Most rheumatologists have long relied primarily on their own clinical judgment and intuition when deciding whether a patient with rheumatoid arthritis (RA) requires a change in treatment in order to keep the disease under control. However, there is now solid evidence to suggest that RA patients do best when doctors use a so-called “treat to target” approach—that is, adjust a patient’s therapeutic regimen as necessary to achieve a specific goal.

But the treat-to-target philosophy requires information about an RA patient’s “disease activity”—that is whether his or her condition is improving or getting worse. How can you hit your target unless your doctor knows when to increase a dose or add a drug to your regimen? Yet not all rheumatologists in the United States use available tools for monitoring disease activity in RA.

One reason may be that there is no single “gold standard” test for this purpose that’s comparable to, say, a cholesterol test for a heart patient or a blood sugar assay for a diabetes patient. However, last May, the American College of Rheumatology (ACR) recommended six tools for the systematic measurement of disease activity in RA. Using these tools consistently can help identify small changes that a patient may not notice and that may escape a physician’s observation, says rheumatologist Salahuddin Kazi, MD, of the Dallas VA Medical Center, a coauthor of the ACR guidelines. Responding to these changes as soon as possible with a change in drug treatment can help limit the risk for long-term joint damage, says Dr. Kazi.

The sooner a patient gets the right treatment, the less likely he or she will suffer long-term joint damage, Dr. Kazi points out. “It’s like a front-loaded mutual fund,” he says. “You have to make that early investment to see your returns.” Your doctor can’t literally feel your pain, but could he or she help to ease it by using formal tools to track your disease activity?

Many Tools Available

While there may be no acknowledged “best” test for measuring disease activity in RA, dozens of such methods have been devised over the years. Broadly speaking, these tests fall into three categories:

  • Patient questionnaires. A simple version of such a test is the Visual Analog Scale (VAS), which features a horizontal line with the words NO PAIN on the left and WORST PAIN on the right; the patient makes a mark on the line to indicate the point on the spectrum that reflects how he or she is feeling. Other patient-focused tests are more detailed. For example, some ask questions about how much difficulty the patient has performing daily activities, such as bathing, dressing and climbing in and out of cars.
  • Joint counts, in which a doctor examines a specific set of a patient’s joints and tallies the number that are swollen and/or tender. The most common of these tests is the DAS28, which generates a “disease activity score” (hence the acronym “DAS”) based on an examination of 28 joints in the shoulders, arms, hands and knees.
  • Lab tests that measure markers of inflammation. The most widely used measurements are erythrocyte sedimentation rate (ESR), which tracks how fast red blood cells fall in a test tube, and C-reactive protein (CRP), which is manufactured in the liver and rises when inflammation is present.