If you Google, (or any other search, for that matter) "symptoms of hypothyroidism", amongst the most common are fatigue (tiredness), weight gain, and hair loss (alopecia). It would be reasonable to check a TSH in this setting.
Other symptoms such as changes in skin texture (usually increase in dryness), constipation, bad menstrual cramping (dysmenorrhea), muscle aching (myopathy)
As the most common cause of hypothyroidism is autoimmune, other autoimmune gland problems such as Addison's disease (autoimmune adrenal insufficiency), Type 1 Diabetes Mellitus (autoimmune destruction of pancreatic islet cells), and vitiligo (autoimmune destruction of the pigment-producing cells in the skin) should also trigger routine laboratory evaluation for TSH.
Medical conditions, such as congestive heart failure, dementia (confusion) anemia (low blood count) without specific cause, high cholesterol (hyperlipidemia), or an abnormal heart rhythm (cardiac dysrhythmia, prolonged QT interval on EKG) can also be associated with hypothyroidism.
Other reasons to check? I think of family history in a first degree relative (parent, sibling, child), as well as pregnancy. In a child, triggers to check also include poor growth, or, actually, remarkable improvement in school performance, as hypothyroiid kids sit still and pay attention, go figure!
Sunday, April 14, 2013
Saturday, April 13, 2013
Should my hypothyroidism be treated?
Continuing through the ATA/AACE Guidelines for Hypothyroidism in Adults (Endocrine Practice 2012;18(No.6), let's talk about whether or not hypothyroidism should be treated. While the answer may appear obvious, there are some nuances.
First, how to define hypothyroidism.
NHANES III (a great-big population study of Americans) found those who were not on thyroid medication and said, "I have a healthy thyroid" can have a TSH of up to 4.5uIU/mL. When those same patients were more closely sorted out, and removed those with positive anti-thyroid antibodies, pregnant, or on medications such as estrogens (like birth-control pills), androgens (like testosterone), and lithium, the upper limit of normal dropped to 4.12uIU/mL.
Another group altogether, the National Academy of Clinical Biochemists, found 95% of patients without evidence of thyroid disease have a TSH less than 2.5uIU/mL. However, the upper limits of normal in the NHANES group (above) was likely defined by the top 97.5%, so this is a little bit like comparing apples to oranges. . . . .
TSH can vary amongst ages and races, with a TSH as high as 7.8uIU/mL being acceptable for Mexican-Americans >80years old. It can even vary, within the normal range, in the same person by 50%. This means someone can have a TSH of 2.5uIu/mL one day, 1.25uIU/mL another day, and 3.75uIU/mL yet another day.
So, now on to the treatment (let's answer the question, yes):
If your TSH is higher than 10uIU/mL, you won't find many folks who will argue with you that medication is the right way to go. If it is 0.5-2.5uIU/mL, your thyroid is most likely functioning properly, and medication would not necessarily address symptoms.
How about the grey area? Let's split it in half. Some studies have shown those with TSH 2.5-4.5uIU/mL who have high cardiovascular risk factors such as elevated lipoprotein a (Lpa), poor endothelial function, and high intima-medial thickness (all research tests, not widely clinically done), may have benefit from treatment, though it remains controversial. The other population, better studied, are pregnant ladies (even antibody-negative), in order to decrease risk of miscarriage and stillbirth.
The other half, those with TSH 4.5-10uIU/mL, are not statistically likely to benefit. However, by the time patients make it to my office (I am, after all, an endocrinologist), they have had enough drive for treatment that I will oblige as long as the patient is willing to take medication daily and have labs regularly.
First, how to define hypothyroidism.
NHANES III (a great-big population study of Americans) found those who were not on thyroid medication and said, "I have a healthy thyroid" can have a TSH of up to 4.5uIU/mL. When those same patients were more closely sorted out, and removed those with positive anti-thyroid antibodies, pregnant, or on medications such as estrogens (like birth-control pills), androgens (like testosterone), and lithium, the upper limit of normal dropped to 4.12uIU/mL.
Another group altogether, the National Academy of Clinical Biochemists, found 95% of patients without evidence of thyroid disease have a TSH less than 2.5uIU/mL. However, the upper limits of normal in the NHANES group (above) was likely defined by the top 97.5%, so this is a little bit like comparing apples to oranges. . . . .
TSH can vary amongst ages and races, with a TSH as high as 7.8uIU/mL being acceptable for Mexican-Americans >80years old. It can even vary, within the normal range, in the same person by 50%. This means someone can have a TSH of 2.5uIu/mL one day, 1.25uIU/mL another day, and 3.75uIU/mL yet another day.
So, now on to the treatment (let's answer the question, yes):
If your TSH is higher than 10uIU/mL, you won't find many folks who will argue with you that medication is the right way to go. If it is 0.5-2.5uIU/mL, your thyroid is most likely functioning properly, and medication would not necessarily address symptoms.
How about the grey area? Let's split it in half. Some studies have shown those with TSH 2.5-4.5uIU/mL who have high cardiovascular risk factors such as elevated lipoprotein a (Lpa), poor endothelial function, and high intima-medial thickness (all research tests, not widely clinically done), may have benefit from treatment, though it remains controversial. The other population, better studied, are pregnant ladies (even antibody-negative), in order to decrease risk of miscarriage and stillbirth.
