This is Episode Ten of “Autoimmune Disease: Pieces of the Picture.” Dr. Deepa Kirk discusses autoimmune thyroid disease, how it is diagnosed, different types of hormone treatments, and questions patients often ask about lifestyle and diet. Dr. Kirk is an Associate Professor of Medicine in the Division of Endocrinology and Metabolism and is also the Medical Director of the UNC Hospitals Diabetes and Endocrinology Clinic.
“The most common question I get is, “What’s going to happen to me and how long will it take to get better?” A related question is, “Why did this happen to me?” I think that’s not an uncommon question for any autoimmune disease. We don’t have great answers.”
– Deepa Kirk, MD
Ron Falk, MD: Hello, and welcome to the Chair’s Corner from the Department of Medicine at the University of North Carolina. This is our series that explores topics related to autoimmune disease, to help patients and their loved ones understand and manage their condition. Today’s episode will focus on autoimmune thyroid disease.
We welcome Dr. Deepa Kirk who is an Associate Professor of Medicine in our Division of Endocrinology and Metabolism and is also the Medical Director of the UNC Hospitals Diabetes and Endocrinology Clinic. Dr. Kirk regularly sees patients at UNC who have thyroid disease, including autoimmune thyroid disease. Welcome, Deepa.
Deepa Kirk, MD: Thank you so much.
Different types of autoimmune thyroid disease
Falk: What on earth is autoimmune thyroid disease?
Kirk: Autoimmune thyroid disease is a complex term. It’s not really one disease. It’s rather a term that refers to a number of different ways that the immune system could affect the thyroid gland.
Falk: Where is the thyroid?
Kirk: The thyroid is on the base of the neck in the midline, so if you were to take your fingers and press right at the bottom of the neck, you probably wouldn’t feel it because most thyroid glands are difficult to feel. It’s about 4 centimeters tall on either side—it’s the shape of a butterfly, we like to say. That’s where it’s located.
Falk: So that organ—what is the thyroid supposed to do in the first place?
Kirk: The thyroid does a lot of things. It produces thyroid hormones. These hormones affect essentially every cell in the body. A simple way to think about what thyroid hormone does, is it is a contributor to metabolism and activity so it may rev up the system, so to speak. If it’s produced in appropriate quantities it keeps many organs and systems in equilibrium.
Falk: So if your thyroid is overworking or hyperactive, how do you feel?
Kirk: If your thyroid is overactive or if you’re producing too much thyroid hormone you may lose weight without meaning to, you may be very hot, you may be sweaty, anxious, or have tremors that you or others may notice. We often hear people say that they have rapid heartbeat or fluttering sensation which we refer to as palpitations.
Falk: And then in contrast, in a hypoactive thyroid, how do people feel with that?
Kirk: With underactive thyroid, as you’d expect, the whole system slows down. People may feel sluggish, tired, constipated. Interestingly, hair and nails can become dry and thin because they’re not turning over and are not being produced in the normal fashion.
Falk: So when the thyroid gets damaged in one way or the other, what can happen? One can have either an active thyroid problem, or a hypoactive thyroid, is that right?
Kirk: That’s correct. Statistically speaking it’s much more common to develop underactive thyroid as a consequence of autoimmunity affecting the thyroid gland, but thyroid diseases are incredibly common, so we definitely see the whole gamut.
Falk: Let’s come back now to this question of what is autoimmune thyroid disease. You’ve said there are many diseases that are encompassed in this word. Help us with that.
Kirk: I would say the most common kind of autoimmune thyroid disease is underactive or hypothyroidism. Some people may have heard the term Hashimoto’s Thyroiditis. It’s really a term that refers to inflammation within the thyroid gland and is named after a physician from Japan, Dr. Hashimoto who described it. Essentially that is the most common kind of autoimmune thyroid disease.
