The Mysteries of Chronic Fatigue Syndrome
Research to date has failed to provide convincing evidence that a single infectious agent causes the illness. "It is likely that more than one infectious agent is involved in producing CFS," says Johnson.
Laboratory researchers are investigating cellular activity to better understand how viral infection affects cell functions and the immune function. As with all studies of CFS, findings have not proven consistent, says Johnson. "To date, there are still no useful viral or immune diagnostic markers for CFS, although there is promising work being done."
With the diverse symptoms shown by chronic fatigue sufferers, it is hardly surprising that there is no firmly established treatment, says Johnson. While many physicians recommend low-dosage antidepressant therapy, at least one study showed that it had no effect. A few drug treatments have been identified as important sources of symptom relief and symptom management. But the vast majority of antiviral medications, immune modifiers, antifungal agents, vitamins, and minerals that chronic fatigue patients try have not been tested.
While exercise and psychological counseling have been suggested to increase activity levels and interrupt cycles of depression, studies indicate that they are promising but high dropout rates show that they do not fit all cases of chronic fatigue.
Researchers still don't understand why many who suffer from chronic fatigue never are cured. But studies consistently show that those who are less likely to have complete recovery tend to be older and suffer from depression or anxiety disorder. "There's been some pretty good physiological research, but it's been frustrating, too," says Johnson. "Findings look promising but tend not to be replicated [in subsequent studies]. There's something there, but we're having lot of trouble grasping it, pinning it down."
CFS is a multidimensional illness and challenges traditional perspectives on illness, Johnson tells WebMD. "There's been progress, but it's been incremental. There are still many unanswered questions."