The other half, those with TSH 4.5-10uIU/mL, are not statistically likely to benefit. However, by the time patients make it to my office (I am, after all, an endocrinologist), they have had enough drive for treatment that I will oblige as long as the patient is willing to take medication daily and have labs regularly.
Thursday, April 11, 2013
Guidelines to Treat Hypothyroidism
Today, I was reminded by my Medscape News Diabetes and Endocrinology about the American Association of Clinical Endocrinologists (AACE) and the American Thyroid Association (ATA) Guidelines to treat hypothyroidism that came out in the Nov/Dec 2012 issue of Endocrine Practice.
This guideline paper helped to validate what I have been saying. Specifically, that the TSH is the best screening test for hypothyroidism, levothyroxine is the standard treatment, and that treating subclinical hypothyroidism with TSH higher than normal, but less than 10, should be patient-specific.
In the United States, the most common cause of an underactive thyroid is Hashimoto's thyroiditis, which is an auto-immune condition. It affects about 0.3% of the general population, and women 5-10 times more often than men. Sometimes it causes an enlarged gland, but not always. About 75% of the time, antibodies (anti-TSH, anti-TPO) are positive, and once they are, they usually remain that way, so repeating thyroid antibody titers is generally not useful.
Determining who has hypothyroidism is important, but the manner of screening in terms of whether to do it at all (Royal College of Physicians of London doesn't feel it's important in a healthy adult population), to more aggressive screening recommendations of the ATA of both men and women over the age of 35 should be screened every 5 years.
Overall, there were 52 recommendations, and I'll try to cover a few more tomorrow, as it's getting quite late.
This guideline paper helped to validate what I have been saying. Specifically, that the TSH is the best screening test for hypothyroidism, levothyroxine is the standard treatment, and that treating subclinical hypothyroidism with TSH higher than normal, but less than 10, should be patient-specific.
In the United States, the most common cause of an underactive thyroid is Hashimoto's thyroiditis, which is an auto-immune condition. It affects about 0.3% of the general population, and women 5-10 times more often than men. Sometimes it causes an enlarged gland, but not always. About 75% of the time, antibodies (anti-TSH, anti-TPO) are positive, and once they are, they usually remain that way, so repeating thyroid antibody titers is generally not useful.
Determining who has hypothyroidism is important, but the manner of screening in terms of whether to do it at all (Royal College of Physicians of London doesn't feel it's important in a healthy adult population), to more aggressive screening recommendations of the ATA of both men and women over the age of 35 should be screened every 5 years.
Overall, there were 52 recommendations, and I'll try to cover a few more tomorrow, as it's getting quite late.
Wednesday, April 10, 2013
Maiden Voyage
Well, here goes nothing! My name is Julia Warren-Ulanch, MD, and I have trained to be an Adult and Pediatric Endocrinologist. That means that after 4 years of college, I had the fortune to complete 4 years of medical school, 4 years of residency, and 4 years of fellowship. Yes, this means more years after graduation from high school than the years spent before, and by the time I was done, I finished the 28th grade. Although I love what I do, I still wonder what I'll be when I grow up.
Right now, I am in private practice in Raleigh, North Carolina. Carolina Endocrine, PA, to be exact. I've been there since I finished my fellowship in 2006. Day-to-day, I see adults and children with hypothyroidism (under-active thyroid), hyperthyroidism (over-active thyroid), and thyroid nodules (lumps and bumps on the thyroid). Some of my patients struggle with not growing tall enough or fast enough, or with growing too much. Others have started puberty too early, or never started. Problems with reproduction? I see that too, from low interest in trying to irregular cycles or even pituitary problems that can interfere, like prolactinomas. Even blood pressure can sometimes be an endocrine problem, low or high. Of course, I can't address everything, but I do my best to help all types of patients that come in. Even the diabetics, though this isn't my focus.
Later this month, I'll be going to the spring meeting of the American Thyroid Association, about treatments for hypothyroidism. I'll plan to post more after that meeting. Maybe even before then, if I run across something interesting.
Thanks for reading, and have a great day!
Right now, I am in private practice in Raleigh, North Carolina. Carolina Endocrine, PA, to be exact. I've been there since I finished my fellowship in 2006. Day-to-day, I see adults and children with hypothyroidism (under-active thyroid), hyperthyroidism (over-active thyroid), and thyroid nodules (lumps and bumps on the thyroid). Some of my patients struggle with not growing tall enough or fast enough, or with growing too much. Others have started puberty too early, or never started. Problems with reproduction? I see that too, from low interest in trying to irregular cycles or even pituitary problems that can interfere, like prolactinomas. Even blood pressure can sometimes be an endocrine problem, low or high. Of course, I can't address everything, but I do my best to help all types of patients that come in. Even the diabetics, though this isn't my focus.
Later this month, I'll be going to the spring meeting of the American Thyroid Association, about treatments for hypothyroidism. I'll plan to post more after that meeting. Maybe even before then, if I run across something interesting.
Thanks for reading, and have a great day!
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