Clin Rheumatol. 2015 Aug;34(8):1473-9.
Is it necessary to strictly diagnose fibromyalgia syndrome in patients with chronic widespread pain?
On AY, Aykanat D, Atamaz FC, Eyigor C, Kocanogullari H, Oksel F.
Department of Physical Medicine and Rehabilitation, Ege University Medical Faculty, Izmir, Turkey.
The applicability of the American College of Rheumatology (ACR) 1990 and 2010 criteria for the diagnosis of fibromyalgia syndrome (FMS) was determined in 284 patients with chronic widespread pain (CWP) including those with regional and systemic painful disorders. On the basis of initial evaluation, patients were classified into three groups. Group 1, those without any comorbid disease (N = 105), group 2, those having regional non-inflammatory painful disorders (N = 104), and group 3, those with a diagnosis of an inflammatory rheumatic disease (N = 75). Overall, 65 % of the patients fulfilled the 1990 criteria, while 94 % of them fulfilled the 2010 criteria. Almost all of the patients (97 %) with CWP did meet at least one of the criteria set, regardless of whether they have accompanying painful disorders. Widespread pain index (WPI), symptom severity scale (SS), and fibromyalgia impact questionnaire (FIQ) scores were found to be significantly higher in the patients who satisfied the 1990 criteria than those who did not (P < 0.001). Tender point counts were found to be significantly correlated with WPI, SS, FIQ, and Beck depression inventory (BDI) scores (P < 0.001). The findings of the study support the suggestion that FMS is just a continuum of CWP, rather than a distinct diagnostic entity. As treatment of FMS is usually identical with that of CWP, strict diagnosis of FMS will provide little or no significance from the viewpoint of clinical practice. We suggest that future research should be directed toward classification of CWP to provide guidance to clinicians in selecting effective therapies.
Chronic widespread pain (CWP) affecting musculoskeletal system has been known for several centuries and various terms have been used to describe pain conditions that are unexplained by organic cause. Fibromyalgia syndrome (FMS) is one of them, which is characterized by the presence of CWP and variety of somatic symptoms. Although several criteria have been developed in an attempt to clarify FMS, they all have some limitations in differentiating a FMS patient from among a broad spectrum of patients with CWP. An important question that still needs to be determined is whether FMS is just the extreme part of a spectrum of CWP rather than a separate clinical disorder. More importantly, there has been a confliction between the current criteria regarding the exclusion of a disorder that would otherwise explain the pain. Another important consideration for these criteria is that, although CWP has been the core feature of FM in all currently available criteria sets, these criteria have not been tested in patients who have already had CWP.
In order to address these ambiguous aspects of currently available criteria, we aimed to investigate the fulfillment of the American College of Rheumatology (ACR) 1990 (1) and 2010 criteria (2) for FMS in 284 patients representing with CWP, including those with regional painful disorders and systemic inflammatory diseases. (3) We found that 97% of the patients with CWP satisfied at least one of the criteria set regardless of whether they have accompanying painful disorders. Moreover, the severity of the symptoms assessed in the 2010 criteria was similar in three groups, supporting the fact that these symptoms may be seen in most patients with CWP, rather than FMS-specific symptoms. These finding might reflect that almost all the patients with CWP would be diagnosed as FMS by using the clinical criteria or that FMS is not a distinct diagnostic entity.
We also found that many patients that would not satisfy the TP criterion of the 1990 criteria may be diagnosed as FMS by using the 2010 criteria. Then we asked the question… are the patients who satisfied the ACR 1990 TP criterion really clinically distinct from those with CWP who do not meet that criterion? We found that TP counts were associated with greater symptom severity and depression and the patients who had satisfied the TP criterion of the ACR 1990 had more severe symptoms comparing to those who had not. This finding suggested that assessing the number of TPs in patients with CWP is still important, as they may represent increased pain sensitivity and more severe end of the spectrum of CWP.
Another important aspect of the study was that we applied both FMS criteria in a group of patients with inflammatory arthritis who had CWP, despite the exclusionary regulation of the 2010 criteria. We found that 69% of the patients met the 1990 criteria, and of the remaining patients 92% were diagnosed as FMS by using the 2010 criteria. This finding was very important as it reflects that many patients who had CWP and associated symptoms may remain unrecognized if we use only 1990 criteria, which may cause overestimation of disease activity and inadequate treatment.
With these findings, we came to the conclusion that distinction of FMS in the clinical context of CWP seems to be not useful from the viewpoint of clinical practice, because of their similar pattern of clinical presentation and commonality of central sensitization to their pathophysiology in the absence of definitive objective confirmation. Based on these considerations we also claimed that such a distinction will not make a significant difference in the management plan as they will response similarly to centrally acting treatments. We have added more detailed discussion about this statement in a respective paper, specifically addressing the clinical implications of central sensitization phenomenon for the diagnosis and treatment of FMS and other chronic pain disorders. (4) After having reviewed the recent advances in the pain field we suggested that an effective treatment in an individual patient should be tailored according to the pain characteristics and dominant underlying mechanisms responsible for pain rather than the specific diagnosis the patient is suffering.
The importance of this study: To the best of our knowledge, this was the first study comparing both criteria in the patients who had CWP and applying these criteria in a group of patients with inflammatory arthritis who had CWP. This paper seems to strongly support the arguments against FMS as a separate disorder and may serve as the starting point for future attempts to classify CWP for identifying the subsets of patients for patient centered mechanism-based management of pain.
- Wolfe F, Smythe HA, Yunus MB, Bennett RM, Bombardier C, Goldenberg DL, et al. The American College of Rheumatology 1990 criteria for the classification of fibromyalgia. Report of the multicenter criteria committee. Arthritis Rheum 1990; 33:160-172.
- Wolfe F, Clauw DJ, Fitzcharles MA, Goldenberg DL, Katz RS, Mease P, et al. The American College of Rheumatology preliminary diagnostic criteria for fibromyalgia and measurement of symptom severity. Arthritis Care Res 2010; 62:600–610
- On AY, Aykanat D, Atamaz FC, Eyigor C, Kocanogullari H, Oksel F. Is it necessary to strictly diagnose fibromyalgia syndrome in patients with chronic widespread pain? Clin Rheumatol 2015; 34:1473-1479.
- On AY. Fibromyalgia or chronic widespread pain: Does it matter? Itch Pain 2016; 3: e1079.
Arzu Yagiz On, MD,
Ege University Medical Faculty
Department of Physical Medicine and Rehabilitation
Bornova, Izmir, Turkey