Stress, Inflammation and Pain: A Potential Role for Monocytes in Fibromyalgia-related Symptom Severity

Abstract

The possibility that immunological changes might contribute to symptom severity in fibromyalgia (FM) prompted this proof-of-concept study to determine whether differences in monocyte subpopulations might be present in persons with FM compared with healthy controls. Relationships were assessed by comparing specific symptoms in those with FM (n = 20) and patterns of monocyte subpopulations with healthy age-matched and gender-matched controls (n = 20). Within the same time frame, all participants provided a blood sample and completed measures related to pain, fatigue, sleep disturbances, perceived stress, positive and negative affect and depressed mood (and the Fibromyalgia Impact Questionnaire for those with FM). Monocyte subpopulations were assessed using flow cytometry. No differences were observed in total percentages of circulating monocytes between the groups; however, pain was inversely correlated with percentages of circulating classical (r = -0.568, p = 0.011) and intermediate (r = -0.511, p = 0.025) monocytes in the FM group. Stress and pain were highly correlated (r = 0.608, p = 0.004) in the FM group. The emerging pattern of changes in the percentages of circulating monocyte subpopulations concomitant with higher ratings of perceived pain and the correlation between stress and pain found in the FM group warrant further investigation. Copyright © 2015 John Wiley & Sons, Ltd.

Perspectives on Living With Fibromyalgia

“…The stress hormones that were released affect virtually all cells and tissues in their bodies, giving rise to the symptoms the participants experienced. However, given that some people can generate and experience psychological stress in the absence of external stressors, the resulting physiological stress response can have the same deleterious effects, including significant effects on immune cell distribution and function (described in Taylor et al, 2015). …”

“…Although the authors collected data for both the quantitative and qualitative arms of the study during the same study visit, the data were analyzed and published separately. One component of quantitative data (reported in Taylor et al, 2015) was the Fibromyalgia Impact Questionnaire (FIQ) scores that are included here to provide the reader a gauge of impairment of the participants’ functional status and their perceived health-related quality of life (Bennett, 2005; Burckhardt, Clark, & Bennett, 1991). …”

Correlation of hematological indices and ratios derived from them with FIQR scores in fibromyalgia

“… 18 A recent study included twenty FM patients and showed that there is a significant role of the monocytes in mediating the pain. 2 The platelet activity is increased in FM indicating there is activity of inflammation, and the patients are at risk of coronary artery disease. The results of this study are in agreement with Haliloğlu 6 who found significant high mean platelet volume and suggested that the patients are at risk of cardiovascular disease.…”

“…Sample size = 1 + 2C (Standard deviation/difference between means) 2 , where C represents the Constant value that derived from the statistical tables and it equals to 7.85 when the 1-β =0.8 and α=0.05. Because fibromyalgia is more common in women than men.…”

“… 1 Circulating monocytes as a marker of inflammation was assessed in FM patients, and it has been found that the total percentages of circulating monocytes subpopulation not significantly differed between FM patients and healthy subjects. 2 Long standing fibromyalgia patients have increased plasma levels of cytokines including, interleukins (1L-1β, IL-4,IL-5, IL-6, IL-12, and IL-15), interferon (IFN)-α, and Tumor Necrosis Factor (TNF)-α. 3 A study has documented that there is no significant fluctuation in the serum levels of proinflammatory cytokines including, IL-6, IL-8, and TNF-α while the anti-inflammatory IL-10 level significantly increased.…”