Session Information
Date: Tuesday, November 7, 2017
Session Title: Fibromyalgia, Soft Tissue Disorders, Regional and Specific Clinical Pain Syndromes Poster II
Session Type: ACR Poster Session C
Session Time: 9:00AM-11:00AM
Background/Purpose:
The ACR 2010 preliminary criteria for fibromyalgia (FM) classifies patients in high WPI group, widespread pain index (WPI) ≥7, symptom severity scale (SS) ≥5, and low WPI group, WPI 3-6, SS ≥9.
It is not clear why some FM patients have less pain. Low WPI FM have lower disability scores, lower pain and global severity than high WPI group. Are there differences in the characteristics of low WPI and high WPI FM patients with regards to depressive, anxiety symptoms, pain and global FM severity and catastrophizing scores?
Methods:
Consecutive clinically diagnosed FM patients were classified in low WPI or high WPI groups, demographic and clinical data was compared. Questionnaires used: patient health questionnaire (PHQ-9), general anxiety disorder questionnaire (GAD-7), health assessment questionnaire disability index (HAQ-DI), fibromyalgia impact questionnaire (FIQ), pain disability index, pain catastrophizing scale, polysymptomatic distress scale (PSD), as the sum of WPI and SS.
Results:
Of 552 patients diagnosed clinically with FM, age 44.3 (12), 79.5% white, 85.5% female, 4% met the low WPI and 82.1% met the high WPI criteria.
Only SS, WPI and PSD, were each significantly different between low and high WPI groups (Table 1). To understand why, we looked at the individual correlations of WPI and SS (Table 2). In linear regression model, PHQ-9, GAD-7, Pain disability index, Pain catastrophizing, HAQ-DI and FIQ significantly predict WPI, F(6,98)=4.904, P<0.0001, R2 0.184; FIQ remains an independent predictor of WPI. The same model predicts SS, F(6, 98)=17.932, P<0.0001, R2 0.523; FIQ, pain catastrophizing score, PHQ-9 remain independent predictors of SS.
|
Table 1. Fibromyalgia and severity measures according to criteria categories. Values are mean (SD) unless specified. Low WPI and high WPI group are statistically significant different from each other at p <0.05 if flagged with asterisks; * p<0.05; ** P<0.001 |
|||
|
All |
WPI 3-6 and SS ≥9 |
WPI ≥7 and SS ≥ 5 |
|
|
N |
475 |
22 |
453 |
|
Age, yrs |
43.9 (11.7) |
40.9 (12.9) |
44.1 (11.6) |
|
Female, % |
86.7% |
90.9% |
86.5% |
|
Race white % |
79.8% |
81.8% |
79.7% |
|
Employed full time % |
36.4% |
36.4% |
36.4% |
|
WPI |
12.6 (3.7) |
4.6 (1.0) |
12.9 (3.4)** |
|
SS |
9.3 (1.9) |
10.4 (1.1) |
9.2 (1.9)* |
|
PSD |
21.9 (4.5) |
15 (1.4) |
22.2 (4.3)** |
|
FIQ |
60.6 (19.4) |
47.5 (13.7) |
60.9 (7.2) |
|
PHQ-9 |
13.3 (6.0) |
12.4 (5.3) |
13.3 (6.1) |
|
GAD-7 |
9.5 (7.1) |
8.8 (6.2) |
9.5 (7.2) |
|
HAQ-DI |
1.2 (1.6) |
1.2 (1.9) |
1.2 (1.5) |
|
Pain catastrophizing |
23.9 (13.2) |
20.3 (14) |
24 (13.3) |
|
Pain disability index |
5.6 (2.1) |
4.9 (2.4) |
5.7 (2.1) |
|
Table 2. WPI and SS correlations with pain disability index, FIQ, HAQ-DI, PHQ-9, GAD7 and PSD. Unless specified by * all correlations were significant at p<0.0001,* P<0.05 |
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|
WPI |
SS |
|
|
PSD |
0.911 |
0.541 |
|
SS |
0.175 |
|
|
Pain disability index |
0.301 |
0.421 |
|
FIQ |
0.352 |
0.569 |
|
HAQ-DI |
0.293 |
0.316 |
|
PHQ-9 |
0.271 |
0.516 |
|
GAD-7 |
0.170 |
0..344 |
|
Pain catastrophizing |
0.205* |
0.338 |
Conclusion:
No differences were found between high and low WPI groups, except for significantly higher PSD scores, despite many variables trending higher in the high WPI group, possibly due to the low number of patients in the low WPI group. We found that WPI and SS differ in their strength of association with core FM domains, which suggests they contribute differently to FM diagnosis.
To cite this abstract in AMA style:
Kaouk S, Kinanah Y, Jhala N, Bork D, Rispinto S, Davin S, Wilke W, Gota CE. High and Low Widespread Pain Index Fibromyalgia Patient Groups, Same, or Different? [abstract]. Arthritis Rheumatol. 2017; 69 (suppl 10). https://acrabstracts.org/abstract/high-and-low-widespread-pain-index-fibromyalgia-patient-groups-same-or-different/. Accessed January 19, 2021.« Back to 2017 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/high-and-low-widespread-pain-index-fibromyalgia-patient-groups-same-or-different/