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Imagine you’re enjoying a leisurely walk in nature. Suddenly, you trip, twisting your ankle. Ouch! Right away, you notice your ankle swelling up. Inflammation, in this case, is a good thing. It is your body’s way of protecting your tissues, allowing them to heal from your injury.
Sometimes, inflammation occurs inside your body. And you don’t need an injury like a fall to start the inflammatory process. Chronic inflammation inside the body can lead to health problems, including ones related to your thyroid.
So, how do you know if you have ongoing chronic inflammation inside the body? Keep reading to learn more about a biomarker for inflammation, c-reactive protein -- known as CRP -- and what chronic inflammation could mean for you as a hypothyroid patient.
Chronic inflammation tends to get a bad rap, and rightfully so. Inflammation that lasts a long time in the body damages your healthy tissues. That damage to your healthy tissues can also be irreversible and cause further health complications.
Unlike an acute injury, there isn’t always an obvious trigger for chronic inflammation. Sometimes, inflammation may start as acute but never resolve. It may also take time for you to notice symptoms of chronic inflammation, making it hard to pinpoint the trigger. Chronic inflammation occurs due to:
- Chronic infection
- Autoimmune diseases, such as lupus or inflammatory bowel disease
- Repetitive injury or irritation, such as smoking
Symptoms often depend on the location of the chronic inflammation. For example, those living with Hashimoto’s thyroiditis (chronic inflammation of the thyroid) may have symptoms related to a slow metabolism. In contrast, chronic inflammation of the lungs would have breathing-related symptoms.
So, remember, acute inflammation after an injury is good; chronic or long-lasting inflammation is harmful. Besides symptoms, how do you know if you have ongoing inflammation inside the body? This is where measuring blood levels of inflammatory biomarkers comes in.
C-reactive protein (CRP) is an inflammatory marker produced by your liver in response to inflammation in the body. The CRP blood test helps show whether you have inflammation in your body. But, it doesn’t tell your provider the cause of the systemic inflammation or localized issues.
High levels of CRP in the blood can indicate various health conditions, including infections, autoimmune disorders, and chronic diseases. Here are some common conditions that can cause elevated CRP levels:
- Autoimmune disorders: Conditions like Hashimoto’s thyroiditis, rheumatoid arthritis, lupus, diabetes mellitus, and inflammatory bowel disease can cause the immune system to mistakenly attack healthy tissues, leading to chronic inflammation and high CRP levels.
- Chronic diseases: Chronic conditions like hypothyroidism, cardiovascular disease, diabetes, and obesity can also trigger inflammation in the body, resulting in elevated CRP levels. High CRP levels in these cases can indicate an increased risk of complications and disease progression.
- Cancer: Some types of cancer, such as lymphoma and multiple myeloma, can cause inflammation in the body and lead to high CRP levels. Monitoring CRP levels in cancer patients can help assess disease progression and treatment efficacy.
- Trauma or surgery: Injuries, trauma, or surgical procedures can also cause inflammation in the body, leading to elevated CRP levels as the immune system responds to tissue damage.
- Chronic stress: Prolonged stress can trigger inflammation and increase CRP levels in the blood. Managing stress through stress-reducing techniques like exercise, meditation, and therapy can help lower CRP levels and improve overall health.
When CRP levels are low, it means minimal to no inflammatory processes are happening in your body. Other than during an acute injury or illness, a low CRP level is a good thing. But following an injury or infection, CRP levels increase. That’s because your liver releases more CRP in response to the injury or infection. So, it makes sense that elevated c-reactive protein levels are higher after an injury, as an injury or infection often goes hand in hand with inflammation.
There are two types of CRP tests: regular and the high-sensitivity c-reactive protein test. A highly sensitive CRP (serum Hs-CRP levels test) detects small changes in serum CRP levels and is often used to determine your cardiovascular risk factors. While not generally used to measure overall inflammation, it can be.
To recap, we know that high CRP levels mean inflammation is occurring somewhere in the body. But what does that have to do with your thyroid function?
Thyroiditis is a term that means inflammation of your thyroid gland. Thyroiditis can cause
- Underactive thyroid (hypothyroidism)
- Overactive thyroid (hyperthyroidism)
- Temporary hyperthyroidism followed by hypothyroidism
Not all cases of thyroiditis are permanent and need medication management. Some cases resolve on their own. There are many types of thyroiditis, some of which we will discuss below. Let’s look at four thyroid disorders where a high CRP level seems to play a role in your thyroid function.
Subacute thyroiditis
Subacute thyroiditis (SAT) most frequently occurs after a viral infection. It can cause a variety of symptoms including:
- Thyroid or neck pain
- Fever
- Goiter
- Difficulty or pain while swallowing
- Hoarseness
Beyond these initial symptoms, SAT disrupts the thyroid’s usual function. SAT does this by altering thyroid hormone levels and thyroid iodine uptake. Since iodine is essential for producing thyroid hormone, insufficient levels can lead to a gradual decline in thyroid hormone levels. While SAT often resolves on its own, 5 to 27% of cases progress to hypothyroidism.
