Tests That Track Rheumatoid Arthritis Progression
Medically reviewed by Anita C. Chandrasekaran, MD, MPH
Rheumatoid arthritis (RA) is a type of inflammatory arthritis that causes joint pain, stiffness, and swelling. It is marked by periods of worsening symptoms, known as flare-ups. Some people with RA also have problems with other parts of their body, including their eyes, lungs, and skin, and more general symptoms, such as fatigue and fever.
RA is also an autoimmune disease—a condition in which the immune system, which usually fights off invading substances like bacteria, viruses, and toxins, starts to attack its own healthy tissues. With RA, those attacks are focused on the linings of the joints, called the synovium. Over time, these inflammatory attacks can damage the joints, cartilage, and bone.
Your rheumatologist (a specialist in arthritis and other diseases of the bones, muscles, and joints) will want to regularly assess RA disease activity to determine whether treatments are working or if the disease is worsening. This article will cover the importance of measuring disease progression, how it is measured, the stages of RA progression, signs of RA getting worse, and more.
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Why Is Measuring the Progression of RA Important?
The main feature of RA is persistent joint inflammation that affects joints on both sides of the body equally (symmetrically). The severity of RA will change over time. For people with untreated or undertreated RA, it is a progressive condition that eventually leads to some degree of joint destruction and a significant decline in function.
People with RA might report struggles with performing activities of daily living, such as walking, standing, getting dressed, caring for themselves, and any activity that involves the use of the hands.
Fortunately, the last few decades have seen drastic improvements in the treatment of RA, with disease remission becoming a reality for many. To reach these goals, healthcare providers need to measure disease activity. Research shows monitoring the condition is the best way to improve treatment outcomes.
There are different methods for this, including disease activity scoring and the Vectra blood test.
What Is RA Remission?
RA remission is either the total absence of symptoms or low disease activity. In remission, symptoms are controlled, quality of life is improved, and damaging inflammation has stopped. Remission can last from several months to several years before the condition relapses and symptoms and inflammation return.
Related: Benefits of Tracking Your RA Disease Progression
What Is a Disease Activity Score (DAS)?
The disease activity score (DAS) was developed to allow healthcare providers a quantitative index (one based on numbers) to measure, study, and manage RA disease activity in everyday clinical practice and for researchers to use in long-term observational studies.
DAS also acts as a continuous method for measuring RA disease activity by looking at the number of swollen and tender joints, lab reports, and patient self-reports.
The American College of Rheumatology recommends DAS28 as one of the most reliable methods for measuring disease activity in RA. DAS28 evaluates 28 joints and does not include the ankles or the joints in the feet.
Your healthcare provider can determine your DAS28 score relying on:
The number of swollen joints out of 28
The number of tender joints out of 28
C-reactive protein (CRP) or erythrocyte sedimentation rate (ESR) blood work: CRP and ESR tests indicate how much inflammation is in your body. Both increase with active inflammation, but CRP rises and resolves faster. ESR will take longer to rise, but it will stay high even after inflammation has resolved.
Patient health assessment questionnaires
A mathematical formula is then used to calculate the overall DAS28 score, ranging from 0 to 9.4. The score ranges in the DAS28 scoring system are:
High disease activity: 5.1 or higher
Moderate disease activity: 3.2 to 5.1
Low disease activity: 2.6 to 3.2
Remission: 2.6 or lower
DAS scoring helps your healthcare provider determine whether your treatment plan is working. With this information, they can make changes to your treatment plan, remove or add treatments, and better understand what may or may not help you feel better and keep RA inflammation at bay.
In addition to DAS28, the American College of Rheumatology has recommended additional methods for measuring disease activity in clinical care. These are the Clinical Disease Activity Index (CDAI), the Simplified Disease Activity Index (SDAI), the Routine Assessment of Patient Index Data 3 (RAPID3), and the Patient Activity Scale-II (PAS-II).
