Predictors of new onsets of irritable bowel syndrome, chronic fatigue syndrome and fibromyalgia: the lifelines study.
Monden, Rei, Rosmalen, Judith G M, Wardenaar, Klaas J et al. · Psychological medicine · 2022 · DOI
Quick Summary
This large Dutch study followed over 152,000 people for an average of 2.4 years to identify what factors predict who develops ME/CFS, fibromyalgia, or irritable bowel syndrome. While these conditions are often grouped together, the researchers found that each syndrome had mostly different predictors, suggesting they may develop through different biological or psychological pathways rather than sharing one common cause.
Why It Matters
For ME/CFS patients and researchers, this study challenges the assumption that these functional syndromes stem from a single cause, potentially redirecting research toward condition-specific mechanisms. Understanding distinct risk factors for ME/CFS could lead to more targeted prevention and treatment strategies rather than applying one-size-fits-all approaches.
Observed Findings
Only 1,595 (1.2%) new cases of IBS, 296 (0.2%) of ME/CFS, and 692 (0.5%) of FM developed during 2.4 years of follow-up.
LASSO analysis identified 26 predictors for IBS, 7 for ME/CFS, and 19 for FM.
Four predictors were shared by all three syndromes; 28 predictors were unique to a single syndrome.
IBS and FM had a closer relationship, predicting each other, while CFS was more distinct from both.
Inferred Conclusions
These functional somatic syndromes do not share a universal common etiology but rather have heterogeneous etiologies with both syndrome-specific and limited shared risk factors.
Syndrome-specific predictors should become the focus of future research rather than approaches based on shared symptom patterns.
The strong relationship between IBS and FM suggests these conditions may share more overlapping mechanisms than either shares with ME/CFS.
Remaining Questions
What are the biological mechanisms underlying the syndrome-specific predictors identified for ME/CFS, and how do they differ from IBS and FM mechanisms?
Why is ME/CFS more distinct from IBS and FM, and what explains the particularly close relationship between IBS and FM?
Can these predictors be validated in other populations with objective diagnostic criteria rather than self-report?
What This Study Does Not Prove
This study does not prove that ME/CFS, IBS, and fibromyalgia have completely separate causes—shared predictors do exist for all three. The findings are correlational and cannot establish causation. Additionally, reliance on self-reported diagnoses without clinical confirmation may have affected the accuracy of syndrome classification.
Tags
Symptom:PainFatigue
Method Flag:PEM Not DefinedWeak Case DefinitionExploratory OnlyMixed Cohort