Chronic Inflammation and The Sickness Response

Recent studies now show an exciting connection between chronic inflammation and the accompanying withdrawal, depression, anxiety and lack of energy frequently seen in what the workers compensation system calls ‘malingerers’. Scientists have long called this set of symptoms ‘the sickness response’ and understood it to be a set of motivational behaviors. But latest research reveals it comes from an actual set of physiological processes summarized in Pathology and Intervention in Musculoskeletal Rehabilitation, 2nd Edition. The following information comes from the chapter Repetitive Stress Pathology: Soft Tissue by Nancy N. Byl, Mary F. Barbe, and Jane Fedorzyck.

Chronic inflammation in the muscles and soft tissues produces a very specific set of chemical reactions. One of these is cytokine, which scientists now believe is the molecular signal of sickness. This is your immune system run amok, and chronic inflammation can definitely be a precursor. It becomes systemic when, during the inflammatory phase of the healing process, cells literally open up to receive more blood and oxygen to heal, and empty out debris. Blood vessels can be transversed in this process, sending chemicals meant to kill injured cells, into the rest of the body, causing widespread inflammatory effects, such as tissue damage and fibrosis in healthy tissues.

Functional declines ensue throughout the body and cytokine; one of the chemicals released cues the brain that the body is sick. The immune system then puts the body into state where minimal energy is expended so it can fight the sickness. The vagus nerve, one of the longest in the body traveling from the cranium to the abdomen, is the information superhighway for this sickness response. The vagus nerve works with the parasympathetic nervous system to control your heart and lungs. Recent studies have led researchers to believe it has a possible role in depression and other mood disorders as well. Other studies have shown blocking this nerve reduces the pain threshold, one specifically in women who reported work-related forearm and hand symptoms. The authors believe these studies show “a relationship between repetitive and forceful task demands and induction of the sickness response”.

These studies provide some defense against the stigmatization that often comes with patients who report vague symptoms, which are then attributed to psychological complaints. So if your doctor tells you it's all in your head, direct him or her to this book Pathology and Intervention in Musculoskeletal Rehabilitation, 2nd Edition, and the chapter Repetitive Stress Pathology: Soft Tissue by Nancy N. Byl, Mary F. Barbe, and Jane Fedorzyck.

@JillGambaro is the author of The Truth About Carpal Tunnel Syndrome . She has lived with multiple repetitive strain injuries known as a “double crush” for over 15 years. A former board member of the Los Angeles Repetitive Strain Injury Support Group and the Cumulative Trauma Disorders Resource Network, Jill advocates for prevention, patient engagement and healthy playing for musicians through her Blog, Facebook and Twitter @IckyFingersMovi. Look for her upcoming documentary Icky Fingers.