Less common but perhaps more dramatic is something called Graves’ Disease. Again, it’s coined after a Dr. Graves. It causes the thyroid to become overactive. I’d say it’s less common but in a thyroid practice or an endocrine practice, we see a lot of it. The most difficult type of autoimmune disease to diagnose and give a prognosis for is the catch-all term, thyroiditis, which simply means the gland became inflamed in some way. It may not be a permanent condition—most of the time it’s not. It’s a little more difficult to figure out the course of the disease of generalized thyroiditis.
Falk: Just to recap, autoimmune thyroiditis can result in an overactive gland—hyperthyroidism, it can result in a less active gland or hypothyroidism, but it involves inflammation of that organ in one way or the other.
Kirk: Typically it does involve inflammation. In some of the hyperthyroid conditions the antibodies are actually just stimulating the gland and not so much inflaming it. But most of the conditions are associated with inflammation.
The thyroid panel & diagnosis
Falk: How does one actually diagnose any of these problems?
Kirk: There a number of different ways. If a patient has symptoms of overactive or underactive thyroid, you would test a simple lab called a TSH, or thyroid-stimulating hormone.
Falk: Is that part of a thyroid panel?
Kirk: It can be, in fact it’s what we consider the most useful part of the thyroid panel. The TSH is one part of the thyroid panel. Interestingly, the TSH is not a thyroid hormone, per se. It’s another hormone that serves kind of as a barometer or a gauge for how the thyroid’s been doing over the previous 6 weeks.
Falk: Thyroid stimulating hormone, or TSH, comes actually from another endocrine gland.
Kirk: It does. It comes from what we call “The Master Gland,” which is the pituitary gland, a very small gland about a centimeter at the bottom of the brain. It sends signals to the thyroid and TSH is the main signal it sends.
Falk: So the TSH is a useful initial test in the workup of someone who has thyroid disease.
Kirk: It is. It’s the most sensitive test. It changes very quickly and fairly dramatically to even tiny changes in thyroid function.
Falk: Let’s talk more about the thyroid tests in general. There’s the TSH which you’ve already described. What are the other components of a thyroid panel?
Kirk: The two other components of the thyroid panel are some sort of measurement of T4 and another measurement of T3. T4 and T3 are just shorthand terms for the actual thyroid hormones that the thyroid gland makes.
Falk: And TSH stimulates the thyroid gland to produce T4 and T3.
Kirk: That’s correct. Mainly, it stimulates the thyroid gland to make T4, that’s about 80-90% of what our thyroid gland makes, but it also stimulates perhaps 10-20% production of T3, which is just a different form, and perhaps a more active form of thyroid hormone.
Falk: Help me interpret the TSH test which you described as so important, because it’s a little counterintuitive how best to interpret it. If the TSH is elevated, it means what?
Kirk: If the TSH is elevated, it means that the gland is underactive. It is a confusing concept, even to our medical students. I usually tell people that a simple way to think about it is if the gland is dysfunctional in some way, not working properly, the TSH will move in the opposite direction to let you know what’s going on.
Falk: That’s, I suppose, because the pituitary gland is producing more TSH almost to rev up the thyroid in hopes that it makes it work more efficiently?
Kirk: That is absolutely correct. The pituitary gland senses that the thyroid perhaps is under functioning and as a consequence will raise the TSH level in the example of the underactive thyroid.
Falk: So conversely, if the TSH is very low, it would mean that the thyroid gland is overactive, because the pituitary senses too much thyroid production already, right?
Kirk: That’s right. If the thyroid gland is making too much thyroid hormone on its own, there’s really no reason for the pituitary gland to make thyroid-stimulating hormone and appropriately lowers the TSH.
Falk: In addition to the clinical symptoms and this thyroid panel, what other diagnostic tests does one need?
Kirk: If a patient is hypothyroid—underactive thyroid, often times we don’t need any other testing panel. We rely on these simple blood tests, as well as obviously the patient’s history and our exam to decide what’s going on and if treatment’s needed. By contrast, in a hyperthyroid patient whose gland is overactive, there are a lot of different things that can cause a thyroid gland to be overactive and sometimes we’ll use radiology tests. We’ll use something called an iodine uptake scan and that will let us know what part of the thyroid is active and how active it is so we can tailor our treatments.
