Serum hyaluronic acid levels do not explain morning stiffness in patients with fibromyalgia

Abstract

To investigate the serum levels of hyaluronic acid (HA) in Korean female patients with fibromyalgia (FM) and correlate these levels with variables of disease severity including morning stiffness, we measured HA serum levels in 69 FM patients, 72 rheumatoid arthritis (RA) patients, and 71 healthy controls by enzyme-linked binding protein assay. The serum levels of HA in FM patients did not differ from those in the age-matched controls, whereas HA levels were significantly higher in RA patients than in FM patients and controls (both P < 0.001). With a cut-off value of 75 ng/mL, the prevalence of seropositivity was higher in RA patients (59.7%) than in FM patients (26.1%) or controls (14.1%; both P < 0.001). There were no differences in seropositivity between FM patients and controls, or between FM patients with severe symptoms and those with mild symptoms. The HA levels in FM patients were significantly correlated with age, age at diagnosis, age at symptom development, disease duration, symptom duration, and level of education. There were no correlations between HA levels and morning stiffness, tender point counts and scores, or Fibromyalgia Impact Questionnaire, State-Trait Anxiety Inventory, and Beck Depression Inventory scores. In our patients, the serum HA levels were not increased and did not reflect disease severity. These results suggest that serum HA is not a useful laboratory marker for diagnosis and assessment of FM.

Potential role of blood biomarkers in patients with fibromyalgia: a systematic review with meta-analysis

“…In serum, 8 studies reported significantly higher levels of IL-6 among patients with FM compared with HC 14,31,41,53,58,82,86,93 and 7 studies reported significantly higher levels of IL-8 in patients with FM as well. 15,14,44,58,83,88,93 Five studies reported higher levels of CRP in serum in patients with FM, 4,15,33,64,93 whereas 3 studies found no differences. 2,67,78 Five studies reported higher levels of BDNF in FM, 22,32,51,63,75 8 studies assessed TNF-α and reported higher levels in patients with FM, 15,14,17,22,31,81,86,88 and 1 study reported higher levels of IL-10 in FM.…”

“…22,32,37,51,63,71,75 Eight studies (26%) assessed CRP in serum and one study in whole blood. 1,2,4,15,27,33,67,78,93 Six studies assessed IGH and GH, 3 in serum, and 3 in whole blood, 23,27,57,66,73,78 and 19 (45%) studies assessed different anti-inflammatory and proinflammatory immune mediators in serum, for example (IL-1 and 1B, IL-6, IL-4, IL-8, IL-10, TNF-a, and IFN-g. 3,15,14,22,31,37,41,44,54,58,61,63,71,72,82,83,86,88,93 Further details for the investigated blood biomarkers were shown in Table 2.…”

“…The most common method was ELISA; other methods included were bead-based immunoassay, radioimmunoassay, and real-time PCR. In serum, cytokine levels were investigated with ELISA in 17 studies, 15,14,31,32,37,41,44,51,53,63,68,71,75,78,82,86,93 with beadbased immunoassay in 5 studies 3,15,33,36,58,61,88 and real-time PCR in 1 study. 83 In plasma, 8 studies used ELISA 8,9,13,38,55,72,74,80 and 8 studies used bead-based immunoassay.…”

“…Twelve studies could not be included because mean and SDs were not reported or could not be calculated. 17,31,35,44,53,59,64,68,69,71,78,87 Because the meta-analyses were conducted in individual blood biomarkers, 2 studies were excluded because data of the investigated blood biomarkers were available in less than 3 studies. 7,8 As a result, 40 studies were principally considered for metaanalysis.…”

Analysis of the Influence of IL-6 and the Activation of the Jak/Stat3 Pathway in Fibromyalgia

“…Increased levels of pro-inflammatory cytokines, such as TNF-α, IL-1β and IL-6 and their mediators, were detected in the suffering animals compared to the controls, confirming the key role of inflammation in fibromyalgia [ 90 , 91 ]. Among these circulating biomarkers, calcitonin gene-related peptide (CGRP) is also dysregulated and may be a reliable parameter to help diagnose this complex syndrome [ 92 ], while there were no differences in vascular endothelial growth factor (VEGF) and nitric oxide (NO) levels between patients and controls [ 93 ]. The IL-6-R-Ab administration reduced proinflammatory cytokine levels.…”