Tuesday, September 4, 2012

When your blood is drawn could affect TSH level and hypothyroidism diagnosis

tsh-hypothyroidism-hashimotos-afternoon

If you check your thyroid levels in the afternoon with a blood draw, results may come back normal even though you’re hypothyroid, according to a new study. Checking your TSH in the morning can give you more accurate results.

Like other hormones in the body, thyroid-stimulating hormone (TSH) follows a daily rhythm and is not consistent throughout the day. Researchers in the study evaluated untreated patients with subclinical hypothyroidism along with patients taking a T4 hormone. They tested the participants’ TSH before 8 a.m. and again between 2 and 4 p.m.

In both groups TSH dropped substantially during the afternoon test, which would have led to hypothyroidism not being diagnosed in about 50 percent of the untreated participants.

Their TSH was 5.83 mU/L in the morning and 3.79 mIU/L in the afternoon. In the group being treated with thyroid medication TSH was 3.27 mIU/L in the morning and 2.18 mIU/L in the afternoon.

A 2004 study also showed that late morning, non-fasting TSH dropped 26 percent compared to early morning, fasting TSH.

Timing of TSH test adds new ammunition to thyroid range controversy

The researchers concluded that the timing of your blood draw plays an important role in how to decipher the results of your thyroid panel.

Unfortunately, even with an early morning blood draw, many hypothyroid patients still slip through the cracks because most doctors use ranges that are too wide.

It’s still very common for doctors to diagnose hypothyroidism using a TSH range of 0.5 to 5.0 mIU/L even though the American Association of Clinical Endocrinologists recommended years ago the range should be 0.3 to 3.0 mIU/L.

Functional medicine uses narrower ranges and more markers to identify hypothyroidism

In functional medicine we use an even narrower range of 1.8 to 3 mIU/L. We also know in functional medicine that looking at TSH alone can miss hypothyroidism.

For some, TSH may be normal but other thyroid markers are off. That’s why it’s important to order a thyroid panel that looks at a more complete thyroid picture, which can include total and free T4 and T3, reverse T3, free thyroxine index (FTI), T3 uptake, and thyroid binding globulins. Many conditions can cause poor thyroid function, including inflammation, hormonal imbalances, and chronic stress. Evaluating other thyroid markers gives insight into these imbalances.

Always screen for autoimmune Hashimoto’s hypothyroidism

In addition to these markers, anyone with hypothyroid symptoms should be screened for Hashimoto’s, an autoimmune disease that attacks and destroys the thyroid gland. Hashimoto’s accounts for about 90 percent of hypothyroid cases in the United States. You screen for Hashimoto’s by checking TPO and TGB antibodies.

Although thyroid medications may be necessary to maintain thyroid function, they do not address the immune system’s relentless attack against the thyroid gland. Not managing Hashimoto’s increases the risk of developing other autoimmune diseases. These can include pernicious anemia, rheumatoid arthritis, vitiligo, and Type I diabetes.

Ask my office how to properly evaluate your thyroid symptoms and lab markers for appropriate thyroid management.

 

3 comments:

  1. How does your office properly evaluate your thyroid symptoms and lab markers for appropriate thyroid management??

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  2. Would it be best if your appt is in the afternoon to not take your med until after your lab draw..since labs are so variable at any time of day much like ones blood sugar or blood pressure..? There are no functional docs in IA. .I'm a research nurse with lots of questions and few to give or offer answers in how to precisely handle this question. I am also having what I believe to be SIBO symptoms. . Find my family doctor and he just prescribed famotidine and pantoprazol which I feel only bandaid my symptoms until the end of the therapy and can cause future harm to bones and kidneys and I do not wish to take both medications all the time. I don't want a band-aid I want to know why and I guess that's the research nurse in me I want to fix the problem not cover it up. I have seen a Rheumatologist for possible ra I don't believe I have it and he does not either but I had a very high CCP blood test while my other inflammatory markers were within normal limits. Do you believe an elevated CCP of 80 could be from intestinal issues caused by SIBO? I have much bloating within half an hour of eating muscle pain around my ribs varying stools, and approximately a year ago I was tested for Heliobacter via a blood test and not the actual breath test and that was negative according to my doctor but I question if I have enough acid in my stomach to digest my food versus having too much.. I am on align probiotic for 2 weeks now and still continue to have symptoms. I also have hypothyroidism and fibromyalgia and from a serious drug interaction from the statins combined with erythromycin, niacin and an increase in my statin dosage I ended up having rhabdomyolysis and weeks later pancreatitis which obviously from the pancreatitis has left my digestion quite messed up since the time of this unfortunate happening with the medications. I know where I have low motility although no one seems to Medicate that nor tell me what to do for that so it's just mt own guess work and research on my part. Your ideas? I'm interested in looking into the Malaysian process because of the research I've done so far as I believe a lot of my symptoms relate to that but also could be marred by the fact of the statin drug interaction and how it messed up my body and tripled my liver enzymes ..ideas welcome PLEASE & Thanks for considering/addressing my questions in advance!

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  3. I also forgot to mention that in the 90's I was dx'd with a case of shigella while in hospital for ruptured hemorraghic ovarian cyst. Was tx with Bactrim for the shigella I believe. .and f/u visit c/s was normal. What lasting damage could that have caused in your own opinion?

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