- Rheumatoid arthritis affects women two to three times as often as men.
- Rheumatoid arthritis can begin at any age, but most often begins between the ages of 40 and 60.
- While rheumatoid arthritis occurs in all racial and ethnic groups, over 5% of certain Native Americans (the Chippewa and Pima Tribes) have the disease.
It tends to be worse in smokers than
in nonsmokers.
The only known risk factor for
rheumatoid arthritis is a possible inherited factor in some families (genetic predisposition). A genetic
factor may affect how the immune system
functions, causing inflammation and eventual destruction of the membranes
lining the joints.