NEWS FROM SWEDEN SWEDISH THYROID GUIDELINES AND TSH
Marie in Sweden has sent me the following translation of a Newsletter that has been sent out to every active GP in Sweden in October 2009. It discusses new Swedish Guidelines on when to treat a patient with symptoms of hypothyroidism. Sweden is bringing down the TSH reference range to 0.5-2.5 but the UK still uses the reference range 0.5 to 10.00. Sweden is known to have a pretty well functioning health system, by far better than the NHS. They have the longest life expectancy and the lowest infant mortality rates in the world.
So, if you are being denied a diagnosis because your TSH is within the UK reference range, how about popping over to Sweden, America, Belgium, Germany or Australia to get a diagnosis
Primrvrdens Nyheter is an independent journal aimed at the Swedish primary care sector and in particular clinically active general practitioners. The journal has been the leading news forum for the Swedish primary care sector for over 15 years. Each issue is dedicated to a special thematic topic.
Primrvrdens Nyheter (Primary Care News) 9-10-2009
Doctors need to get better at recognizing and treating subclinical hypothyroidism. It is especially important to treat if the woman is pregnant, or is trying to conceive. This according to Ove Trring, Associate Professor and senior consultant specialized in endocrinology and internal medicine.
Monica Trnell, 55, from Sderhamn, experienced typical symptoms of a low thyroid function for seventeen years. She had gained a lot of weight in a short period of time, suffered from fluid retention, physical pains, and severe memory- and concentration difficulties and was extremely tired. Nothing was found to be abnormal despite of several visits with different doctors, and she was often told that her symptoms had to do with aging. 1997, at age 43, she was given the diagnosis Chronic Fatigue. In 2001 one doctor noticed that her TSH was slightly elevated and prescribed Thyroxine.
It was as if someone switched on the lights. I had not been present for so many years and with medication I was finally given my brain back and could begin to think again. My energy improved and even my other symptoms got better, but it has taken time, says Monica Trnell.
It is not uncommon that patients with hypothyroidism have had symptoms and seen doctors inquiring about treatment for a long period of time before their TSH reaches the limit for what is regarded as abnormal and treatment has been put in place. In the United States the TSH limit for what is considered to be low thyroid function was lowered in 2006 from 4.0 mlU/L to 3.0 mlU/L. The Karolinska hospital in Solna [Stockholm] lowered the same limit from 4.5 mlU/L to 3.5 mlU/L in 2007. If individuals with evident TPOab are excluded from the population sample when the reference range is set, the range becomes even narrower; 0.3-3.5 mlU/L instead of 0.3-4.2 mlU/L. 10 to 20 percent of the Swedish population has evident TPOab, which increases the risk of developing hypothyroidism significantly.
A TSH of above 1.0 can give symptoms
A 20 year longitudinal thyroid study of the population found that those with a TSH of 2.0 mlU/L and above run an increased risk of developing hypothyroidism. And this is independent of whether individuals have evident TPOab or not. The American National Academy of Clinical Biochemistry, NACB, announced in 2003 the guideline that patients with a TSH over 2.5 mlU/L, on two occasions at least 3 weeks apart, may be in an early phase of hypothyroidism.
-And when 95% of the healthy population fall within the reference range 0.5-2.5 mlU/L, this will most likely become the new guideline for when treatment should be considered, which in my opinion is completely correct, said Ove Trring, active at the Karolinska Institute and Sder Hospital in Stockholm.
The reference range for TSH is an average based on a population sample.
-This can imply, for those individuals who normally have a low TSH-T4-relation set point that a TSH value that is increased for them still is a TSH value that falls within the normal reference range. A Danish study shows that a healthy individual’s TSH keeps relatively constant and that an increase of 1.0 mlU/L can be associates with symptoms for the sufferer, said Ove Trring.
Subclinical that is non-subclinical
Subclinical hypothyroidism is a condition with a normal T4 and T3 together with an elevated concentration of TSH, but where the patient does not have any symptoms. This definition is unfortunate since many studies have shown that individuals with subclinical hypothyroidism can indeed have symptoms, e.g. “non-subclinical.” The definition “mild hypothyroidism” is therefore more frequently used.
-Symptoms are often general. The patient might seek care for depressive symptoms, fatigue and other symptoms that can appear as normal ageing, and it is easy to miss that it is rather an early state of hypothyroidism. Since depressive symptoms are common in hypothyroidism even in its early phase, one should consider taking thyroid tests initially before an SSRI is prescribed, according to Ove Trring.
Increasing TPOab can then be an indicator, but it’s not a requirement. An American study published in the journal Thyroid in 2000, where 552 patients via ultrasound or cytology were diagnosed with autoimmune activity in the thyroid, 21 percent lacked evident TPOab. Important as well is the family history. If the patient has thyroid disease or another autoimmune disease in the family, the indication for treatment increases.
A one year trial on Thyroxine If you as a doctor are unsure of whether you have a subclinical patient in front of you or not, it is better that the patient gets a trial with Thyroxine rather than to be without treatment, according to Ove Trring.
-The only thing that can happen from a careful increase of Thyroxine is that the patient does not notice any improvement. Often one year should pass before you can be really sure that the medication has had no effect, and the patient’s TSH should have been around 1 mlU/L for several months.
TPOab-positive youth who have experienced tiredness, unengaged and found it difficult to keep up with school work, as well as women with infertility or recurrent miscarriages, are two groups who Ove Trring has successfully treated with Thyroxine, despite that these individuals have had a TSH within the reference range; from 1.8 mlU/L and above. With Thyroxine treatment the youth felt better and were more successful in school and most women conceived and carried full term.
-I believe that individuals who have been classified as “burned out” also may suffer from undiagnosed subclinical hypothyroidism. When the metabolism drops stress levels increase and the patient’s cognitive abilities to handle problems and crises at home and at work are reduced. And the higher the stress level, the more the immune system is compromised, which can increase the already present inflammatory process in the thyroid.
-I have had many patients who have experienced “burn out” years before hypothyroidism was concluded, says Ove Trring.
Large difference with small dose differentials
-When fine tuning it is sometimes necessary to adjust the dose with 25 micrograms more or less two to three times per week, in order to find the correct dose for the patient’s wellbeing.
The advantages of treating subclinical hypothyroidism is, according to Ove Trring, healthier patients with better quality of life, fewer visits by patients with cases that the health system doesn’t manage to solve, “infertile” women can often become fertile, education and work tasks become easier to handle with a brain that doesn’t run at a low gear and people don’t have to experience a “burn out”. During the last decade several studies have been published showing a correlation between subclinical hypothyroidism and risk factors for heart- and vascular disease; this through various mechanisms associated with the development of arteriosclerosis.
TSH-control important during pregnancy
For pregnant women it is even more important not to have reduced metabolism. And this is true especially during the first trimester since several structures of the fetus’ central nervous system are created then, which requires a sufficient concentration of thyroid hormones for normal development.
-Pregnant women must not have a TSH value exceeding 2.5 mlU/L, in which case they shall be treated with Thyroxine. Pregnant women who are already medicated for hypothyroidism must make sure that they are below 2.5 mlU/L during the entire pregnancy. The vast majority need to increase the Thyroxine dose somewhat even at an early stage of the pregnancy.
By Emese Gerentser