Perceived Stressed Associated With Symptom Burden in People With Fibromyalgia

Perceived stress was positively correlated with symptom burden in people with fibromyalgia syndrome even when not correlated with endocrinological stress indicators, according to new research.1

“As chronic stress-associated conditions and chronic pain have been associated with a suppression of hypothalamic-pituitary-adrenal (HPA)-activity, we postulate that people with FMS will have subjectively elevated stress levels compared to pain-free controls, with reduced HPA-axis activity, basal cortisol levels and hair cortisol levels. We also expect that more severe and more pronounced symptoms of FMS will result in higher subjective levels of stress and higher acute levels of salivary cortisol,” lead investigator Eva Beiner, PhD, Department of General Internal Medicine and Psychosomatics, Heidelberg University, Heidelberg, Germany, and colleagues wrote.1

Beiner and colleagues conducted a comparative study with 99 participants with FMS and a control group of 50 pain-free participants. They classified stress indicators into 3 categories: perceived stress assessed using the Perceived Stress Scale, and daily average salivary cortisol and hair cortisol concentrations as related HPA indicators of acute and chronic stress levels. They used analysis of variance and covariance to identify group differences and the influence of covariates age, sex, and body mass index and correlational analyses to further analyze the relationship between stress indicators and clinical symptoms.

The investigators found that participants with FMS reported significantly higher perceived stress levels than controls (P <.001, ηp2 = 0.3), which were positively correlated with symptom burden (r = .41, P <.001). They did not find any significant differences in the endocrinological stress indicators salivary and hair cortisol between the groups (P >.05), and these indicators were not associated with clinical symptoms.1

“In our study of FMS individuals and pain-free controls, individuals with FMS reported significantly higher subjective stress levels, closely related to symptom severity. Importantly, a dissociation between perceived stress and cortisol indicators of stress was observed. We found no evidence linking FMS to HPA axis-related markers of acute and chronic stress levels like cortisol concentrations in saliva or hair. This underscores the need for nuanced clinical approaches that target perceived stress in individuals with FMS to improve symptom management and to reveal the complex relationship between stress perception and physiological stress responses,” Beiner and colleagues concluded.1

Other recent research in FMS found that people with FMS had impaired bioenergetic health index (BHI), a proxy of mitochondrial function, which also had a slight correlation with pain. Lead investigator Chiara Macchi, MD, Department of Pharmacological and Biomolecular Sciences “Rodolfo Paoletti”, Università Degli Studi di Milano, Milan, Italy, and colleagues studied mitochondrial dysfunction in peripheral blood mononuclear cells isolated from 50 patients with primary FMS and 20 apparently healthy controls. They did not find any differences in mitochondrial basal respiration between patients with primary FMS and healthy controls, but they did find that people with FMA had a lower median BHI (−22.1%, P =.03) than healthy controls.2

The investigators also found patients with fibromyalgia severity scores (FSS) of at least 20 had a lower median BHI (−18.7%) compared to those with an FSS under 20. There were moderate negative moderate correlations between BHI and FSS (r = − 0.36) and widespread pain index (r = − 0.38).2

REFERENCES

1. Beiner E, Hermes M, Reichert J, et al. Perceived and endocrine acute and chronic stress indicators in fibromyalgia syndrome. Sci Rep 14, 30471 (2024). https://doi.org/10.1038/s41598-024-76635-z

2. Macchi C, Giachi A, Fichtner I, et al. Mitochondrial function in patients affected with fibromyalgia syndrome is impaired and correlates with disease severity. Sci Rep (2024): 14(30247). doi: 10.1038/s41598-024-81298-x