Hand Grip Strength as a Clinical Biomarker for ME/CFS and Disease Severity.
Nacul, Luis Carlos, Mudie, Kathleen, Kingdon, Caroline C et al. · Frontiers in neurology · 2018 · DOI
Quick Summary
Researchers tested whether hand grip strength could be a useful tool for diagnosing ME/CFS and measuring how severe the condition is. They found that people with ME/CFS—especially those with severe disease—have noticeably weaker grip strength compared to healthy people, and their grip strength drops more across repeated tests. This simple, objective test may help doctors better diagnose ME/CFS and track how patients are doing over time.
Why It Matters
ME/CFS diagnosis currently relies heavily on subjective clinical history, which can be inconsistent and delay diagnosis. This study provides evidence that hand grip strength—a simple, objective, low-cost measurement—could improve diagnostic accuracy and help identify disease severity, potentially enabling earlier recognition and better monitoring of treatment response. Establishing objective biomarkers is critical for both research and clinical practice to reduce diagnostic uncertainty.
Observed Findings
Severely affected ME/CFS patients had 15.3 kg lower minimum grip strength than healthy controls (95% CI 19.3–11.3, p<0.001); mild/moderately affected patients had 10.5 kg lower grip strength (95% CI 13.2–7.8, p<0.001).
Grip strength correlated significantly with fatigue analog scale (Spearman's ρ = -0.40, p<0.001) and pain analog scale (ρ = -0.38, p<0.001).
ME/CFS patients showed greater drops in grip strength across consecutive trials compared to other groups, suggesting fatigue-related weakness.
Associations persisted after adjusting for age, sex, and body mass index.
Inferred Conclusions
Hand grip strength is a potential diagnostic biomarker for ME/CFS, with stronger associations in severely affected than mildly/moderately affected patients.
HGS reductions likely reflect both muscle weakness and fatigue-related dysfunction in ME/CFS.
HGS could be used as an objective outcome measure in future clinical trials and treatment monitoring.
HGS may enhance patient phenotyping and help differentiate ME/CFS from other chronic fatigue conditions.
Remaining Questions
What grip strength thresholds would optimally distinguish ME/CFS from other conditions in clinical practice?
What This Study Does Not Prove
This study does not prove that reduced grip strength causes ME/CFS or is the mechanism behind fatigue; it only demonstrates an association. The cross-sectional design cannot establish whether grip strength changes precede or follow ME/CFS onset. The findings cannot yet determine whether grip strength testing would replace clinical diagnosis or only serve as a complementary tool, nor do they establish optimal cutoff values for clinical use.
Does grip strength change over time with disease progression or recovery, and could it serve as a longitudinal outcome measure?
Can grip strength measurements help predict prognosis or response to specific treatments?
How do the mechanisms underlying reduced grip strength in ME/CFS (muscle pathology, neurological dysfunction, metabolic impairment) differ from other conditions with chronic fatigue?