What is rheumatoid arthritis?
Rheumatoid arthritis (RA) is a long-term inflammation affecting several joints. According to Switzerland's Federal Office of Public Health (FOPH), it is an autoimmune disease: the immune system mistakenly attacks the thin lining inside the joints (the synovium, a thin layer that lubricates and nourishes the joint), which swells and becomes painful.
According to the Swiss League against Rheumatism, about one person in 200 is affected, close to 45,000 people in Switzerland, and women about three times as often as men. The causes are not fully understood: heredity, hormones, infections, environment and diet are among the factors studied.

