Investigating the association between the symptoms of women with Fibromyalgia, Digestive function, and markers of the microbiota of the Gastrointestinal Tract (The FIDGIT Study): study protocol

Abstract

Background Fibromyalgia a common idiopathic condition affecting around 1.4% of adults globally. Its signature symptom is chronic widespread pain, with a constellation of somatic and psychological symptoms. Fibromyalgia is associated with significant reductions in quality of life, yet to date there is no biochemical marker for its diagnosis. Previous studies have indicated a strong association with gastrointestinal dysfunction, and more recently, alterations to the gut microbiome. No studies have examined the inter-relationship between fibromyalgia, gastrointestinal dysfunction, and the microbiome. This prospective observational case-controlled study will gather data on gastrointestinal function, dietary intake, fermentation patterns of ingested carbohydrates, and symptoms commonly associated with fibromyalgia. These will be evaluated alongside human gene expression and metatranscriptomic analysis of the oral and faecal microbiome. Methods Adult women aged ≥18 years diagnosed with fibromyalgia and/or meeting ACR 2016 criteria, and healthy family or age-matched controls will be recruited from the community. From consenting participants, we will collect detailed survey information and samples of blood, urine, stool, saliva, and breath. Discussion This is the first prospective study examining interactions between digestive function, human gene expression, and the gut microbiome together with general, and fibromyalgia-specific, symptoms experienced by New Zealand women. This exploration will allow an in-depth understanding of clinically relevant factors that are associated with fibromyalgia and will guide further research and contribute to improved management of this poorly understood condition. Trial Registration The study was approved by the New Zealand Health and Disability Committee (HDEC) (ref: 20/CEN/197) and registered with the Australia and New Zealand Clinical Trials Registry (ANZCTR), registration number ACTRN12620001337965. Written consent will be obtained after providing participants with detailed information about the procedures. Access to data will be restricted to the immediate research team, and all samples and survey data will be deidentified and coded before analysis.

Increased gut permeability and bacterial translocation are associated with fibromyalgia and myalgic encephalomyelitis/chronic fatigue syndrome: implications for disease-related biomarker discovery

“…Future studies should also expand the use of other validated inflammatory biomarkers in stool and blood in order to fully define the specific role of disturbed intestinal barrier function and inflammation in FM and ME/CFS. These studies should also include lactulose breath testing (SIBO) by collecting longitudinal faecal samples to explore gender-dependent microbiota composition in these conditions ( 29 , 56 ).…”

“…In addition, a growing number of studies linked the increased immune activation with the alteration of the gut microbiome composition in FM and ME/CFS ( 15 , 23 , 26 – 29 ), thereby suggesting that perturbed microbiome homeostasis may induce an imbalance in tolerance induction. An intestinal barrier dysfunction characterized by increased gut permeability and microbial translocation may lead to irritable bowel syndrome (IBS), which could impair tolerance the development of tolerance and instead contribute to exacerbation of symptoms in these conditions ( 11 , 30 , 31 ).…”