Many people don’t know that having psoriasis and/or psoriatic arthritis (PsA) is linked to a higher risk of other autoimmune conditions. Researchers think that having psoriasis or PsA specifically increases your risk for autoimmune thyroid disease and subclinical hypothyroidism. If you have psoriasis or PsA, what do you need to know about your risk of thyroid disease? What are the symptoms? And what sort of thyroid screening should you have? Here’s what you need to know.
About Psoriasis and PsA
Psoriasis symptoms include inflamed, red skin patches, often covered with scales. The affected skin may burn or itch. These most common locations for psoriasis outbreaks are the elbows, knees, scalp, neck, hands, feet, and in some cases, the fingernails. Many cases of psoriasis are relapsing and remitting, meaning that symptoms come and go over time.
The symptoms of psoriatic arthritis include the skin-related symptoms of psoriasis, along with fatigue, and pain, swelling, and stiffness. Psoriasis commonly affects joints in your ankle, knees, fingers, toes, and lower back. Tendons can also become inflamed and sore. Some people with PsA develop dactylitis, which can make your fingers or toes swell and give them a sausage-like appearance. In some cases, your eyes can become red and inflamed, or you may have a conjunctivitis infection."
Psoriasis and PsA are autoimmune conditions. With autoimmune conditions, your body mistakenly attacks itself. In psoriasis, the immune system attacks skin cells. In PsA, your joints and tendons are also attacked along with the skin.
According to the American Autoimmune Related Diseases Association, there are more than 100 conditions classified as autoimmune, affecting an estimated 50 million Americans. Having any autoimmune disease puts you at an increased risk of other autoimmune conditions.
Psoriasis, PsA, and Thyroid Disease
While researchers have studied connections between psoriasis/PsA and other autoimmune diseases, a late 2018 study published in the Journal of the American Academy of Dermatology found that having psoriasis and PsA increases the risk of developing autoimmune Graves’ disease and Hashimoto’s thyroiditis. The risk was even greater for patients with PsA.
As with many autoimmune disease issues, researchers haven’t yet determined the explanation. But they theorize that genetic and immune system irregularities common to both diseases may link psoriasis/PsA and autoimmune thyroid disease.
Based on their findings, the study authors recommended increased physician awareness of the risks. They also advised thyroid screening for patients with psoriasis and PsA, and for those psoriasis/PsA patients who have thyroid symptoms.
What Are Your Next Steps?
If you have psoriasis or PsA, you should familiarize yourself with the symptoms of the two key autoimmune thyroid diseases and the conditions they cause:
- Hashimoto’s thyroiditis and the resulting hypothyroidism
- Graves’ disease and the resulting hyperthyroidism
Common symptoms of Hashimoto’s and hypothyroidism include fatigue, weight gain, depression, hair loss, constipation, puffiness, hoarseness, neck discomfort, and brain fog. Common symptoms of Graves’ disease and hyperthyroidism include insomnia, weight loss, anxiety, diarrhea, neck enlargement (goiter), muscle weakness, and eye and vision problems.
If you have psoriasis/PsA and notice any of these symptoms, your first step should be a complete thyroid screening and evaluation. This should include:
Your physician may also order a thyroid ultrasound to check for the thyroid enlargement or shrinkage commonly seen in autoimmune thyroid disease.
Of special interest to women with PsA: a recent study looked at women with PsA who were at higher risk for thyroid disease – defined as having a TSH level in the upper limit of the reference range. The study authors recommended that these women receive regular screening for thyroid problems, including TSH and TPOAb blood tests, and a thyroid ultrasound. If you are a woman with PsA, talk to your physician about scheduling periodic thyroid screening.
An Important Note for Patients With Psoriasis/PsA and Graves' Disease
If you have psoriasis/PsA and are diagnosed with Graves’ disease, be aware that some drug treatments can worsen your psoriasis. Specifically, beta blockers like propranolol (Inderal) or atenolol (Tenormin) – used to treat elevated heart rate and other symptoms of Graves’ disease – can worsen psoriasis in about 25 to 30 percent of patients.
If You Have Autoimmune Thyroid Disease
If you have Hashimoto’s thyroiditis or Graves’ disease, your risk of developing another autoimmune disease is increased. As a result, it’s important to become knowledgeable about the common signs and symptoms of other autoimmune conditions. These include fatigue, muscle and joint pain and/or swelling, digestive problems, dry eyes, brain fog and difficulty concentrating, and skin rashes. If you have symptoms that continue after optimal thyroid treatment, you should discuss them with your doctor.
There’s also a caution if you have Graves’ disease and are being treated with a beta blocker. While most Graves’ disease patients are not given beta blockers for extended periods, long-term (one year or more) beta blocker use is associated with a significantly increased risk of developing psoriasis.