Arthritis affects 54.4 million US adults, about 1 in 4. It is a major cause of work disability in the United States and one of the most common chronic conditions in the nation. Arthritis is a common cause of chronic pain. Chronic pain caused by arthritis affects millions of people in the United States every year. About one in four adults with arthritis—15 million people—report experiencing severe joint pain related to arthritis.  Additionally, nearly half of adults with arthritis have persistent pain.