The 2010 American College of Rheumatology/European League Against Rheumatism Classification Criteria for RA Criteria 14 Use of oral contraceptive pills or vitamin E does not affect RA risk. 13, 14 Breastfeeding decreases the risk of RA (RR = 0.5 in women who breastfeed for at least 24 months), whereas early menarche (RR = 1.3 for those with menarche at 10 years of age or younger) and very irregular menstrual periods (RR = 1.5) increase risk. 12 Parity may have long-lasting impact RA is less likely to be diagnosed in parous women than in nulliparous women (RR = 0.61). Pregnancy often causes RA remission, likely because of immunologic tolerance. 1 Both current and prior cigarette smoking increases the risk of RA (relative risk = 1.4, up to 2.2 for more than 40-pack-year smokers). Older age, a family history of the disease, and female sex are associated with increased risk of RA, although the sex differential is less prominent in older patients. Overproduction of proinflammatory cytokines, including tumor necrosis factor (TNF) and interleukin-6, drives the destructive process. Subsequent pannus formation may lead to underlying cartilage destruction and bony erosions. RA is characterized by inflammatory pathways that lead to proliferation of synovial cells in joints. 8 Although infections may unmask an autoimmune response, no particular pathogen has been proven to cause RA. 5 Smoking is the major environmental trigger for RA, especially in those with a genetic predisposition. 6, 7 Genome-wide association studies have identified additional genetic signatures that increase the risk of RA and other autoimmune diseases, including STAT4 gene and CD40 locus. 4 Genetic associations for RA include human leukocyte antigen-DR4 5 and -DRB1, and a variety of alleles called the shared epitope. Genetic susceptibility is evident in familial clustering and monozygotic twin studies, with 50 percent of RA risk attributable to genetic factors. Like many autoimmune diseases, the etiology of RA is multifactorial. cohort, 35 percent of patients with RA had work disability after 10 years. 1 Onset can occur at any age, but peaks between 30 and 50 years. Rheumatoid arthritis (RA) is the most common inflammatory arthritis, with a lifetime prevalence of up to 1 percent worldwide. Joint replacement is indicated for patients with severe joint damage whose symptoms are poorly controlled by medical management. The goals of treatment include minimization of joint pain and swelling, prevention of radiographic damage and visible deformity, and continuation of work and personal activities. Biologic agents, such as tumor necrosis factor inhibitors, are generally considered second-line agents or can be added for dual therapy. Methotrexate is typically the first-line drug for rheumatoid arthritis. Combinations of medications are often used to control the disease. Earlier diagnosis of rheumatoid arthritis allows for earlier treatment with disease-modifying antirheumatic agents.
Patients taking biologic agents should be tested for hepatitis B, hepatitis C, and tuberculosis. Initial laboratory evaluation should also include complete blood count with differential and assessment of renal and hepatic function. In a patient with inflammatory arthritis, the presence of a rheumatoid factor or anti-citrullinated protein antibody, or elevated C-reactive protein level or erythrocyte sedimentation rate suggests a diagnosis of rheumatoid arthritis. The likelihood of a rheumatoid arthritis diagnosis increases with the number of small joints involved. Criteria for diagnosis include having at least one joint with definite swelling that is not explained by another disease.
Women, smokers, and those with a family history of the disease are most often affected. Rheumatoid arthritis is the most commonly diagnosed systemic inflammatory arthritis.