Can tender and swollen joint counts work in a telemedicine world? Save
In a world where telemedicine and virtual care are not going away, is there value in patients assessing their own tender and swollen joints?
Work from the Canadian Early Arthritis Cohort (CATCH, @earlyarthritis) presented by Dr. Vivian Bykerk (@BykerkVivian) is the subject of two abstracts from Monday’s poster floor, exploring the utility as to how patient assessments might match up to rheumatologist assessments.
Rheumatologists have long prided themselves on being the arbiter of clinical synovitis, and accurate assessment of this on physical examination usually necessitates expert training over months. With pandemic limitations came a reassessment across medicine of in-person assessment, and increasing attention has returned to how patient joint counts can be used.
Using data from 937 early rheumatoid arthritis patients from the CATCH Cohort, Dr. Bykerk and colleagues assessed changes in joint counts in the three months between assessments (abstract #1203). All patients were asked to rate tender and swollen joints on a 28 joint count using a homunculus, and treating rheumatologists were asked to do the same; these were used to calculate a CDAI. Baseline data for the comparison was taken three months after enrollment in the cohort patients, and all patients had been started on csDMARDs although many remained active, with a mean CDAI of 11.9.
Encouragingly, patient and rheumatologist assessments showed good agreement. While rheumatologists tended to note a slightly higher magnitude of change, consistency between patients and rheumatologists was seen, irrespective of whether they improved, worsened, stayed active, or stayed controlled.
Of course, patient counts do not always match up to rheumatologist assessments, and a natural area of concern is where another source of pain exists: whether that be from widespread pain like fibromyalgia, or regional non-articular pain, such as that from tendinopathies.
In a separate abstract also presented by Dr. Bykerk (abstract #1202) , patients in the CATCH Cohort were asked to fill out a body pain diagram to determine whether they had regional or widespread pain, or no non-articular pain at all, and correlations between patient CDAI and rheumatologist CDAI were observed. Notably, there was similarly good correlation in patients without non-articular pain and in patients with regional pain, suggesting that tendonitis does not need to interfere with the veracity of patient joint counts
In contrast, patients with widespread pain had poorer correlation, although not always in a higher direction. If these patients had active disease, they scored their CDAI on average five points higher than their rheumatologist, but if their disease was controlled, they actually scored their CDAI five points lower on average.
This would suggest that patients with widespread pain, such as those with concomitant fibromyalgia, have difficulty objectively assessing their pain – with those with active RA appreciating an amplified magnitude of pain, and those with controlled RA normalizing it.
These data open up the possibility of harnessing patient joint counts for telemedicine by understanding their best interpretation. If replicable, they would suggest that patient joint counts could help assess the impact of treatment in early rheumatoid arthritis, including in patients with tendonitis, although patients with fibromyalgia might need a different lens of interpretation applied to their results.