It would be pretty hard not to have heard about thyroid-related medical issues or Hashimoto’s disease in today’s information age. Of course, hearing about it doesn’t mean most people are aware of what really is at stake, which is autoimmune disease. This is pretty shocking considering perhaps one in eight people suffer from the most common form of these related thyroid conditions—and these numbers are rising. It is equally troubling because if these diseases are left untreated, the health consequences can be serious, perhaps even deadly. Thankfully, if diagnosed and treated early, these problems are relatively easy to control. Dr. Anupam Kotwal, a hyperthyroidism guidelines committee member at the American Thyroid Association, underscored this recently when he spoke to WellWell about the related dangers, symptoms, solutions and precautions.
What is the thyroid and how is it related to autoimmune diseases?
The thyroid gland is a small gland located at the lower part of the neck in the middle and it produces the thyroid hormone. It uses iodine in the blood to produce thyroid hormone. That’s its main function in terms of autoimmune conditions. It is very commonly involved in autoimmunity. The most common condition is called Hashimoto’s or Autoimmune Thyroiditis. This can lead to underactive thyroid hormone production or so-called hypothyroidism. The other autoimmune condition, which is not as common, is called Graves Hyperthyroidism. That’s an overactive thyroid gland and then sometimes there can be temporary or transient issues and mild autoimmunity or inflammation of the thyroid gland.
Is Hashimoto’s the most common condition?
Yes. The prevalence or how frequently this occurs has been increasing over the years. In North America and the Western world about one in eight to one in 10 individuals will have Hashimoto’s. So, it’s actually quite common. Not all of them will have a low or underactive thyroid; about half or three-quarters of them may develop an underactive thyroid at some point in their life. Graves is rare, about one in 20 people—around that range—will develop it.
What’s causing these different strains? Is each condition different or caused by a separate thing and exactly how dangerous are they?
There is some familial link that causes thyroid autoimmunity, especially Hashimoto’s. People may have other family members who have either thyroid autoimmunity or other autoimmune conditions. There are also environmental aspects. So there has been some link with general viral infections that can affect the thyroid and make someone predisposed to autoimmunity. There has also been some link to iodine excess and deficiency. Excess of iodine can increase the risk of Hashimoto’s or thyroid autoimmunity. And then there is a link to general stress, a poor lifestyle or injury that could increase autoimmunity. We don’t know that for sure. So as of now, it’s predominantly a mix of a family history and some deficiency or excess of iodine.
How dangerous are these conditions, whether it’s Hashimoto’s or Graves or one of the other related conditions?
If they are not diagnosed and treated in a timely manner, then they can be quite dangerous. For example, Hashimoto’s can lead to an underactive thyroid if it’s not managed with hormone replacement. And, if it’s not diagnosed timely, it can lead to fatigue, tiredness, feeling too cold, maybe gaining some more weight and more sleepiness. So, mild things can affect the quality of life. If it continues for more than a few months and is not treated, it can lead to a slowed heart rate, which can affect blood pressure and poor concentration and memory. And if it’s very severe, which is what we call mixed edema where people are almost in a coma state, their brain and heart function are so slowed down that they will need to be admitted to get fluids and thyroid hormone support. Usually, that’s seen if it’s months or years of an untreated underactive thyroid gland. On the other hand, overactive thyroid gland, which can happen with Graves autoimmunity, everything is a little bit fast, a fast heart rate, hot and sweaty and some tremors or shakiness. But again, if it’s severe and not treated initially, it can lead to irregular heart rhythm or things like atrial fibrillation that increases the risk of stroke and increased blood pressure. It can also lead to a severe emergency-like scenario in that case. So, if both under or overactive thyroid are not timely diagnosed and managed, you’ll experience some mild issues that can become fairly severe if untreated.
It sounds like a lot of people may have a thyroid condition and they’re unaware of it. Is that a fair statement?
