Cases of rheumatoid arthritis (RA), a form of joint degeneration related to autoimmune function, have gone up in women in recent years, affecting 9.8 per 1,000 American women in 2005. Men are diagnosed at a rate of 4.1 men per 1,000. These numbers represent just under 1% of the population. The disease can strike at any age but most people are in their 60s when RA begins.

What is rheumatoid arthritis?

Although RA’s origin is unknown, the body’s immune system influences inflammation in the synovium, the protective capsule that surrounds the joints where two bones meet. The capsule, filled with lubricating synovial fluid, produces excess fluid, causing swelling and enlargement of the joint. Abnormal growth of fibrous tissue in the synovium contributes to the deformity and enlargement of affected joints. As deformity of the synovium progresses, the bones of the joint begin to erode and cartilage thins under increasing pressure. Diagnosis of RA usually comes when five or more joints are affected.

Three types of RA

Rheumatoid arthritis usually affects a patient in one of three general ways although each case is unique:

1. Monocyclic — An inflammatory episode occurs just once but can last as long as five years. This form doesn’t recur after remission.
2. Polycyclic — Episodes come and go over the course of disease, affecting different joints at different levels of intensity.
3. Progressive — Once disease begins, there are no remissions. Symptoms continue progressively, with increasing intensity, and no remissions.

Risk factors

Genetics are thought to play a role in RA development, as are environmental exposures to toxic chemicals and microbes. Two risk factors said to be modifiable are cigarette smoking and a woman’s reproductive history. Three of every four RA patients is or was a cigarette smoker.

Several factors associated with the female reproductive cycle influence risk:

• Use of oral contraceptives (OCs) may reduce risk; this link is especially notable in women taking the stronger doses of OCs on the market in the 1960s and 1970s.
• Women with a history of irregular menstrual cycles or early menopause are at increased risk for RA.
• Women who never have a live birth face increased risk.
• Many RA patients enjoy a welcome easing of symptoms during pregnancy.
• Breastfeeding reduces risk.

Patients with RA suffer greater loss of function and diminished quality of life than patients with osteoarthritis. One study ranks RA as #19 for the most common cause of work years lost to disability, a finding considered particularly remarkable due to the rarity of the condition. The joints are the primary point of disease but other organs can be affected as well, including the lungs, heart, eyes, and skin.

Sources:

1. Arthritis: Rheumatoid Arthritis. CDC / Centers for Disease Control and Prevention. Centers for Disease Control and Prevention. 19 Nov. 2012. Web. 22 Oct. 2014.
2. Handout on Health: Rheumatoid Arthritis. NIH / National Institute of Arthritis and Musculoskeletal and Skin Diseases. National Institutes of Health. Aug. 2014. Web. 22 Oct. 2014.