Skip to main content

Table 6 Nonclustering variables, including medication use, compared across clusters in external sample a

From: OMERACT-based fibromyalgia symptom subgroups: an exploratory cluster analysis

Variables

Cluster 1b(n = 116)

Cluster 2c(n = 154)

Cluster 3d(n = 100)

Cluster 4e(n = 108)

P-valuef

Age, yr

49.3 (15.2)

47.4 (13.2)

45.1 (12.1)

43.7 (10.9)

0.0074

BMI, kg/m2

29.1 (6.7)

31.3 (8.5)

29.7 (8.3)

30.3 (7.2)

0.14

FM research survey

     

WPI

12.1 (3.6)

13.2 (3.7)

12.9 (3.6)

14.3 (3.3)

<0.0001

SS

7.1 (1.7)

8.1 (1.7)

9.3 (1.5)

9.6 (1.5)

<0.0001

SF-36

     

Physicalg

36.3 (7.4)

26.2 (7.0)

31.7 (6.8)

24.6 (5.7)

<0.0001

Mentalg

45.0 (10.6)

42.6 (10.2)

29.7 (9.8)

31.6 (9.8)

<0.0001

FIQ total

37.9 (10.7)

61.3 (10.8)

62.4 (9.2)

79.3 (7.9)

<0.0001

Medications

     

SNRI

26 (22.4)

37 (24.0)

34 (34.0)

48 (44.4)

0.0007

TCA

12 (10.3)

20 (13.0)

14 (14.0)

10 (9.3)

0.66

α-2-δ ligand

23 (19.8)

44 (28.6)

24 (24.0)

32 (29.6)

0.29

SSRI

22 (19.0)

36 (23.4)

29 (29.0)

26 (24.1)

0.39

Othersh

17 (14.7)

18 (11.7)

23 (23.0)

18 (16.7)

0.11

Any medication that could be used to treat depression (above)

72 (62.1)

105 (68.2)

76 (76.0)

83 (76.9)

0.0488

Tramadol

12 (10.3)

22 (14.3)

15 (15.0)

20 (18.5)

0.38

Skeletal muscle relaxants

20 (17.2)

43 (27.9)

24 (24.0)

33 (30.6)

0.10

Opioids

21 (18.1)

51 (33.1)

28 (28.0)

57 (52.8)

<0.0001

Benzodiazepines

22 (19.0)

32 (20.8)

49 (49.0)

48 (44.4)

<0.0001

Sleep aids

26 (22.4)

48 (31.2)

30 (30.0)

39 (36.1)

0.16

Total number of medications, mean (±SD)

1.9 (1.6)

2.5 (1.9)

3.1 (2.1)

3.4 (2.0)

<0.0001

Use of one or more symptom-modifying medication

92 (79.3)

131 (85.1)

89 (89.0)

100 (92.6)

0.0272

  1. aN = 478 total external sample. Data are n (%). BMI, Body mass index; FIQ, Fibromyalgia Impact Questionnaire; FM, Fibromyalgia; SF-36, Medical Outcomes Study 36-item Short Form survey; SNRI, Serotonin norepinephrine reuptake inhibitor; SS, Symptom severity (SS); SSRI, Selective serotonin reuptake inhibitor; TCA, Tricyclic antidepressant; WPI, Widespread pain index. bLow symptom intensity. cModerate symptoms, low negative mood. dModerate symptoms, higher negative mood and dyscognition. eHigh symptom intensity. fP-values are from the omnibus analysis of variance test across the four clusters. . gLower scores are worse for these scales. hIncludes other antidepressants, such as lithium, monoamine oxidase inhibitors, antipsychotics, bupropion, buspirone, lamotrigine and tetracyclic antidepressants.