So that’s the issue with the symptoms. They can be quite nonspecific. Sometimes it’s a deficiency of vitamins, poor sleep or iron deficiency. The symptoms may not be very specific. If there is a mix of symptoms, for example, if someone is feeling colder, more tired, more sleepy, constipated, all of those going on, that would likely point toward an underactive thyroid as opposed to some other issues. This is why we recommend to at least keep your annual appointments with your primary care physician, even if you think you’re the healthiest person. Your healthcare provider will include these questions and concern for tiredness or symptoms like this and then the healthcare provider will do a thyroid function test and evaluation.
What’s the reason for the rise in these conditions?
The answer is not clear. In the 1990s about five to six percent of people in the U.S. had Hashimoto’s. From 2010 to 2012, it rose to 10 percent, and in 2019, about 12 percent of people had Hashimoto’s. Some of it is just better detection, better diagnosis and better healthcare. There’s also more awareness both from the medical community, as well as the general non-medical community about these conditions. There has been some rise in autoimmune conditions in general, for example, rheumatoid arthritis or autoimmune joint or skin issues. There has been a link with lifestyle so we do know that poor diets, a rise in weight gain and obesity and a more sedentary and poorer lifestyle may increase generalized autoimmunity. It’s very tough to give a clear answer because again, there are so many things that can affect it.
Another factor to consider is that estrogen, which is the predominant reproductive hormone in women, has been linked with this. So, it could be that they’re just prone to more autoimmunity. Women are also more likely to have autoimmune rheumatoid arthritis or autoimmune skin issues and things like that. Women are more likely to have thyroid enlargement that is felt, which increases the chance that they’ll get a hormone test or evaluation as compared to men. We know that women do seek health care more commonly than men, and so some of it also is that if they are more involved in their health, they are more likely to be diagnosed earlier.
Women seem more impacted than men by these diseases—I think it’s a rate of three to one. Is that correct and, if so, why?
Yes, absolutely, depending on what condition we talk about. The autoimmune is both over and underactive again about three to five times more in women than men. And again, this discrepancy increases as the age goes up to the 50s or 60s.
Are there other demographic groups that are disproportionately at risk?
We talk about inequities and disparities in thyroid diseases. Autoimmunity affects Caucasians most commonly not only thyroid but other autoimmune conditions as well.
How much of that is an actual connection and how much of that is better healthcare utilization?
We think there is a link there. It was shown that people living far away from major medical centers or rural populations or minorities, even if they are in inner cities, are likely to be diagnosed with it later when it’s more severe. Some of it is linked to just how they are interacting with the healthcare system. So, the data kind of gets affected by those factors. It’s hard to say if there is an actual increased risk in a certain population or if it is just that some have better access to healthcare.
Can children and young adults also suffer from these sorts of diseases?
It is most common in middle age to mature adults. Our longevity is improving so 50s and 60s a few years ago would be called that and now that’s young. It can affect adolescents around the age of 10 or 11, not earlier than that. The highest frequency is in women in their 50s and 60s.
But you know adolescent time or early adulthood is a tough time because that’s the group that may not be as involved in their health because they have so many other things going on that it can go undiagnosed. And if we don’t start thyroid hormone appropriately, they can have all the issues that we discussed earlier, along with growth retardation, delayed or decreased attainment of height and appropriate weight for both underactive and overactive. I was diagnosed with Hashimoto’s or autoimmune hypothyroidism in high school. It involved some initial testing and monitoring and then the doctor finally said that I would need to start thyroid hormone because it’s not the hormone function that was recovering. So definitely can happen.
Can a thyroid condition lead to someone having weight issues?
I get asked this from patients pretty much every day. So underactive thyroid hypothyroidism, if not treated for a few months, can lead to decreased metabolism, which will lead to increased weight and fatigue. People are less likely to be active. It can also lead to some fluid retention which will come with some increase in weight or puffiness. It usually does not lead to severe weight gain. So, if we see that in a patient or an individual, we also want to think of other factors that can be going on. If someone presents with unclear weight loss, we do the thyroid function test to see whether they are under or overactive. but keep in mind that we don’t want to hang our hats just on the thyroid and not miss other issues like sleep disorders and other metabolic issues.
