How are depression and chronic pain linked?

Scientists don’t yet know how depression and chronic pain are linked, but the illnesses are known to occur together. Chronic pain can worsen depression symptoms and is a risk factor for suicide in people who are depressed.²

Bodily aches and pains are a common symptom of depression. Studies show that people with more severe depression feel more intense pain. According to recent research, people with depression have higher than normal levels of proteins called cytokines.⁴ Cytokines send messages to cells that affect how the immune system responds to infection and disease, including the strength and length of the response. In this way, cytokines can trigger pain by promoting inflammation,⁵ which is the body’s response to infection or injury. Inflammation helps protect the body by destroying, removing, or isolating the infected or injured area. In addition to pain, signs of inflammation include swelling, redness, heat, and sometimes loss of function.

Many studies are finding that inflammation may be a link between depression and illnesses that often occur with depression. Further research may help doctors and scientists better understand this connection and find better ways to diagnose and treat depression and other illnesses.

One disorder that has been shown to occur with depression is fibromyalgia.⁶ Fibromyalgia causes chronic, widespread muscle pain, tiredness, and multiple tender points—places on the body that hurt in response to light pressure.⁷ People with fibromyalgia are more likely to have depression and other mental illnesses than the general population. Studies have shown that depression and fibromyalgia share risk factors and treatments.⁷

---

Previous: What is chronic pain? Next: How is depression treated in people who have chronic pain?