Treatments for autoimmune thyroid disease
Falk: What are the various treatment options?
Kirk: In an underactive thyroid, it’s a little more simple. We as endocrinologists are fortunate in that if a gland under functions we can usually replace what’s missing, so if a thyroid gland is under functioning we can provide thyroid hormone which is a synthetically made hormone but mimics human thyroid hormone. On the other hand, if a gland is over functioning, there are a number of different options. We can give people medications, or we can give more permanent treatment with radioiodine or even surgery in some cases.
Falk: There are actually a lot of thyroid preparations out there that patients are exposed to. There’s the synthetic version and all sorts of other thyroid preparations. How should a patient talk with their physician about what kind of thyroid replacement medicine they should take?
Kirk: In general, most providers, physicians, and most societies do recommend mimicking normal physiology. Most of us will recommend that a patient take something called levothyroxine, which is named for the hormone your natural thyroid gland makes which is thyroxine. It’s essentially a mimic of what you’re making. We like to mimic what the normal body does to optimize health. There are other preparations out there. There are some preparations made from ground, desiccated (or dried) porcine thyroid, or thyroid from a pig. It might sound a little odd, but it’s been around for many years—many decades, in fact. Some people may feel better on a preparation that comes from a “natural being” even if it’s not a human being.
Falk: Is that preparation as easy to use as the synthetic levothyroxine?
Kirk: It’s not quite as easy to titrate, meaning to adjust the dose, as it’s not as predictable. Everybody may absorb it differently. It has a couple of different thyroid hormones in a fixed concentration. It’s definitely doable—it’s not incredibly complex if you’re used to doing it, but it’s not nearly as simple or predictable as using human synthetic thyroid hormone or levothyroxine.
Timing of medications
Falk: Are there issues with respect to timing when one should take medications—morning, evening, does it make any difference at all?
Kirk: It does make a difference for patients who take medication for hypothyroid, or underactive thyroid. If you’re taking levothyroxine or Armour, which is a porcine thyroid preparation, we do recommend it’s taken on an empty stomach, often in the morning before breakfast. It’s absorbed best if you wait about a half an hour to an hour before you eat breakfast. The most important thing is separating it at least 3 or 4 hours from certain vitamins like calcium, magnesium, iron. We’re talking about supplements here, not necessarily what’s in your diet, simply because you will not absorb your full thyroid hormone dose in that case.
Falk: That’s an important thing to note, because one could imagine taking a handful of pills in the morning including thyroid medication with one’s vitamins at the same time which could include everything you just described.
Kirk: Yes, I’ve often found a mild disturbance in thyroid hormone being lower than usual in a patient who’s been on the exact same dose for a long time. In closer questioning, perhaps the person’s been prescribed iron a few weeks before. Just by separating the two their numbers will go back to normal and there’s no need to adjust thyroid dose in that case.
Lifestyle changes & questions about diet
Falk: In addition to medication for hypothyroidism or an inactive gland or the therapies you’ve just described for a hyperactive gland, are there other lifestyle changes—diet, for example–that patients may be thinking about?
Kirk: That’s a great question and one that I get with increasing frequency. I suspect there’s a lot more information out there regarding this. Patients understandably want to do whatever they can to optimize their health. I would say for autoimmune thyroid disease, that’s a little of a frustration point for both patients and providers because we don’t have a lot of good data as to lifestyle changes and dietary changes that patients can make that will affect and improve the thyroid condition.
We get a lot of questions about iodine. Many people know that iodine is necessary to make sufficient thyroid hormone, but in fact, extra amounts of iodine or very high amounts found in supplements can be detrimental to people with autoimmune thyroid diseases. It can actually make the situation worse in some cases. So in that particular instance, we advise that patients eat normal dietary iodine and eat how you normally do and take your vitamins, but no need to supplement extra.
Falk: Some patients are interested in the effect of certain kinds of vegetables—cruciferous vegetables which are broccoli, cauliflower and things like that. What’s the impact of those kinds of vegetables on thyroid?
