Rheumatoid arthritis is a chronic, symmetric autoimmune polyarthritis in which the body's own immune system targets the synovial lining of joints, producing persistent inflammation, cartilage erosion, and progressive bone damage. It affects roughly 0.5-1% of adults worldwide — about 18 million people in the GBD 2019 estimate — with women diagnosed 2-3 times more often than men and peak onset between ages 40 and 60.
Rheumatoid arthritis (ICD-10: M05 seropositive, M06 seronegative) is a systemic autoimmune disease defined by chronic inflammatory synovitis that, left untreated, erodes cartilage and bone and produces irreversible joint deformity. The disease begins with breakdown of immune tolerance to citrullinated self-proteins; autoantibodies such as rheumatoid factor (RF) and anti-cyclic citrullinated peptide (anti-CCP) antibodies appear in serum years before joint symptoms in many patients. Activated synovial fibroblasts, macrophages, and T and B lymphocytes drive a self-sustaining inflammatory loop dominated by tumor necrosis factor (TNF), interleukin-6 (IL-6), and JAK-STAT signaling. The synovium thickens into a pannus that invades cartilage and subchondral bone, producing the characteristic radiographic erosions.
The key symptoms of Rheumatoid Arthritis are: Morning stiffness lasting more than 60 minutes that eases with activity through the day — a hallmark distinguishing RA from mechanical joint pain., Symmetric pain, swelling, and tenderness in the small joints of both hands and feet, particularly the metacarpophalangeal (MCP), proximal interphalangeal (PIP), and metatarsophalangeal (MTP) joints, with the distal interphalangeal (DIP) joints characteristically spared., Boggy soft-tissue swelling and warmth over involved joints, distinct from the bony enlargement of osteoarthritis., Persistent fatigue out of proportion to activity, often present months before joint pain becomes evident, and a leading patient-reported symptom in surveys., Low-grade fevers, weight loss, and malaise during active flares, reflecting the systemic inflammatory nature of the disease., Wrist pain and swelling with reduced grip strength — wrist involvement is present in over 75% of patients within the first two years., Foot pain on first weight-bearing in the morning from MTP synovitis; many patients describe walking on pebbles..
Diagnosis of rheumatoid arthritis combines a careful history of inflammatory joint pain, a tender and swollen joint count on examination, serology, acute-phase reactants, and increasingly imaging. The 2010 ACR/EULAR classification criteria (Aletaha 2010) score four domains — joint involvement, serology (RF and anti-CCP), acute-phase reactants (ESR or CRP), and symptom duration of at least six weeks — with a total of six or more out of ten points classifying the patient as having definite RA. The criteria deliberately favor early detection so disease-modifying therapy can start within the so-called window of opportunity in the first three to six months. Rheumatoid factor is positive in roughly 70-80% of patients but is not specific — it occurs in healthy elderly people, hepatitis C, and other autoimmune diseases. Anti-CCP antibodies are present in roughly 70% of patients and carry around 95% specificity, making a positive anti-CCP highly suggestive of RA and an indicator of erosive disease. ESR and CRP are elevated in active disease and used both for diagnosis and for monitoring. Plain radiographs of hands and feet establish baseline and detect periarticular osteopenia or early erosions; magnetic resonance imaging and high-resolution musculoskeletal ultrasound are more sensitive and can show subclinical synovitis and bone marrow edema before erosions appear on X-ray. Synovial fluid analysis is used selectively to exclude crystal arthritis or septic arthritis. The decisive step in practice is referral to a rheumatologist within six weeks of persistent inflammatory joint symptoms — earlier referral and treatment correlates strongly with sustained remission.
With early diagnosis and modern treat-to-target therapy, the majority of patients now achieve low disease activity or remission, and structural damage is far less common than in pre-biologic decades. Sustained remission rates approach 40-60% in registry data within the first 1-2 years of treatment, and most patients maintain work and daily function. Despite this, RA still carries roughly 50% increased cardiovascular mortality through accelerated atherosclerosis and doubles the risk of lymphoma; aggressive disease control, smoking cessation, and cardiovascular risk management partially offset this excess. Key predictors of worse prognosis include seropositivity for both RF and anti-CCP, early erosions on imaging, high baseline disease activity, smoking, female sex, and lower socioeconomic status. The strongest predictor of a favorable long-term outcome is DMARD initiation within the first three to six months of symptom onset, underscoring the value of urgent specialist referral for new inflammatory joint pain.
A rheumatologist should be seen within six weeks of persistent inflammatory joint symptoms — early DMARD initiation within this window is the single strongest predictor of long-term remission and prevention of joint damage. Specialist input is also required for selecting and rotating biologics or JAK inhibitors, managing pregnancy in RA, evaluating extra-articular complications (interstitial lung disease, scleritis, vasculitis), and coordinating care with cardiology and pulmonology when complications develop.
Find specialists →Methotrexate begins to reduce symptoms over 6-8 weeks, with full response by 3-4 months; biologic DMARDs typically show benefit within 2-12 weeks depending on agent. A treat-to-target visit at three months guides escalation if the target is not met. Sustained remission, once achieved, is reviewed every six months; DMARD tapering may be considered after six to twelve months of sustained remission, though most patients require some maintenance therapy long-term to prevent relapse.
Regular aerobic and resistance exercise is safe and beneficial in RA, including during periods of low disease activity. Aim for 150 minutes per week of moderate aerobic activity combined with twice-weekly resistance work. Hydrotherapy and warm-water exercise are well tolerated when joints are tender. During an acute flare in a single joint, rest and ice that joint while keeping the rest of the body active; complete bed rest worsens fatigue and deconditioning.
Look for board certification in rheumatology, experience with treat-to-target protocols using standardized disease activity scores (DAS28, CDAI, or SDAI), familiarity with biologic and JAK inhibitor selection including the post-ORAL Surveillance safety considerations, in-house musculoskeletal ultrasound capability, and clear care pathways with cardiology, pulmonology, and obstetrics. Continuity matters — RA is a multi-decade relationship, and the same clinician tracking trends in disease activity scores and imaging produces better outcomes than fragmented care.
Medically reviewed by AIHealz Medical Editorial Board · May 12, 2026
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