A recent study uncovered a connection between the development of hypothyroidism after SAT. Those with significant changes in CRP, thyroid-stimulating hormone (TSH), and thyroid hormone levels during SAT were more likely to develop hypothyroidism. A TSH level assesses how well your thyroid functions.
The findings highlight two major risk factors for developing hypothyroidism after SAT: a high CRP level, especially higher than 90, and a low TSH level. Severe inflammation, as shown by a high CRP level, can impact thyroid function. As a result, TSH levels would drop.
Hashimoto’s thyroiditis
Hashimoto’s thyroiditis is an autoimmune thyroid condition. An autoimmune disorder results from the body’s immune system attacking healthy tissues. In the case of Hashimoto’s, the immune system attacks thyroid tissues, resulting in damage and reduced thyroid function. Ongoing attacks on the thyroid result in chronic inflammation due to the presence of thyroid antibodies - TPO (thyroid peroxidase) and Tg (thyroglobulin).
A study analyzed CRP, TSH, and thyroid antibody levels in hypothyroidism patients. Results showed a connection between elevated CRP levels and TG antibodies. However, the degree of elevation of CRP levels did not correlate with the severity of hypothyroidism. It is important to note that this study used a high-sensitivity CRP lab test.
Unlike other types of thyroiditis, overt Hashimoto’s thyroiditis doesn’t usually go away on its own. And if Hashimoto’s has led to hypothyroidism, you will need life-long treatment with thyroid hormone medication.
Postpartum thyroiditis
Postpartum thyroiditis is another autoimmune thyroid disorder. It can result in temporary or permanent thyroid impairment. But, permanent hypothyroidism occurs in 15 to 50% of those with postpartum thyroiditis. Postpartum thyroiditis occurs within one year of pregnancy.
While rare in the general population, those with a family history of a thyroid disorder or another autoimmune disorder appear to be at a higher risk. And if you develop postpartum thyroiditis after one pregnancy, you’ll likely develop it with each pregnancy.
Nearly half of those with postpartum thyroiditis have symptoms of hypothyroidism. Six months after childbirth, those with hypothyroidism from postpartum thyroiditis had high Hs-CRP and TSH levels. TPO-antibodies were only slightly elevated.
Note that this study only evaluated 14 people, so the results require more analysis. And the study doesn’t predict whether high CRP levels will cause hypothyroidism.
Subclinical hypothyroidism
Subclinical hypothyroidism is a mild form of hypothyroidism. It is often characterized by a minor elevation in TSH but with normal thyroid hormone levels. This contrasts with overt hypothyroidism, where the TSH level is high, and thyroid hormone levels are low. Those with subclinical thyroid dysfunction may or may not have symptoms of hypothyroidism.
Subclinical hypothyroidism is characterized by higher markers of inflammation, including CRP, according to a 2015 study. Furthermore, a higher CRP level correlated with alterations in TSH levels. But, this study doesn’t determine whether those with subclinical hypothyroidism and elevated CRP levels go on to develop overt hypothyroidism.
With all the harmful effects of chronic inflammation, you may wonder how to decrease inflammation in your body.
Remember, acute inflammation after an injury or infection generally resolves on its own. And CRP, an inflammatory biomarker, will lower as the underlying cause resolves.
On the other hand, chronic inflammation -- including low-grade inflammation -- often doesn’t go away without external management, including medications. Steroids like prednisone can help manage inflammation, especially for SAT. But you shouldn’t take steroids long-term.
If Hashimoto’s thyroiditis is the cause of your chronic systemic inflammation and you have hypothyroidism, taking thyroid hormone medication can help. Not only does it increase thyroid hormone levels, but it also lowers Hs-CRP to within a normal range, according to a 2014 study. Less inflammation can help reduce thyroid tissue destruction.
Besides medication management, lifestyle changes can reduce the inflammatory process. You can try:
- Participating in regular physical activity
- Eating a balanced diet rich in anti-inflammatory food
- Watch your weight
- Avoid tobacco smoke or exposure to it
Chronic inflammation, as shown by high serum CRP levels, can lead to health problems, even with your thyroid. If you suspect an ongoing inflammation, ask your provider about testing your serum CRP levels as well as your thyroid levels.
You need a blood test to evaluate your thyroid levels. But, with new at-home testing kits, such as Paloma’s Health Complete Thyroid Test, hypothyroid patients can test thyroid function from home. A finger prick blood sample is all that is needed to measure the three most common thyroid biomarkers to determine your thyroid function. Suppose your results do show an underactive thyroid. In that case, our thyroid specialists are ready to help you develop your treatment plan. Our personalized, holistic approach to managing hypothyroidism sets us apart from other thyroid providers.