- Last Updated: 06 January 2016 06 January 2016
Are FM and ME/CFS the same illness?
Research authorities vary in viewpoint as to the relation of FM and ME/CFS, but the best research to date indicates that the two illnesses, while often associated, are different and separable—both in nature of causation and in their pathophysiologies (effects on processes in the body.)
Medically, FM is classified as a rheumatological illness, and FM is most commonly diagnosed and treated by rheumatologists. ME/CFS historically comes more under the rubric of internal medicine or infectious disease. This difference occurs because ME/CFS very often presents with viral-like or infectious symptoms, which do not occur as often in FM. The primary symptom complexes in FM are 1) pain; 2) sleep disturbance; 3) fatigue and exhaustion. Viral and other infectious-type symptoms aremuch less frequent.
However, because of the similarities of many of the ME/CFS and FM symptoms, including the fact that many patients can have both, differential diagnosis can be a problem. It is very important that the two illnesses be diagnosed correctly because treatments for each are somewhat different.
A person with ME/CFS who is diagnosed with FM and treated accordingly may run into severe problems; and a person with FM who is incorrectly diagnosed with ME/CFS may also be treated improperly and lose the benefits of helpful treatments.
The fact that the two illnesses are the province of separate specialties can also lead to diagnostic problems. As a rheumatologist is trained in rheumatological illnesses, there are occurrences of ME/CFS being diagnosed as FM when the physician is not well-versed in ME/CFS diagnosis. And an infectious disease specialist may be prone to misdiagnosing FM as ME/CFS.
Therefore, when there is doubt about which illness a patient has, she or he should become familiar with the differences between the two illnesses and seek a physician who knows how to diagnose both illnesses.