What are the treatments and remedies?
The treatment for underactive thyroid is giving the patient a thyroid hormone pill. The most common formulation is called levothyroxine. It’s taken as a once-a-day pill in the morning, ideally on an empty stomach. And usually that treatment works for most people. There are some cases where absorption may not be well or if someone’s taking medicines for stomach acidity or ulcer, it can decrease the absorption. In those cases, we sometimes give gel capsules, so the capsule doesn’t really require to be broken down by stomach acid and the absorption is better. And again, most people do well with either of these formulations. There is a subset where, for example, especially patients who’ve had their whole thyroid taken out from surgery or have significant hypothyroidism, that we’ve been giving them levothyroxine for a few months and even with normal levels, they feel poorly that includes fatigue, mental fogginess or trouble with concentration. Maybe some weight gain despite normal tests. And that’s when we question whether they are getting adequate treatment just with levothyroxine. That’s the group where we try and add on T3, which is another hormone that the thyroid produces in a very small amount.
How long would the treatment last? Is it years, or is it indefinite?
It’s usually indefinite in autoimmune hypothyroidism. If someone gets started on thyroid hormone and they’re on a very tiny dose, you can consider taking them off. The typical Hashimoto’s thyroiditis, once someone becomes deficient in the hormone, they either will stay that way or they will progress. It’s very unlikely that they’ll revert back to normal. One point is that the autoimmunity is kind of on a spectrum. So, while most patients become underactive, some become overactive and some people flip between the two. I have patients who become underactive and then they develop this different kind of antibody or autoimmunity where their gland becomes overactive and you know sometimes if we are struggling to deal with it, we may consider removing or destroying the thyroid gland so we can treat the patient with a steady dose. but most people, if they had a clear diagnosis of Hashimoto, clearly low thyroid hormone, we say it’s usually a lifelong replacement.
Are there precautions individuals can take to lower their risk of developing these conditions?
There could be things that we can do to reduce our risk of autoimmunity like a healthy diet and healthy lifestyle. A deficiency of selenium can increase the risk of Auto Thyroid Autoimmunity. Fortunately, again in America, most of the developed world selenium deficiency is rare. So, it has not been found that an excess of selenium will prevent it. But if someone has some weird diet where they cut out a lot of foods, maybe they should go to a more regular diet. But again, that’s a rare deficiency in the U.S. We can also get a selenium supplement over the counter if necessary. We recommend getting screened for other autoimmune conditions so that if someone has one autoimmune condition, say rheumatoid arthritis or type one diabetes autoimmune psoriasis, they’re at risk of other autoimmune conditions.
What are the biggest misconceptions about thyroid conditions and thyroid autoimmune diseases?
There are a few misconceptions. The major one is that thyroid support or iodine supplements will help. If someone has normal thyroid functions, either they have no symptoms or they’ve had the testing done, it’s normal. We should not need to take excess iodine. Most of our diets have enough iodine in them. And I look at it as a benefit risk. If something has little benefit but no risk, I think it’s OK to do. We know that excess iodine can precipitate thyroid autoimmunity. If someone has maybe mild autoimmunity or none, they actually can develop a thyroid condition by trying to take a supplement to prevent it. That’s why some of the supplements may have thyroid hormones in them to also help with weight or metabolism. We know that excess thyroid hormone will lead to some weight loss, but it mostly is muscle mass. And with time it can start affecting our heart. Just like an overactive thyroid would. Those are the reasons to not take thyroid support or iodine supplements without talking to your medical professional.
About Anupam Kotwal, MD
Dr. Kotwal is a physician-scientist actively engaged in research, clinical care and education in the field of benign and malignant endocrine disorders. He received endocrinology training at the Mayo Clinic Rochester. He works closely with the American Thyroid Association on thyroid immune diseases and is a member of the association’s hyperthyroidism guidelines committee.
To learn more, please visit the American Thyroid Association.