Kirk: This question about cruciferous vegetables has been circulating for a bit. Initially the interest, I believe, was raised by animal studies that suggested certain products, compounds in these cruciferous vegetables might be detrimental to thyroid function, basically shutting down the thyroid machinery and making the different components of thyroid production ineffective.
It doesn’t really translate into humans, particularly in normal amounts of food that we eat, even those of us who really enjoy our vegetables. Even those with thyroid disease should feel absolutely free to eat as much as you want. It’s possible that in extremely high doses—we’re talking multiple broccoli-kale shakes a day in a patient who has very mild, early autoimmune thyroid disease—conceivably could have slightly lower thyroid function in that setting, but in the normal every day setting, I absolutely encourage people to eat vegetables that they enjoy.
Falk: Carbohydrates and sugar—does that have an effect?
Kirk: Not that we know of. Again, there is a lot of information circulating, but in terms of data that we can use to help counsel our patients for thyroid disease, there really is not.
Falk: Not good for the development of diabetes, carbs and sugar…
Kirk: Absolutely not. High amounts of carbohydrates and sugar we discourage for many other disease processes.
Falk: What other kinds of lifestyle changes or modifications should patients consider? Are there things that improve quality of life? I could imagine that someone who’s hypothyroid who doesn’t feel like they have enough energy—boy—lifestyle changes that one could imagine beneficial could be potentially really hard to do.
Kirk: It is, and there’s not a one size fits all recommendation. There’s not really one lifestyle change to recommend to affect the autoimmunity part, but as folks are being treated to raise or lower their thyroid levels, the most common concerns we hear are feeling fatigued, and having a lot of difficulty with weight. People may have difficulty losing weight, even when we’re addressing or fixing the thyroid problem. Usually we recommend dietary changes that are recommended for the general population, but not getting frustrated, sticking with it, and knowing that it may take three to six months after the thyroid levels normalize to feel normal again.
Falk: That’s the hard part because patients say, ”I don’t feel well, I feel like my thyroid symptoms are still there,” but you say to them, “All your labs look perfectly normal.”
Kirk: That is a very common scenario, at least in my practice. I’d say about 5-10 percent of folks in whom we as physicians have done a good job at least fixing the numbers, and then we look at our patient and realize we haven’t helped their symptoms as much as we had hoped. It’s unclear why that is. There is some emerging research suggesting that some patients respond to medications differently, mainly combinations of medications. Equally important is to listen to your patient, and there may be other things going on that you haven’t addressed. There are a lot of diseases that coexist with autoimmune thyroid disease that an endocrinologist like myself might address, and a lot of diseases that I rely heavily on my patients and their primary care providers to address.
Patients who have symptoms but normal TSH
Falk: Let’s come back to this TSH test. Let’s say the patient is floridly symptomatic, comes right out of the textbook of hyper- or hypothyroidism, and the TSH is spot-on normal. Then what?
Kirk: In those cases, particularly if you are convinced that the patient has symptoms and signs consistent with underactive or overactive thyroid, we’ll probably not stop at the TSH. You would go ahead and collect the actual thyroid hormones themselves which may be T4 or T3. We’ve been talking about autoimmune thyroid disease affecting the thyroid gland itself—and that is absolutely true, that is what autoimmune thyroid disease affects—but the thyroid can also be affected by non-autoimmune disease. So if that pituitary gland, the master gland, has stopped functioning for some reason—now remember this is more rare—but if that happens, then the signals won’t be sent to the thyroid. The TSH may actually look fine–a little low, a little high, normal–but you can’t trust the TSH in that situation.
So if we think the thyroid is dysfunctional for some other reason besides autoimmunity or a direct attack, we may go on and measure the T3 and T4. Now the difficulty lies—if the patient is having symptoms, and everything is normal, the TSH is fine, T4 and T3 are fine–some practitioners are drawing another test called antibody tests—TPO antibodies.
Falk: Anti-thyroid peroxidase antibodies.
