)

-2.35 ± 0.24 (109)*

-1.42 ± 0.23 (116)

-2.40 ± 0.15 (195)*

-1.54 ± 0.15 (199)

-2.42 ± 0.12 (209)*

-2.03 ± 0.12 (200)

BPI-I change at final f/u, mean ± SE (n)

General activity

-1.99 ± 0.33 (56)

-2.52 ± 0.24 (107)

-2.36 ± 0.25 (108)

-1.97 ± 0.24 (113)

-2.09 ± 0.26 (109)

-1.49 ± 0.25 (115)

-2.36 ± 0.16 (195)*

-1.61 ± 0.16 (199)

-2.46 ± 0.13 (209)

-2.16 ± 0.13 (200)

Mood

-1.75 ± 0.30 (56)

-2.52 ± 0.22 (107)*

-1.96 ± 0.22 (108)

-1.70 ± 0.21 (113)

-1.87 ± 0.27 (109)*

-0.96 ± 0.26 (115)

-1.98 ± 0.15 (195)*

-1.26 ± 0.15 (199)

-2.15 ± 0.11 (209)*

-1.83 ± 0.11 (200)

Walking ability

-1.79 ± 0.34 (56)

-2.33 ± 0.25 (107)*

-1.89 ± 0.25 (108)

-1.43 ± 0.24 (113)

-2.04 ± 0.25 (109)*

-1.16 ± 0.24 (115)

-1.86 ± 0.15 (195)*

-1.40 ± 0.15 (199)

-2.05 ± 0.11 (209)

-1.92 ± 0.11 (200)

Normal work

-2.20 ± 0.36 (56)

-2.67 ± 0.26 (107)*

-2.38 ± 0.26 (108)

-1.95 ± 0.26 (113)

-2.25 ± 0.26 (109)*

-1.50 ± 0.25 (115)

-2.17 ± 0.15 (195)*

-1.66 ± 0.15 (199)

-2.17 ± 0.12 (209)

-2.17 ± 0.12 (200)

Relations with other people

-1.33 ± 0.27 (56)

-1.86 ± 0.20 (107)*

-1.27 ± 0.20 (108)

-0.94 ± 0.19 (113)

-1.59 ± 0.22 (109)*

-0.78 ± 0.22 (115)

-1.48 ± 0.15 (195)*

0.91 ± 0.14 (199)

-1.02 ± 0.10 (209)

-0.98 ± 0.10 (200)

Sleep

-1.59 ± 0.32 (56)

-2.48 ± 0.24 (107)*

-2.12 ± 0.24 (108)

-1.63 ± 0.23 (113)

-1.95 ± 0.26 (109)

-1.31 ± 0.25 (115)

-2.14 ± 0.17 (195)*

-1.45 ± 0.17 (199)

-1.41 ± 0.11 (209)

-1.40 ± 0.11 (200)

Enjoyment of life

-1.84 ± 0.32 (56)

-2.49 ± 0.24 (107)*

-1.86 ± 0.24 (108)

-1.76 ± 0.23 (113)

-1.74 ± 0.25 (109)*

-0.94 ± 0.24 (115)

-2.18 ± 0.15 (195)*

-1.61 ± 0.15 (199)

-1.52 ± 0.11 (209)

-1.48 ± 0.11 (200)

Avg of 7 questions

-1.84 ± 0.26 (56)

-2.40 ± 0.19 (107)*

-1.92 ± 0.19 (108)

-1.61 ± 0.16 (113)

-1.92 ± 0.21 (109)*

-1.18 ± 0.20 (115)

-2.01 ± 0.13 (195)*

-1.43 ± 0.13 (199)

-1.83 ± 0.10 (209)

-1.70 ± 0.10 (200)

PGI-S at BL, mean ± SD

2.8 ± 1.7 (59)

2.6 ± 1.8 (116)

2.3 ± 1.6 (108)

2.4 ± 1.6 (117)

PGI-I at final f/u, mean ± SE (n)

2.71 (54)

2.43 (102)

2.65 (101)

2.92 (108)

2.59 (109)*

3.16 (115)

2.88 ± 0.09 (194)*

3.19 ± 0.09 (199)

2.46 ± 0.07 (209)*

2.76 ± 0.07 (200)

CGI-S at BL, mean ± SD

4.1 ± 1.4 (59)

3.5 ± 1.5 (116)

3.6 ± 1.3 (112)

3.7 ± 1.3 (117)

3.2 ± 1.5 (115)

3.2 ± 1.5 (121)

3.5 ± 1.2 (198)

3.3 ± 1.3 (203)

4.23 ± 0.66 (230)

4.22 ± 0.71 (226)

CGI-S change at final f/u, mean ± SE (n)

-0.53 ± 0.14 (58)

-0.94 ± 0.11 (108)*

-1.06 ± 0.11 (107)*

-0.53 ± 0.10 (112)

-0.98 ± 0.10 (110)

-0.77 ± 0.10 (117)

-0.95 ± 0.07 (195)

-0.79 ± 0.07 (199)

-1.46 ± 0.06 (209)*

-1.17 ± 0.06 (200)

