Rheumatoid arthritis is an autoimmune disease that causes pain and inflammation in joints. It affects about 1.3 million Americans, according to the Arthritis Foundation. Onset of RA most often occurs in the 20s and 30s, and disproportionally affects women. Roughly 30 to 60 percent of patients with RA are also anemic, according to the Society for the Advancement of Blood Management. Individuals with a certain types of anemia are often deficient in vitamin B-12.
Rheumatoid Arthritis and Anemia
Rheumatoid arthritis is a known cause of aplastic anemia, according to the Heart, Lung and Blood Institute. Experts have been aware of the link between pernicious anemia and the autoimmune joint disease since at least the 1970s. Both types of anemia, like RA, are autoimmune disorders and can lead to vitamin B-12 malabsorption. The Aplastic Anemia and MDS International Foundation explains that low vitamin B-12 levels reduces the production of blood cells, which leads to a drop in the number of platelets as well as red and white blood cells.
Anemia and B-12
The National Institutes of Health reports that people with certain types of anemia usually require lifelong vitamin B-12 replacement, often in the form of injections. Anemia can cause destruction of stomach cells by the body’s own defense system, according to the Linus Pauling Institute. Without treatment, the condition can lead to decreased secretion of acids and enzymes necessary for absorbing vitamin B-12. In order to restore B-12 levels in the blood, patients need intramuscular injections that bypass the intestines.
In a 1997 study published in the journal “Arthritis and Rheumatism,” researchers found that patients with RA who were not on the drug methionine had higher levels of homocysteine in their blood. Homocysteine is an amino acid that, in large concentrations, could cause artery damage and increase the risk of blood clots. Those taking the drug had normal blood levels of the amino acid. Vitamin B-12 shots, along with other B vitamins, could reduce the risk of cardiovascular mortality in a subgroup of patients with RA. Death from heart disease is 50 percent higher in RA patients compared with other populations, according to a 2008 study published in the same journal.
Dose of B-12
Rheumatoid arthritis patients with anemia need more than the 2.4 micrograms of vitamin B-12 recommended for healthy adults. For these individuals, a 1-milligram dose can provide therapeutic effectiveness. For those who would rather take an oral vitamin, oral vitamin B-12 is likely to be just as effective as an intramuscular injection. A combination of 400 international units of vitamin B-12, along with 1 milligram of folic acid and 10 milligrams of vitamin B-6 significantly decreased homocysteine levels in coronary patients, according to 2002 study published in the “Journal of the American Medical Association.”