The Complicated Link Between Rheumatoid Arthritis and the Thyroid

Rheumatoid arthritis and the thyroid gland have a complex relationship.

The relationship is so complex that people do not yet fully understand how it works. But it has been found that one autoimmune disorder can increase the risk of developing another, and thyroid function is often depleted because of an autoimmune disorder.

It does not help that symptoms from rheumatoid arthritis can look like hypothyroidism and vice versa, which can present difficulties for patients and the doctors who help them.

More about underactive thyroid glands

Your thyroid is part of the endocrine system, which means that it is part of the system that uses hormones to regulate your body and its functions. When the thyroid is not able to produce as much hormone as it should, the result is called hypothyroidism.

The hormones produced by the thyroid help control your body’s metabolism and the creation of protein. Disrupting this system can have subtle yet devastating effects. You may feel constantly tired or depressed. You may gain weight for no apparent reason, or be similarly constipated.

Hypothyroidism cal also make you sensitive to cold temperatures. In severe cases it can cause your neck to swell into a goiter. This wasn’t an uncommon problem for much of the world until it was discovered that iodine assists your thyroid in functioning properly.

If you have ever wondered why iodine is added to table salt, now you know. That is a cheap and effective method of ensuring that large portions of the population do not become iodine deficient.

However, there is another cause of hypothyroidism that affects even those who consume enough iodine: Hashimoto’s thyroiditis.

Hashimoto’s thyroiditis

Like rheumatoid arthritis, Hashimoto’s thyroiditis is an autoimmune disorder in which your body’s immune system targets the thyroid gland, slowly destroying this important part of your body.

Frustratingly, Hashimoto’s thyroiditis includes iodine intake as one of its risk factors, along with genetics and a lack of selenium in the diet. Viral infections and even certain drugs can trigger it as well.

Lastly, one of the larger factors in developing Hashimoto’s thyroiditis is the presence of another autoimmune disease.

Which brings us back to rheumatoid arthritis.

An autoimmune disorder family

For reasons that are not yet fully understood, autoimmune disorders increase the risk of developing other autoimmune disorders.

One of the biggest potential culprits are genetic factors. The genes which make you susceptible to one autoimmune disease may also make you susceptible to others. Once your immune system has started attacking your body it is more likely to attack your body in another way as well.

Also, the immune system response that is triggered may cause other parts of the immune system to trigger as well.

But the different autoimmune disorders are different, and are treated differently. However, diagnosing these diseases can sometimes be difficult. That is because the symptoms are often similar.

When you have been diagnosed with one autoimmune diseases and a different one flares up, many people put the blame on the diagnosed disease. This can cause the second disorder from being discovered in a timely fashion.

Same symptoms, different causes

As you read them above, did any of the hypothyroid symptoms seem familiar to you?

Tiredness is a symptom that is common to both hypothyroidism and rheumatoid arthritis. In hypothyroidism it can be just the first hint that something is wrong with your thyroid gland, but since you already have RA, the proper cause for the symptom may not be discovered until more damage has been done.

But that is not the only symptom common to RA and hypothyroidism. One of the hallmarks of rheumatoid arthritis, swollen joints, can also be a result of an underactive thyroid. Weight gain is another similarity, as is a constant yet low level of pain in your muscles.

These similarities in symptoms pose a problem. That is because while the symptoms may be similar and the causes may both be autoimmune disorders, the treatments are different.

While RA holds the spotlight, the hypothyroidism continues to bring your body down.

Thankfully, treatments for autoimmune hypothyroidism and rheumatoid arthritis are compatible. Once your doctor has sussed out the second disease treatment can proceed without affecting your RA medication and treatment regiment.

Detecting additional autoimmune disorders

The good news is that despite the difficulty in detecting a second autoimmune disease in the presence of another one, it is still possible.

Conclusive tests have to come in the form of a blood test. This is especially useful for when hypothyroidism is hiding underneath rheumatoid arthritis but can be useful when the inverse is true as well.

There are some things you can do yourself to keep an eye out for a potential second autoimmune disorder.

Watching your own symptoms

Rheumatoid arthritis has a laundry list of potential symptoms: fatigue, fever, swollen and painful joints, stiffness and muscle pain, heart and lung issues from inflammation, constipation or diarrhea, and even anxiety and depression.

Proper treatment can help control most of these symptoms. If you keep in mind the fact that the treatment for RA does not necessarily help hypothyroidism and monitor your symptoms then you should be able to notice if your symptoms are not responding properly to the treatment.

This could be your sign that the rheumatoid arthritis has had an influence on your thyroid.

Not all RA symptoms overlap with hypothyroidism. For example, patients with RA are more likely to experience unwanted weight loss rather than unexpected weight gain.

This weight gain is one of the more obvious symptoms of hypothyroidism, especially when it occurs alongside more fatigue than usual.

If you do develop autoimmune hypothyroidism alongside your rheumatoid arthritis, it is important to catch the new disease as fast as possible. This is not only to manage those symptoms but also to protect your heart.

Rheumatoid arthritis, hypothyroidism, and heart disease

Starting with rheumatoid arthritis puts your heart at risk in two ways.

The first is because of the effects of RA itself. RA can affect the area around you heart with inflammation, which can lead to scarring. It can can also inflame and damage the arteries connected to your heart.

The second way RA puts your heart at risk is because of the increased chance of autoimmune hypothyroidism.

Hashimoto’s thyroiditis also has its own ways of potentially damaging the heart, and they are different from rheumatoid arthritis.

It can influence your levels of low-density lipoproteins, the “bad” cholesterol that can contribute to heart disease. Thyroid hormones are also involved in controlling your heart’s function. This can enlarge your heart and potentially lead to heart failure.

Generally, the more autoimmune conditions you have, the more susceptible you are to heart disease. This makes it all the more important to catch and treat all autoimmune disorders your body may develop.

Final thoughts

Rheumatoid arthritis is an autoimmune disorder. Something about the way autoimmune disorders work, possible a genetic component or sensitization of the immune system, makes your body more likely to develop a second autoimmune disease.

In many cases, this second autoimmune disorder is a form of hypothyroidism, especially Hashimoto’s thyroiditis. Any form of underactive thyroid can be difficult to discover alongside rheumatoid arthritis because they share common symptoms.

However, diagnosing the second disease is still important. Treatment is different yet can happen at the same time, and not treating both disorders can lead to irreparable harm.

References

https://www.everydayhealth.com/rheumatoid-arthritis/living-with/ra-and-your-thyroid-function/

https://www.webmd.com/women/hypothyroidism-underactive-thyroid-symptoms-causes-treatments

https://www.mayoclinic.org/diseases-conditions/hashimotos-disease/symptoms-causes/syc-20351855