Below are 6 possible reasons why a person with RA experiences chronic fatigue. These underlying factors may work alone or together to contribute to an individual’s overall fatigue.

1. Inflammation

Researchers are continuing to learn about the connections between rheumatoid arthritis inflammation and fatigue. Evidence suggests inflammation may trigger fatigue, and reducing inflammation may help reduce fatigue in some cases.

However, fatigue often persists even when blood tests for C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) indicate inflammation levels are normal. Some experts speculate that either fatigue and inflammation are independent of one another or that other, possibly yet-to-be-discovered inflammation markers—alternatives to CRP and ESR—may be better indicators of RA disease activity and fatigue.

2. Joint pain

Many experts argue that joint pain, not inflammation, is the main trigger of RA fatigue. Joint pain and fatigue are often in sync, and they can be present even when blood tests show normal levels of inflammation. However, it’s also possible to experience fatigue without joint pain.

When fatigue is present even after inflammation and pain have been successfully treated, there may be another factor at work.

3. Sleep apnea

People with rheumatoid arthritis may be up to 75% more likely than others to have Sleep apnea is a sleep disorder in which breathing repeatedly stops and starts during sleep. It affects how much oxygen your body takes in, and it can leave you feeling tired even after a full night’s sleep.

Sleep apnea does not seem to be related to RA inflammation, which may help explain why fatigue can persist even when other RA symptoms are well-controlled. Thankfully, sleep apnea can be diagnosed and treated. Treatment typically includes using a continuous positive airway pressure (CPAP) machine or another treatment device to increase oxygen intake while sleeping.

4. Mental health issues

People with rheumatoid arthritis are more likely to be coping with mental health issues that are linked to fatigue. RA, depression, and fatigue are known to be closely linked. Stress, anxiety, and other mood disorders may be connected to fatigue, too.

It’s not totally clear that mental health issues cause fatigue directly. It may be that people struggling with issues like depression and anxiety are more likely to have trouble sleeping.8In addition, some anti-depressant and anxiety medications list drowsiness as a side effect. More research is needed in this area.

5. Anemia

Researcher suggests up to 70% of people with rheumatoid arthritis have anemia. This condition is associated with low iron levels and fatigue.

Anemia has many possible causes. For example, you may not be eating enough iron-rich foods. Certain medical conditions and medications can cause changes to your gastrointestinal tract lining, affecting the body’s ability to absorb iron. A physician can work with you to identify the underlying cause and recommend treatment.

Not all experts believe that anemia is a significant cause of fatigue in people with RA.

6. Medication side effects

While medications are valuable tools for treating RA, many can cause fatigue. For example, methotrexate can cause fatigue. Other medications may not cause fatigue directly but may increase your risk for depression, weakness, or insomnia, all of which may contribute to fatigue. A doctor or pharmacist can tell you if your medication—or combination of medications—may cause fatigue.

Tell your physician about your fatigue

In addition to the 6 items listed above, other factors can contribute to fatigue, such as vitamin B12 and D deficiencies, thyroid problems, and infections. Determining the underlying cause of fatigue is not an easy task for doctors or patients. The more information you give your physician about your fatigue and how it affects your life, the better the chance that, together, you can take steps to alleviate it.