Skip to main content

Advertisement

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.