Rheumatoid arthritis: causes, symptoms, diagnosis and management

What happens in the body

RA is classified as an autoimmune disease. In affected joints the synovium (the membrane that lines joint capsules) becomes thickened and inflamed, producing excess synovial fluid and enzymes that erode cartilage and bone. A characteristic tissue called pannus—granulation tissue made of inflammatory cells and fibrous tissue—can invade and destroy the articular surface. The resulting loss of cartilage allows bone-on-bone contact, increasing pain and deformity. RA is systemic in many patients and can cause fatigue, low‑grade fever and inflammation in structures beyond the joints, such as the lungs, heart lining, eyes and blood vessels.

Causes and risk factors

The exact trigger for RA is unknown. Current understanding points to an interaction of genetic susceptibility and environmental exposures. Certain gene variants (for example in HLA regions) are linked to higher risk, and smoking is a well established environmental risk factor. Hormonal influences are suspected because RA is more common in women, and some infections may act as initiating events in predisposed people. Autoantibodies, including rheumatoid factor (RF) and anti‑citrullinated peptide antibodies (anti‑CCP), are common and help indicate an autoimmune process, but their presence and levels vary.

Signs, diagnosis and course

Typical symptoms include symmetrical joint pain, morning stiffness lasting more than 30 minutes, swelling and reduced range of motion. Diagnosis is clinical and supported by blood tests, imaging and symptom patterns. Laboratory tests may show elevated inflammatory markers, RF and anti‑CCP antibodies. X‑rays, ultrasound or MRI can reveal joint space narrowing, erosions and synovitis. Early diagnosis and treatment are important because irreversible damage can occur within months to years if inflammation remains uncontrolled.

Treatment and management

Management aims to suppress inflammation, relieve symptoms and preserve function. Core treatments include disease‑modifying antirheumatic drugs (DMARDs) such as methotrexate, and biologic agents that target specific immune pathways. Short‑term corticosteroids and nonsteroidal anti‑inflammatory drugs (NSAIDs) are used for symptom control. Nonpharmacologic care—physical therapy, occupational therapy, patient education, exercise and lifestyle changes like smoking cessation—helps maintain mobility and quality of life. In advanced cases, joint surgery or replacement may be necessary to restore function.

History and notable facts

Descriptions of inflammatory polyarthritis go back centuries, but rheumatoid arthritis was first distinguished as a specific disease in the early 19th century. Since then, classification criteria and treatments have evolved significantly. RA affects women more often than men and most commonly begins in middle adulthood, though it can start at any age. Prognosis varies: many people achieve long periods of low disease activity with modern therapies, while others have more aggressive disease that requires intensive management.

Practical considerations

• Early referral to a specialist improves outcomes.
• Monitoring for medication side effects and comorbidities (cardiovascular risk, infections) is important.
• Self‑management, support groups and rehabilitation services are valuable adjuncts to drug therapy.

Further information and references

For additional reading and authoritative overviews, see these resources:

• Clinical overview
• Autoimmune mechanisms
• Synovial pathology
• Immune system basics
• Inflammation and tissue damage
• Joint involvement in RA
• Extra‑articular manifestations
• Joint capsule anatomy
• Synovitis and swelling
• Synovial fluid role
• Articular cartilage
• Hormonal influences
• Environmental triggers
• Infection hypotheses
• Genetic risk factors