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 that line the joints.

Other factors that may influence your risk of developing rheumatoid arthritis include:

• Being female. rheumatoid arthritis affects women 2 to 3 times as often as men.⁴
• Being between the ages of 40 and 60. rheumatoid arthritis can begin at any age, but it most often begins in adulthood.¹