A link between chronic fatigue syndrome (CFS) and lower levels of key thyroid hormones has been discovered which creates a promising outlook for treatment of the debilitating disease.
New research published in Frontiers Endocrinology indicates that chronic fatigue syndrome can be explained by lower thyroid hormone levels but may be distinct from thyroidal disease.
CFS is a common disease with unknown causes where the individual has lengthy spells of weakness, fatigue and depression. Diagnosis is predominantly based on symptoms and ruling out any underlying medical conditions, instead of lab tests and physical examination.
There is no recognised treatment for the condition; however, this new finding could be the first step to finding treatment for the illness.
Similarities to other conditions
Several symptoms of CFS resemble those of hypothyroidism, which is a condition where the thyroid gland does not produce enough thyroid hormone.
In hypothyroidism, the body attempts to encourage thyroid hormone activity by releasing more thyroid-stimulating hormone. This, however, does not happen in patients with CFS.
It was this contrast in thyroid-stimulating activity which led study authors to hypothesise that chronic fatigue syndrome is caused by low activity of thyroid hormones in the absence of thyroidal disease.
Comparing thyroid function
A research team led by Dr Begoña Ruiz-Núñez compared thyroid function and markers of inflammation between 98 CFS patients and 99 healthy controls.
The CFS patients had lower serum levels of certain key thyroid hormones such as triiodothyronine (T3) and thyroxine (T4), but normal levels of thyroid-stimulating hormone.
However, the CFS patients had relatively higher levels of another thyroid hormone called ‘reverse T3’ or rT3.
This appeared to be due to a shift in hormone production, where the body preferred to convert T4 to rT3 instead of producing T3. The low T3 levels found in CFS patients coupled with this switchover to rT3 could mean that T3 levels are severely reduced in tissue.
Núñez said: “One of the key elements of our study is that our observations persisted in the face of two sensitivity analyses to check the strength of the association between CFS and thyroid parameters and low-grade inflammation.
“This strengthens our test results considerably.”
What is the future of CFS diagnosis?
The researchers believe inclusion of patient information, such as duration of illness, would enable a correlation with their biochemical profiles.
Despite the study finding a link between CFS and low thyroid hormones, a definitive cause of the condition remains unknown.
Source: ME Association
You can reverse the rt3 conversion and convert instead to t3 with n-acetyl cysteine. Some ME is possibly a type of NIST.