Rheumatoid Arthritis: Definition, Clinical Features, and Impact
Rheumatoid arthritis is the most common autoimmune disease affecting the joints, characterized by symmetric polyarthritis with joint swelling, prolonged morning stiffness, and potential systemic complications that can significantly reduce life expectancy by 3-5 years. 1
Epidemiology and Risk Factors
- Affects approximately 1% of the global population, with higher prevalence in people of European or Asian ancestry 1
- More common in women than men, with lifetime risk of 3.6% in women versus 1.7% in men in the United States 1
- Typical age of onset is around 55 years, but can develop at any age 1
- Prevalence increases with age, affecting approximately 6% of the white population over 65 years 1
- Recent evidence suggests increasing incidence in women 1
Clinical Presentation
- Characterized by symmetric polyarthritis with joint swelling, primarily affecting hands and feet, though any appendicular joint can be involved 1
- Morning stiffness lasting 1 hour or longer is a cardinal symptom, distinguishing it from osteoarthritis where stiffness typically lasts less than 30 minutes 1, 2
- Extra-articular manifestations include subcutaneous nodules, interstitial lung disease, vasculitis, and inflammatory eye disease, which are markers of severe disease 1
- Presentation patterns may include:
- Insidious onset with symmetric small joint pain and swelling (most common) 3
- Acute or subacute onset (25% of patients) 3
- Palindromic onset (recurrent episodes of oligoarthritis) 3
- Monoarticular presentation 3
- Extra-articular synovitis (tenosynovitis, bursitis) 3
- Polymyalgic-like onset 3
- Systemic symptoms (malaise, fatigue, weight loss, fever) 3
Diagnostic Criteria
- Diagnosis is based on confirmed synovitis in at least one joint, absence of alternative diagnoses, and a score of 6 or higher across four domains 1:
- Number and site of involved joints (score 0-5)
- Serologic abnormality (score 0-3)
- Increased acute-phase response (score 0-1)
- Symptom duration (score 0-1)
- Laboratory testing includes:
- Urgent specialist referral is recommended for suspected persistent synovitis, especially when:
Impact on Health and Quality of Life
- Major cause of disability, with more than one-third of patients eventually experiencing work disability 1
- Progressive loss of employment ability: 80% working at 2 years, 68% at 5 years after disease onset 1
- Life expectancy shortened by 3-5 years, particularly in patients with extra-articular manifestations or serious treatment-related adverse effects 1
- Treatment-related complications can include infections, tumors, and gastrointestinal toxicity 1
Pathophysiology
- Multifactorial autoimmune disease with incompletely understood etiology 4, 5
- Characterized by persistent systemic inflammation driven by autoimmune processes 2
- Involves increased production of pro-inflammatory cytokines causing prolonged joint stiffness 2
- Progressive erosion of cartilage and bone due to symmetric inflammation of synovial joints 6
Treatment Goals
- Early diagnosis and prompt treatment are critical to prevent joint destruction and disability 1
- Treatment aims to:
Treatment Options
- Disease-modifying anti-rheumatic drugs (DMARDs) should be initiated within 3 months of diagnosis 6
- Treatment categories include:
- Biologic therapies target specific inflammatory pathways and have dramatically changed treatment outcomes 6
Importance of Early Intervention
- Timely intervention and accurate diagnosis reduce disease burden and progression 1
- Early treatment has led to improved outcomes, with more patients able to work and less need for joint reconstructive surgery 1
- Modern treatment goals include complete abrogation of disease activity and achieving remission or near remission 1