Kirk: Correct. Anti-thyroid peroxidase antibodies are the ones that are associated with autoimmune thyroid disease, which we’ve called Hashimoto’s Thyroiditis. The trouble is, a lot of people in the population, particularly women and particularly as we age, can have TPO antibodies in circulation but not yet have any destruction of the thyroid gland. When these folks come to us with symptoms, it’s a very difficult conversation, because we can’t give thyroid hormone. It’s not safe to give it when the thyroid is still functioning, but people may complain of things like fatigue and difficulty concentrating. Currently, we don’t routinely offer medical treatments for people who just have thyroid antibodies detected.
Common questions patients ask & related research
Falk: What’s the most common question you get from patients with thyroid disease?
Kirk: The most common question I get relates to prognosis, meaning, “What’s going to happen to me and how long will it take to get better?” A related question is, “Why did this happen to me?” I think that’s not an uncommon question for any autoimmune disease. We don’t have great answers. Those two questions together probably comprise most of what people ask me the first time I see them.
Falk: The common three questions I think for all people who take care of autoimmunity are,
“What caused my disease? How did I get it? What’s going to make it go away or make it worse?” Then the other question for many of us here is, “What’s going to make it never come back?” Patients on thyroid replacement medicine may end up being on that medication forever, is that right?
Kirk: That’s true. People who have autoimmune hypothyroidism, or underactive thyroid, I would say the vast majority of people will need to be on some sort of thyroid replacement indefinitely. There are a small number of people who may have had a transient condition and we certainly don’t need to continue medication in them–but for others it does become part of their daily routine.
Falk: In contrast, people who have hyperthyroidism or hyperactive disease, many times you can get that disease under control and no other long-term therapy is required.
Kirk: Correct. We tend to use the same terms that perhaps other specialties use: we say a patient can go into remission. When I first see a patient, sometimes I can give him or her a good idea of their chance of remission. Younger people, people with less severe disease, and women tend to go into remission more often from overactive thyroid, particularly when the high thyroid levels are from Graves’ disease or isolated “thyroiditis,” but certainly we’ve seen it in all age groups and genders.
Falk: What fun new research is exploring the answers to the questions that patients are raising?
Kirk: I think probably the things that patients would really like to hear about—and we don’t have the answers yet—are what treatments could actually modify the disease course? Right now, for underactive thyroid we tell them that we let the immune system do what it’s going to do and we’ll replace your thyroid when it’s all over. As you can imagine that’s a suboptimal answer for a lot of folks.
There are some ongoing research trials as to treatments that might modify the course to avoid the thyroid being destroyed. The problem of course is that a lot of those treatments can be worse than the disease itself—a lot of the treatments we use to affect autoimmune diseases can be toxic in and of themselves. Hopefully, particularly for conditions like Graves’ disease, we’ll be making progress. The other thing that I think patients are interested in is the optimal replacement regimen for those people who don’t feel well on the standard therapy with levothyroxine (or Synthroid which is one brand of thyroid hormone), and there are some outcome trials hopefully coming down the pipeline to help us figure out which patients might do better from the get-go with a different type of regimen.
Falk: Patients are looking for trustworthy sources of information about multiple autoimmune diseases and especially autoimmune thyroid diseases. Where do you tell them to turn?
Kirk: One of my favorite resources is the American Thyroid Association. People are often surprised and happy to learn that there is an American Thyroid Association. It’s an incredibly active group, and there’s an active group of patients who run part of the organization and work in close collaboration with physicians and scientists. I think it’s a wonderful resource. The Endocrine Society also has a resource at hormone.org that is patient-centered. There are navigation tools that give you a virtual tour through the endocrine system, including various thyroid conditions. I think they’re both pretty useful and very reliable resources.
Falk: Thank you, Dr. Kirk. And thanks to our listeners for tuning in. If you enjoy this series, you can subscribe to the Chair’s Corner on iTunes – please leave a comment and give the podcast a rating. You can also like the UNC Department of Medicine on FaceBook to receive updates. Thanks so much.