
Rheumatoid arthritis is a systemic disease characterized by painful, swollen, inflamed joints. It can occur at any time from infancy on, affecting not only particular joints and muscles, but in extreme cases, vital organs as well. It most commonly occurs between the ages of 20 and 35, with women three times as vulnerable as men until the age of 50, when the difference narrows. Of the 6.5 million Americans affected, about one-third are free of symptoms for long periods of time; of the children with juvenile rheumatoid arthritis, two-thirds recover completely by adulthood.