VAS at final f/u, mean ± SD

4.1 ± 2.9*

6.0 ± 2.7

3.7 ± 2.9*

5.7 ± 2.5

VAS change at final f/u, mean ± SD

-2.7 ± 2.5*

-0.5 ± 1.6

painDETECT at final f/u, mean ± SD

17.7 ± 5.7*

21.3 ± 3.6

Athens Insomnia Scale change at final f/u, mean ± SE (n)

-1.43 ± 0.53 (54)

-2.30 ± 0.39 (101)*

-0.93 ± 0.40 (99)

-1.23 ± 0.38 (107)

-2.07 ± 0.047 (104)

-1.49 ± 0.47 (106)

SF-36 change at final f/u, mean ± SE (n)

Bodily pain

1.51 ± 0.27 (54)

1.95 ± 0.20 (102)*

2.11 ± 0.20 (101)*

1.36 ± 0.19 (108)

1.58 (109)*

1.04 (115)

16.28 ± 1.45 (188)*

11.70 ± 1.44 (190)

12.56 ± 0.94 (230)

11.01 ± 0.95 (226)

General health

0.70 ± 0.41 (54)

1.24 ± 0.30 (102)

0.81 ± 0.30 (101)

0.66 ± 0.29 (108)

1.90 (109)*

0.87 (115)

6.96 ± 1.20 (188)

4.38 ± 1.20 (190)

6.72 ± 0.85 (230)*

3.78 ± 0.86 (226)

Mental health

0.21 ± 0.49 (54)

0.98 ± 0.36 (102)

0.46 ± 0.36 (101)

0.38 ± 0.35 (108)

5.83 ± 1.07 (165)*

0.95 ± 1.07 (166)

5.63 ± 0.81 (230)*

2.42 ± 0.82 (226)

Physical functioning

1.80 ± 0.52 (54)

2.55 ± 0.38 (102)

3.11 ± 0.38 (101)

2.23 ± 0.37 (108)

11.67 ± 1.40 (186)

8.18 ± 1.41 (189)

8.47 ± 0.79 (230)

7.20 ± 0.80 (226)

Role-emotional

0.10 ± 0.12 (54)

0.19 ± 0.09 (102)

0.14 ± 0.09 (101)

0.08 ± 0.09 (108)

6.81 ± 1.77 (172)

4.39 ± 1.76 (179)

5.78 ± 1.13 (230)

6.18 ± 1.14 (226)

Role-physical

0.81 ± 0.21 (54)

0.80 ± 0.15 (102)

0.85 ± 0.15 (101)

0.80 ± 0.15 (108)

10.03 ± 1.93 (172)

8.12 ± 1.92 (179)

10.58 ± 1.15 (230)

10.00 ± 1.16 (226)

Social functioning

0.75 ± 0.21 (54)

0.46 ± 0.16 (102)

0.38 ± 0.16 (101)

0.50 ± 0.15 (108)

11.50 ± 1.40 (188)*

7.51 ± 1.40 (190)

6.40 ± 1.00 (230)

4.77 ± 1.01 (226)

Vitality

0.69 ± 0.50 (54)

1.43 ± 0.36 (102)

0.44 ± 0.37 (101)

0.91 ± 0.35 (108)

1.46 (109)*

0.43 (115)

8.73 ± 1.36 (163)*

4.63 ± 1.35 (165)

5.56 ± 0.97 (230)

4.41 ± 0.97 (226)

SF-36 MCS at final f/u, mean ± SD (n)

50.0 ± 11.6*

46.5 ± 12.5

SF-36 PCS at final f/u, mean ± SD (n)

36.0 ± 10.9*

31.3 ± 9.3

RMDQ-24 change at f/u, mean ± SE (n)

-2.28 (54)

-2.74 (102)*

-2.88 (101)*

-1.33 (108)

-3.60 (109)*

-1.93 (115)

-2.69 ± 0.31 (178)

-2.22 ± 0.32 (179)

-3.86 ± 0.22 (230)*

-3.23 ± 0.22 (226)

EQ-5D change at final f/u, mean ± SE (n)

0.07 ± 0.03 (54)

0.11 ± 0.02 (102)

0.13 ± 0.02 (100)

0.08 ± 0.02 (104)

0.15 ± 0.02 (190)*

0.07 ± 0.02 (192)

0.09 ± 0.01 (230)

0.08 ± 0.01 (226)

WPAI change at final f/u, mean ± SE (n)

Work time missed

0.0 ± 0.0 (79)

-0.01 ± 0.02 (93)

-0.01 ± 0.01 (140)*

0.02 ± 0.01 (143)

Impairment at work

-0.19 ± 0.03 (79)

-0.16 ± 0.02 (90)

-0.13 ± 0.02 (140)

-0.09 ± 0.02 (143)

Work productivity loss

-0.18 ± 0.03 (77)

-0.16 ± 0.03 (89)

-0.13 ± 0.02 (140)

-0.09 ± 0.02 (143)

Work activity impairment

-0.20 ± 0.02 (190)*

-0.15 ± 0.02 (196)

-0.14 ± 0.01 (230)

-0.12 ± 0.01 (226)

Global Impression of Improvement, n (%)

Improved

191 (83.0)*

163 (72.1)

Unchanged

34 (14.8)*

59 (26.1)

Worsened

5 (2.2)

4 (1.8)