DAS28 is the most common test, but all of these methods can be applied to individual patients or clinical practices.
The Vectra DA Blood Test
The Vectra DA blood test is a newer blood test that measures disease activity in people who have RA.
Your healthcare provider might order the Vectra DA test if you take disease-modifying antirheumatic drugs (DMARDs) or biologic drugs and do not see improvement. They might also consider this test to assess the potential for future joint damage or determine if changes to your treatment plan are necessary.
The Vectra DA test might be able to predict flare activity and sustained remission in people who discontinue treatment. It is considered a reliable tool for predicting patient response to biologic and non-biologic treatments.
The Vectra DA measures 12 different biomarkers (molecules in the blood that can be objectively quantified) linked to RA disease activity. The results of the Vectra DA test range from 0 to 100, in which 1–29 indicates low disease activity, 30–44 is moderate disease activity, and 45–100 is high disease activity.
With Vectra DA scoring information, your rheumatologist can make better decisions about your treatment plan. This scoring is helpful because people with high levels of disease in RA are at an increased risk for joint and bone damage compared to people with low or moderate disease activity scores.
Doctors do not always use the Vectra DA test due to its high cost. It is also possible your insurance may not cover it. If your rheumatologist deems this test necessary, their staff will reach out to you regarding financial assistance that the manufacturer might provide. If no options are available to help pay for Vectra DA, your doctor will utilize other methods for tracking RA disease activity and progression.
Other Tests
In addition to DAS28 and Vectra, your rheumatologist may use other testing methods to measure RA disease activity and progression, including imaging and blood work that check inflammation levels.
Imaging
X-ray imaging has been a vital tool for monitoring RA disease progression and joint damage for decades. And now with more modern imaging methods, including ultrasound and magnetic resonance imaging (MRI), it is possible to pinpoint early signs of joint damage in RA that cannot be seen in X-rays.
For example, both MRI and ultrasound are more sensitive at detecting bone erosion and they can reveal inflammation, including synovitis (inflammation of the lining of the joints).
Both MRI and ultrasound are much more expensive than x-rays. Therefore, your rheumatologist will use these methods as infrequently as possible and only as necessary.
Blood Work
People with RA often have elevated erythrocyte sedimentation rate (ESR or sed rate) or C-reactive protein (CRP) levels. These tests indicate the presence of inflammation in the body.
An ESR blood test looks at how fast red blood cells reach the bottom of a test tube. The faster they fall, the more severe inflammation is. They fall fast because inflammation will cause blood proteins to clump and become heavier.
CRP is a protein made by the liver and is sent into the bloodstream to respond to inflammation. Much like the ESR test, the CRP test measures inflammation in the body. Neither test can explain the cause or location of the inflammation.
But knowing how much inflammation you have in your body and how frequently it occurs might be a way to monitor disease progression and high disease activity, or whether medications are helping. With this information, your doctor can adjust your treatment plan to reduce inflammation, pain, and other disease symptoms.
ESR and CRP labs are not specific tools for measuring or confirming disease progression. However, they are useful along with other testing methods, including imaging and disease activity scoring. Other abnormalities can be seen in blood work with chronic inflammation, including an elevated white blood cell count, elevated platelet count, anemia, and low serum albumin.
Stages of Rheumatoid Arthritis
RA is a condition that tends to worsen over time, progressing through specific stages. There is no exact timeline for disease progression. With newer, more potent treatments, progression timetables have drastically changed over the past few decades.
RA will progress in stages. The stages of RA are:
Early-stage, or stage 1: At this stage, you feel joint pain, stiffness, and swelling because the lining of the joints is inflamed. There is no joint or bone damage at this early stage.
Moderate-stage, or stage 2: In this stage, inflammation of the synovium starts to damage cartilage—the tissue that covers the bone where it meets the joints. It acts as a protective cushion between bones and joints. Cartilage damage can cause pain, loss of mobility, and reduced range of motion in affected joints.
