What are Patient Reported Outcomes (PROs)?
Patient-reported outcomes refers to information that comes directly from the patient. In the past, most of the main information used when diagnosing and monitoring patients and assessing response to treatments came from the doctor’s evaluation along with the results of blood tests and imaging (x-ray). However, some PROs have been in use for many years. For example, most people with rheumatoid arthritis (RA) are used to their doctors asking them about their pain, ability to do everyday activities, and impression about how well their disease is being controlled at each visit.
PRO information usually is obtained from a paper and pencil test or an interview with the patient during a clinic or research study visit. Today, technology such as computers (including tablets such as the iPad) and even “smartphones” can be used to collect PROs between study and clinic visits. This helps doctors learn more about how their patients are doing between visits.
Why is there so much interest in PROs and patient centered outcomes recently?
People who live with a rheumatic condition recognize it is common to have good and bad days, and even periods of time when their disease worsens or flares. Doctors and researchers need to understand the full range of day-to-day experiences of people who live with a chronic medical condition. For example, in 2002, fatigue was identified as an important symptom by patients attending the international OMERACT (Outcome Measures in Rheumatology: http://www.omeract.org/ ) meeting of rheumatology professionals. Further work showed that many considered fatigue to be one of their most debilitating and problematic symptoms.* Soon it became clear that by asking directly about fatigue, rheumatologists could have a better understanding of how their patient’s RA was affecting them at work, home and every day life. Now, OMERACT recommends that information about fatigue be routinely collected as part of the core set of RA outcome measures.**
PROs also offer an important new way to help evaluate how well people respond to treatment. The revolutionary treatments developed for for rheumatic diseases over the past 15 years can greatly reduce symptoms and even put many in remission (a point where symptoms are no longer evident). Generally, in most trials that study medications and other complementary treatments (e.g., exercise, accupuncture), when traditional disease activity measures (e.g., CRP, swollen joint counts) improve, people also report their pain, fatigue and physical function also improves significantly. Combining information from traditional disease measures with PROs allows patients and their doctors to make more informed decisions to manage the disease and identify the treatments that work best for each individual.
How else are PROs often used?
In RA and psoriatic arthritis, some PROs are included in composite scores that try to carefully measure how active a person’s disease is, and their response to treatment. Examples of disease measurement scores used in RA include the Disease Activity Score (DAS), the Clinical Disease Activity Index (CDAI), and the Simplified Disease Activity Index (SDAI). In other conditions such as ankylosing spondylitis, PROs are also used and include the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and Bath Ankylosing Spondylitis Functional Index (BASFI). Common indicators used to determine if people are responding to treatment include American College of Rheumatology Responder Criteria (such as the ACR20).
Is more work really needed on PROs in rheumatic diseases?
One problem with current PROs is that they may not ask about symptoms that bother patients the most. For example, many people with rheumatic conditions report that they have a lot of stiffness in their joints or throughout their body. Sometimes the stiffness is limited to the morning, but for others, it may appear only in the afternoon or linger through the day. To date, doctors and researchers have not agreed upon the best way to ask about stiffness or measure its severity. In order to understand the impact of stiffness in the lives of patients, as well as how effective current treatments are, a new PRO for stiffness is needed. Stiffness is just one example, there needs to be more PROs to measure the range of symptoms that matter most to patients.
However, PRO development is not a fast or easy process. To ensure that PROs are relevant, reliable and valid, they must undergo a rigorous process of development and testing. First, persons living with the disease must describe the symptoms that bother them the most. After a PRO measure is developed, it must show that it in fact measures what it is supposed to measure. Finally, it must be tested in a large number of people living with the disease to be sure it can detect changes over time (getting better and getting worse), and in response to different treatments. This is a long process can take several years, but is very important in developing useful PROs that can be used to improve the lives of people living with rheumatic diseases.
*Hewlett S et al., Patients’ perceptions of fatigue in rheumatoid arthritis: overwhelming, uncontrollable, ignored. Arth Rheum 2005;53:697-702. **Kirwan JR et al., Patient perspective: fatigue as a recommended patient centered outcome measure in rheumatoid arthritis. J Rheumatol 2007;34:1174-7.