Lloyd, A R, Wakefield, D, Boughton, C R et al. · The Medical journal of Australia · 1989 · DOI
This study compared the immune systems of 100 ME/CFS patients with 100 healthy people to see if immune problems might explain why ME/CFS causes such severe fatigue. Researchers found that ME/CFS patients had fewer immune cells and weaker immune responses than healthy people. These findings suggest that problems with how the immune system works may be involved in causing ME/CFS.
This landmark study provides objective evidence that ME/CFS involves measurable immune system dysfunction, moving beyond symptom description to biological markers. Understanding these immunological abnormalities may help explain disease mechanisms and guide development of immune-targeted therapies. For patients, documenting immune dysfunction helps validate that ME/CFS has a biological basis rather than being purely psychological.
This study does not prove that immune dysfunction causes ME/CFS—only that it is associated with the disease. The cross-sectional design prevents determination of whether immune abnormalities precede symptom onset or develop as a consequence of chronic illness. The study also does not identify which immune disturbances (if any) are most clinically significant or whether correcting them would improve symptoms.
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →
Spotted an error in this entry? Report it →