Rheumatoid Arthritis: A Neurological Disease?

For more than a century, there’s has been a puzzle in rheumatology. Why is it that so many people with inflammatory arthritis get symmetrical involvement of their joints? It is very common for people to get exactly the same joints involved in both hands or in both feet.

Sometimes joints get affected by arthritis because they have already been subjected to a lot of wear and tear: that’s thought to be one of the reasons why gout most often affects the big toe. But the symmetrical pattern of arthritis is far more difficult to understand. There has been speculation for at least 30 years that this symmetry indicates neurological involvement in the disease, and there was a stimulating paper on the topic seventeen years ago, and it has been known for some time that artificially induced arthritis in one joint produces inflammatory changes in the same joint on the other side of the body.

Now investigators from the University of California at San Diego School of Medicine have published an important discovery. Rheumatoid arthritis drugs work better, at least in arthritic rats, when delivered into the central nervous system. Rheumatoid arthritis (RA) is a disease in which there is chronic inflammation, leading to joint pain and destruction. Pain and inflammation in the joints are constantly monitored by the central nervous system, and we have known for many years that the nervous system can regulate inflammation and immune responses. It was demonstrated in the 1960s that damage to certain regions in the hypothalamus of the brain could impair the work of the immune system. The scientists from San Diego focused on a protein called p38, which is involved in a number of cellular processes critical to the development of RA. Several substances that block the action of p38 are effective in animal models of arthritis and are currently being tested in clinical trials in patients with RA.

Pain and inflammation activate p38 in the brain and spinal cord, and blocking it by introducing medicines directly into the central nervous system reduces inflammation in joints.

This is important research, because it opens up new possibilities for treating an illness that can often be very difficult to treat. It may also help explain another observation. Some patients with rheumatoid arthritis who are treated with acupuncture get a reduction in joint symptoms and sometimes even repair of some of the damage to the cartilage in their joints. Experienced acupuncturists see this in about a third of patients whom they treat, so it was a surprise to see a review claiming that acupuncture did not help RA. If we see a disconnect between clinical observation and a research study, there are two options: either clinicians are deluding themselves or there’s something wrong with the research method. Interestingly, there’s recently been a great deal of discussion about the kind of research methodology that produced this negative result, prompted by a very interesting and challenging paper.

My conclusion? Acupuncture may indeed be a valuable adjunctive treatment for RA. But whether it will work on its own remains less certain.

And the best approach of all is to address the physical, psychological, social, subtle and spiritual dimensions of a person with RA. In other words, the new form of Integrated Medicine that I describe in Healing, Meaning and Purpose.