Hypothyroidism and RA
Some things run in my family: brown hair and hazel eyes, a love of reading and travel, and autoimmune conditions. My family tree is laced with type I diabetes, hypothyroidism, psoriasis, and rheumatoid arthritis. In fact, the frequency of autoimmune conditions among my relatives actually led to my first diagnosis.
Over the past 30 years, my sister has been diagnosed with all of the conditions I listed. A scientist from the start, she was actually the one to first notice the swollen lump in my throat. Only 11 years old, she pointed to it and said to our mom, “I think Tamara has a goiter.” Her precocious assessment was confirmed by an endocrinologist, who concluded that I did indeed have a goiter caused by autoimmune thyroiditis.
What is hypothyroidism?
Also known as Hashimoto’s disease, autoimmune thyroiditis occurs when the immune system attacks the thyroid gland, causing it to produce reduced levels of thyroid hormone. This is similar to rheumatoid arthritis in that the immune system is mistakenly targeting healthy parts of the body instead of solely fighting germs and viruses. Thyroid hormones play a major role in regulating our metabolism and energy level.
Symptoms of hypothyroidism
When the thyroid gland is underactive, this is called “hypothyroidism,” and results in symptoms such as fatigue, weight gain, feeling cold, depression, and decreased libido, among others.1 Hypothyroidism may or may not result in a goiter, which is an enlarged thyroid gland that can be pronounced enough in size to be visible on the throat.
Treatment of hypothyroidism
The treatment for hypothyroidism is life-long and consists of synthetic hormone replacement in the form of a daily pill such as synthroid or levothroid. It is important for people with hypothyroidism to receive routine check-ups with an endocrinologist to ensure their hormone levels remain in normal range, as medication dosage may need to be adjusted over time.
The connection between hypothyroidism and RA
Not only do my sister and I both have autoimmune thyroiditis, but we also both have RA. It turns out that’s no coincidence, as there is indeed a connection between these autoimmune conditions. In one study, 24% of RA patients also had hypothyroidism, compared with 4.6% of the general population.2 Another study examined the health records of thousands of patients with autoimmune conditions, and found that people with RA or autoimmune thyroiditis are at an increased risk of developing both conditions at some point in their lives.3
How does hypothyroidism affect RA?
While having multiple diagnoses of autoimmune conditions can leave me feeling like my immune system has completely run amuck, managing hypothyroidism has proven far more straightforward than treating RA. Unlike rheumatoid arthritis, I do not experience sudden, unexpected flare-ups of hypothyroid symptoms. On the occasions when my thyroid levels are off, the onset of symptoms is slow and gradual. With awareness, I can pick up on this before the symptoms become too pronounced, enabling me to have my levels tested and my medication adjusted before the condition causes much disruption in my life. Unlike RA, I have never experienced symptoms from Hashimoto’s that did not go away with dosage changes in my medication.
Fatigue is a common symptom in hypothyroidism and RA
That being said, one complicating factor is that fatigue is a symptom common to both hypothyroidism and RA, which can make it difficult to determine which condition is causing the fatigue. Having regular check-ups with both my rheumatologist and endocrinologist has been essential in differentiating RA-fatigue from hypothyroidism-fatigue. For this reason, I have always opted to be treated for Hashimoto’s by an endocrinologist, rather than by my primary care doctor. While seeing a gland specialist is a little more expensive and time-consuming than a visit to my primary care physician, I feel more confident about disease management when working with an expert.
Generally, my thyroid levels remain quite stable, and I only need to visit the endocrinologist on a yearly basis. On the occasions when he does alter my dosage, I return a few weeks later to repeat level testing to ensure that the new medication strength is appropriate. I was initially diagnosed with autoimmune thyroiditis at the age of eight, and my prescription required frequent adjustment as I proceeded through a series of growth spurts.
Thyroid fluctuations during pregnancy
Since adulthood, my levels have rarely needed to be changed, with the exception of during my two pregnancies. I experienced quite a bit of thyroid fluctuation while pregnant, and therefore my endocrinologist requested that my OBGYN test my thyroid levels and send him the results at each of my monthly prenatal check-ups. Weight gain can impact the body’s need for thyroid, as a larger body mass generally requires a higher dosage of synthetic hormone. At times when my weight has fluctuated, I have needed a corresponding change in medication.
Monitor thyroid levels
As people with RA are more likely to develop autoimmune thyroiditis than the general population, and as the symptom of fatigue can easily be attributed to RA when it may actually be stemming from hypothyroidism, it is recommended that people with rheumatoid arthritis have their thyroid function and hormone levels regularly screened via testing TSH and free thyroxine (T4) levels.4 This ensures that symptoms caused by hypothyroidism are not incorrectly attributed to RA.
Furthermore, hypothyroidism carries an increased risk of cardiovascular disease5, and patients with both autoimmune thyroiditis and rheumatoid arthritis are at an even higher risk for heart problems.6 Therefore, receiving treatment for both conditions is important in limiting the risk of additional complications.
When was your last flare?