Rheumatoid arthritis (RA) is an autoimmune disease that causes inflammation and progressive damage to the joints. It typically starts in smaller joints like the hands and feet before spreading to larger joints like the knees, hips, shoulders and elbows. The speed at which RA spreads from joint to joint can vary significantly between patients.
What is rheumatoid arthritis?
Rheumatoid arthritis is an autoimmune disorder, meaning the immune system mistakenly attacks healthy tissue. In RA, the immune system attacks the lining of the joints, called the synovium. This causes swelling, pain and joint damage over time.
RA is a systemic disease, meaning it can affect the whole body. While joints are the primary target, inflammation can occur in other tissues like the lungs, heart and eyes.
Around 1.3 million Americans have rheumatoid arthritis. It affects women 2-3 times more often than men. Rheumatoid arthritis most commonly begins between the ages of 30-60.
How does rheumatoid arthritis spread between joints?
The underlying mechanism that causes RA to move from joint to joint is not fully understood. Researchers believe several factors likely play a role:
- Inflammation – Chemicals released by the overactive immune system cause inflammation. This can spread from the original affected joint to nearby joints.
- Genetics – Certain genes are associated with more rapidly progressive joint damage in RA.
- Environmental triggers – Things like infections, hormones or trauma to a joint might trigger inflammation in additional joints.
- Age – Younger people generally have more aggressive disease spread.
Common pattern of joint involvement
While joint inflammation can occur almost anywhere in the body, RA tends to follow a typical pattern of progressively involving new joints over time:
- Small joints – The wrists, fingers, toes, ankles and elbows are usually affected first.
- Large joints – The shoulders, knees, hips, jaw and neck are often affected after smaller joints.
- Axial skeleton – Inflammation of the spine, pelvis and chest can occur later in the disease.
This pattern relates to differences between small and large joints:
- Smaller joints have a higher ratio of synovium to joint space. More synovium means more potential area for inflammation.
- Larger joints have more cartilage and fluid cushioning them. More cushioning means it takes longer for inflammation to cause bone and cartilage damage.
Speed of rheumatoid arthritis progression
There is no set timeline for how quickly rheumatoid arthritis spreads from joint to joint. Factors influencing the speed of progression include:
Disease severity
Patients with more severe RA tend to have faster spreading of joint inflammation. Disease severity is measured by:
- Number of tender and swollen joints
- Presence of rheumatoid nodules
- Amount of inflammation measured in blood tests
Genetic markers
Variations in certain genes linked to immune system function can accelerate the progression of RA. For example, one genetic marker called HLA-DRB1 is tied to more rapid joint damage.
Age of onset
Younger people who develop RA tend to have more aggressive progression than those diagnosed later in life. The reasons for this aren’t entirely clear.
Delay in treatment
Beginning treatment quickly after diagnosis, especially with DMARD medications that slow disease progression, helps limit the spread of RA inflammation to additional joints.
Poor medication adherence
Patients who don’t take RA medications regularly as prescribed experience faster progression of joint damage. Staying on medications consistently can significantly slow the spread of RA.
Ongoing inflammation
Higher baseline inflammation and frequent inflammatory flares also accelerate the involvement of new joints. Keeping inflammation well-controlled limits progression.
Stages of rheumatoid arthritis progression
Doctors often break down the course of rheumatoid arthritis into 3 general stages:
Early RA
- Joint symptoms present for less than 6 months
- Inflammation and damage usually confined to smaller joints
- Presence of autoantibodies like rheumatoid factor common
- Visible joint damage on x-rays less common
Established RA
- Joint symptoms for 6 months to several years
- Ongoing inflammation leading to tendon and ligament damage
- Inflammation spreading to larger joints and axial skeleton
- Joint damage visible on x-rays becomes more apparent
Late RA
- Joint symptoms for many years
- Severe joint destruction visible on x-rays
- Decreased inflammation but increased physical disability
- Higher incidence of extraskeletal manifestations (heart, lung)
However, there is high variability in the pattern and speed of joint involvement between patients. Some rapidly progress through these stages, while others remain in an early stage indefinitely.
Factors affecting progression of rheumatoid arthritis
Many variables influence both the pattern of joints affected and the speed at which additional joints become involved:
Medications
Early, aggressive treatment with DMARDs and biologics that halt inflammation and joint damage dramatically slows progression. Corticosteroids also temporarily limit inflammation.
Supportive treatments
Braces, splints, orthotics and physical therapy support vulnerable joints and help limit deformities. Assistive devices reduce mechanical stress on damaged joints.
Smoking
Smoking worsens the progression and severity of rheumatoid arthritis joint damage. Quitting can significantly slow progression.
Pregnancy
The hormonal changes of pregnancy often lead to improvement in RA inflammation and symptoms during the 2nd and 3rd trimesters. After birth, RA activity frequently flares up again.
Infections
Bacterial and viral infections can trigger immune system activity that exacerbates RA inflammation and causes flare-ups.
Emotional health
Stress, anxiety and depression negatively impact RA disease activity and pain levels. Improving coping skills and emotional health aids in disease management.
Weight management
Excess weight puts additional mechanical stress on weight-bearing joints. Losing weight reduces strain on damaged joints.
| Factor | Effect on RA Progression |
|---|---|
| Medications (DMARDs, biologics) | Slows progression |
| Supportive treatments (braces, PT) | Slows progression |
| Smoking | Accelerates progression |
| Pregnancy | Temporary improvement |
| Infections | Triggers flares, accelerates progression |
| Emotional health | Stress exacerbates symptoms |
| Weight management | Excess weight accelerates damage |
Monitoring spread of rheumatoid arthritis
Doctors use several methods to monitor the progression of rheumatoid arthritis over time:
Physical exams
Counting the number of tender/swollen joints helps assess the extent of RA involvement. This is used to calculate disease activity scores.
Lab tests
Inflammatory markers in the blood like erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) help gauge systemic inflammation.
Imaging
X-rays, ultrasound and MRI scans assess joint damage and inflammation. Repeat imaging shows disease progression.
Questionnaires
Patient questionnaires evaluate physical functioning, pain levels, fatigue, and quality of life. Worsening scores may reflect spreading joint damage.
Slowing the spread of rheumatoid arthritis
While there is no cure for rheumatoid arthritis, early treatment and lifestyle habits can have a huge impact on limiting the speed and extent of joint damage over time. Key strategies include:
- Beginning DMARD drug therapy quickly after diagnosis rather than waiting for damage to occur.
- Using biologic drugs in patients with aggressive disease progression.
- Monitoring disease activity frequently and adjusting medications to reach remission.
- Quitting smoking and maintaining emotional health.
- Using joint protection techniques to avoid overuse of damaged joints.
- Engaging in regular exercise to preserve joint mobility.
Conclusion
The progression of rheumatoid arthritis from joint to joint is highly variable between patients. Young age at onset, high disease severity, genetic factors, smoking and delayed treatment accelerate the spread to new joints. Early diagnosis, aggressive treatment, and healthy lifestyle habits are key to limiting progression.