Severe-stage, or stage 3: At this stage, RA becomes severe, and damage affects cartilage and bone. With the cushion worn away, the bone starts to rub against bone, leading to bone-on-bone pain. Bones and joints can become damaged, deformity might occur, and some people may experience muscle weakness and loss of mobility.
End-stage, or stage 4: At this stage, joints no longer work because they are damaged and deformed. There might be severe pain, swelling, and loss of mobility.
RA progression through all four stages can take years or decades. Some people may never reach the later stages of RA progression. It is possible to remain in any of the stages for a long time. It is also possible to experience remission for an extended period.
Signs Your RA Is Progressing
You will need to work with a rheumatologist to determine if your RA is improving or getting worse. While RA is an unpredictable condition, you can still monitor symptoms and be on the lookout for signs of progression.
Signs of RA progression might include:
More frequent disease flares
More intense and long-lasting flares
New pain and swelling in joints not previously affected
Daily activities become harder
Loss of mobility due to pain, stiffness, fatigue, and other RA symptoms
Rheumatoid nodules (lumps under the skin, usually around the elbows)
Active inflammation that frequently shows up in blood work
Evidence of joint or bone damage on X-rays and other imaging
Marked decreases in mobility and muscle strength
Rheumatoid Arthritis Prognosis
Early on, RA prognosis (likely outcome) is based on how advanced the disease might be at diagnosis. Your healthcare provider will also want to understand how active your disease is. They will consider high disease activity scores, the early presence of joint damage, and rheumatoid factor (RF) or anti-citrullinated protein-peptide antibodies (ACPA).
What Are RF and ACPA Testing?
The RF test measures RF markers in the blood that are a sign of RA or another autoimmune disease. ACPA testing looks for autoantibodies commonly observed in the blood of people with RA.
Additional factors considered in prognosis might include:
The level of functional disability
Extra-articular disease: Involvement of systems other than the joints, most commonly eyes, lungs, and skin
Severity of other symptoms such as fatigue, malaise (general feeling of being unwell), fever, and weakness
Results of imaging studies
Specific biomarkers linked to RA
RA isn't considered a fatal condition. However, studies have shown a higher mortality rate for people with rheumatoid arthritis compared to the general population.
The most common cause of death in people with RA is cardiovascular, as chronic inflammation accelerates plaque formation in blood vessels. Prognosis is even worse in patients with lung involvement. However, aggressive, early treatment can reduce/eliminate these risks.
Thanks to improved treatment options and awareness of disease complications, RA life expectancy has improved over the past few decades, and people with RA are living longer and healthier lives.
Summary
Rheumatoid arthritis is a lifelong condition that will worsen and progress over time. Disease progression could mean severe joint damage or disease complications.
Your healthcare provider will employ different techniques to measure disease activity and determine treatment goals to avoid severe disease outcomes. Doing so might improve your prognosis and help you live longer and healthier despite RA.
A Word From Verywell
RA is a lifelong condition without a cure. Fortunately, there are ways to decrease pain and inflammation and slow down disease progression. Early diagnosis and effective treatment are vital because any damage that affects the joints and bones is permanent.
Make sure you see a rheumatologist or a healthcare provider familiar with RA. Follow your treatment plan. It is also wise to make healthy lifestyle choices, including eating a healthy and balanced diet, staying active, managing stress, and not smoking.
Frequently Asked Questions
How do you measure the severity of rheumatoid arthritis?
Different testing methods can measure disease activity and severity in rheumatoid arthritis, including imaging, blood work, and patient self-assessments.
How quickly does rheumatoid arthritis progress?
Rheumatoid arthritis will worsen over time, but there is no exact timeline for disease progression. Some people with RA will have a mild disease for most of their lives, while others experience a more severe disease course leading to joint damage and disease complications over time.
What does the Vectra test measure?
The Vectra test measures 12 biomarkers present in the blood of people with RA. These biomarkers are linked to RA disease activity.
Read the original article on Verywell Health.
