In the last lecture I talked about tests you can do at home before seeing your doctor. Or you can use them to monitor how well your treatment is working. Today I’ll talk about Subsclinical Hypothyroidism or SCH.
The prefix “sub” means below or under. Like suboptimal or submarine. Subclinical in this case means less than clinical. In other words, a clinical case of hypothyroidism is obvious, because there are the symptoms, and the blood tests indicate that the problem exists. There is high level of TSH and low level of T4 and T3.
We talked about all these hormones before but let me refresh your memory. TSH stands for Thyroid Stimulating Hormone. It’s produced in the brain by the pituitary gland and its job is to stimulate the thyroid cells, make them work harder to produce more thyroid hormones. When the thyroid hormone production goes down, the level of TSH goes up, to stimulate the thyroid gland. In other words, higher TSH means that the body is not happy with thyroid hormones production and wants more of them. On the other hand, if thyroid hormones are too high, the level of TSH is going to be very low, so as not to stimulate the thyroid gland.
In most labs “normal” TSH level is from 0.4 to 4.0 or 4.5. Higher level of TSH means that the person has hypothyroidism. The optimal level of TSH is not 4 or 4.5. It is less than 2. That’s what 95% of normal people have. There is a discussion about reducing “normal” TSH to reflect that. But for now, if your level is higher than 2 or 2.5, there is a very good chance that you have hypothyroidism. The chance is almost 100% if your TSH is higher than 4-4.5.
Suboptimal hypothyroidism (SCH) is defined as a situation when TSH is high but T4 is normal and there are no or minimal symptoms. Let’s discuss these 3 elements (TSH, thyroid hormones and the symptoms) in details.
First TSH. High TSH, by definition, is the sign of low thyroid. The brain tells the pituitary gland to make more and more TSH because it senses the lack of thyroid hormones in the blood. The cells of the body send signals to the brain that they are not getting enough thyroid hormones, and the brain tells the pituitary to make more TSH. That’s why, in my opinion, high TSH, regardless of anything else, is enough to make a diagnosis of hypothyroidism.
The second part of the definition is that while TSH is high, T3 and/or T4 instead of being low, are “within normal range.” We have already discussed the idea that if you are in the “normal range” it does not mean that you are normal. For example, normal range for T4 is 5 to 12. If you were always 10 (in the range) and now you are 7 (also in the rage) we will call you normal, even though you are much lower than you used to be. This is why the brain is making more TSH. You can download a free special report about how a person can have low thyroid and have “normal” blood tests.
The third part is the symptoms. According to the definition, a person with SCH has no or minimal symptoms. As you know, hypothyroidism develops slowly, over a course of months or even years. The symptoms appear very slowly, so the patient has time to get used to them and it becomes “new normal” for her. That’s why she may think that she has no symptoms or that she has mild symptoms, because she had a long time to accommodate to them.
SCH is fairly common, especially as people get older. The incidence is 5-10% in general, but it’s more like 20% in women over 60.
It is usually diagnosed during a routine blood test, like a yearly physical or in early pregnancy.
The symptoms of SCH are the same as those of regular hypothyroidism, such as low energy, feeling colder than others, gaining weight, depression and brain fog, and all the others. You can download the list of all the symptoms here.
The causes are the same as in regular hypothyroidism, except the patients diagnosed with SCH tend not to be iodine deficient. The main cause is the Hashimoto’s disease, slow destruction of the thyroid gland by your own immune system.
The treatment is the subject of some debate. To treat or not to treat, that is the question. Many doctors feel that no treatment is necessary, since T3 and T4 are “normal” and the patient has minimal symptoms. They recommend “watchful waiting” which means doing nothing, and checking T3, T4 and TSH every 6 months. They are willing to wait till TSH reaches 10, some even wait till 15, but most doctors agree that 10 is the red line. They are willing to wait till TSH reaches 10 and then they will begin treatment with Synthroid, even though everything else is still the same – minimal symptoms and T3 and T4 withing normal range.
Then there is the minority of doctors, myself included, who feel that if one’s TSH is above 2-2.5 and certainly if it is above 4, this is a clear sign of low thyroid and needs to be treated. Because if you dig deeper, ask about symptoms, look for other signs of hypothyroidism and look at previous blood tests it often becomes clear that a change has taken place. A change from normal thyroid to low thyroid. So not treating the patient until TSH goes up to 10 or 15 is crazy, tantamount to malpractice.
Of course, you don’t start the treatment after just one blood test. Many times, test results come from a lab as abnormal, something that you did not expect. In a case like that the first thing I do is repeat the test, and very often it comes back normal. Problem solved.
But if TSH is 4.9 the first time, you repeat it and it’s now 4.8 or 5.0, then it’s probably true. You can repeat it again in a month and if now it is 5.1 then it must be correct. Your TSH is too high.
As I said, there is a difference of opinions when to start treatment. To me SCH is hypothyroidism and needs to be treated. If you TSH is high, this is your body’s cry for help. This is especially true during pregnancy. According to some studies up to 30% of pregnant women develop this type of hypothyroidism and I think they should be treated. In general, pregnant women should be carefully monitored for hypothyroidism because it develops quite often during pregnancy. And in pregnant women it’s better to err on the side of treatment, because developing fetuses need enough thyroid hormone.
Generally, women with low thyroid have difficulty getting pregnant. Even if they do conceive, there is increased risk of abortion and various complications like hypertension and others. When it comes to the developing baby, it absolutely depends on adequate mother’s thyroid function. Thyroid hormones are not only important for the overall physical development and growth of the baby, it’s especially important for the brain and nervous system. Children born to mothers with low thyroid often have lower IQ and decreased psychomotor development.
To summarize, Subclinical Hypothyroidism is hypothyroidism and needs to be treated.
If you know someone who might be interested in low thyroid, please refer them to LowThyroidDoctor.com so they can download this ebook. Also, if you have questions or comments, please email to DrTeplisky@gmail.com.
As an additional bonus, while available, you can get a free, no obligation 30 min phone consultation with me to see if I can help you figure out if you have low thyroid and what I can do to help you. Just book it online or call my office at 718-769-0997.