Differences between patient and physician evaluation of disease activity and pain may impact individual treat-to-target strategy
Rheumatoid arthritis and psoriatic arthritis are two types of rheumatic disease. Both are chronic inflammatory diseases that affect a person’s joints, causing pain and disability.
Rheumatoid arthritis can affect men and women of all ages. The inflammation can also affect people’s internal organs. Psoriatic arthritis (sometimes shortened to PsA) gets its name from the link between this type of arthritis and a skin condition called psoriasis, which causes redness and scaling.
Rheumatoid arthritis and psoriatic arthritis can both go into remission. This means that the symptoms of the disease and the underlying inflammation have gone.
WHAT DID THE AUTHORS HOPE TO FIND?
Patients and doctors often disagree about disease activity. The authors wanted to see whether this disagreement could affect whether people can achieve remission in rheumatoid arthritis and psoriatic arthritis.
WHO WAS STUDIED?
The study looked at 2735 people with rheumatoid arthritis and 1236 people with psoriatic arthritis who were starting treatment with disease-modifying antirheumatic drugs (often shortened to DMARDs). These people were treated in clinics across Norway. Everyone included was over the age of 18.
HOW WAS THE STUDY CONDUCTED?
The study was based on people included in a prospective database called NOR-DMARD. Patients in a
registry are not randomised to receive any particular drug, but instead are simply observed and their data recorded.
Assessments of each person were made when they are entered into the registry (baseline), and then after 3, 6 and 12 months and then annually after that. The authors calculated the difference between how many tender (painful) or swollen joints each person had. They also worked out the difference between how severe each person thought their disease was, compared to how severe their doctor thought it was.
WHAT WERE THE MAIN FINDINGS OF THE STUDY?
The study found that the probability of achieving remission decreased in people who had a bigger difference in the number of tender joints compared to swollen joints at the start of treatment. This was true for people with either type of arthritis. People were also less likely to achieve remission if there was a bigger difference between their perception of their disease and their doctor’s.
ARE THESE FINDINGS NEW?
Yes, these findings are new. One previous study found that the likelihood of reaching a 50% improvement
in a treatment response called ACR (American College of Rheumatology criteria) in people with rheumatoid arthritis was lower for people with an elevated swollen-to-tender joint count ratio.
WHAT ARE THE LIMITATIONS OF THE STUDY?
One limitation of the study is that physical examinations were performed by different doctors, which could mean the results are not consistent. Also, the study looked at a lower number of joints than might have been possible, and this might have meant it underestimated the remission rates – particularly in the people with psoriatic arthritis.
WHAT DO THE AUTHORS PLAN ON DOING WITH THIS INFORMATION?
It will be important to communicate the findings of this study to rheumatologists and patients. The results may be important when deciding on treatment targets, as well as when discussing alternative treatments.
WHAT DOES THIS MEAN FOR ME?
These results tell us that it is important to include tender joint count and patient global assessment disease activity in RA as well as in PsA patients. Difficult life events or individual personality characteristics may influence how different people perceive pain, and this needs to be taken into account when evaluating how people should be treated.
If you have rheumatoid arthritis or psoriatic arthritis and have more tender joints than swollen joints, you and your doctor may consider alternative treatment targets or medicines. If you have any concerns about your disease or your treatment, you should talk to your doctor.
Disclaimer: This is a summary of a scientific article written by a medical professional (“the Original Article”). The Summary is written to assist non medically trained readers to understand general points of the Original Article. It is supplied “as is” without any warranty. You should note that the Original Article (and Summary) may not be fully relevant nor accurate as medical science is constantly changing and errors can occur. It is therefore very important that readers not rely on the content in the Summary and consult their medical professionals for all aspects of their health care and only rely on the Summary if directed to do so by their medical professional.
Please view our full Website Terms and Conditions.
Date prepared: April 2017
Summary based on research article published on: 4 October 2016
From: Michelsen, B. et al. Discordance between tender and swollen joint count as well as patient’s and evaluator’s global assessment may reduce likelihood of remission in patients with rheumatoid arthritis and psoriatic arthritis: data from the prospective multicentre NOR-DMARD study. Ann Rheum Dis 2017;76:708–711. doi:10.1136/annrheumdis-2016-210283.
Copyright © 2017 BMJ Publishing Group Ltd & European League Against Rheumatism. Medical professionals may print copies for their and their patients and students non commercial use. Other individuals may print a single copy for their personal, non commercial use. For other uses please contact our Rights and Licensing Team.