Background/Purpose: Relapsing polychondritis (RP) is a rare chronic disabling inflammatory condition primarily affecting cartilage tissue. Self-reported patient outcome measures, which have not been evaluated in RP, are necessary to understand how RP disease manifestations affects patients. The objective of this study was to compare patient and physician assessment of disease activity in a cohort of patients with RP to determine the need for multimodal response criteria in RP.

Methods: Adult patients who fulfilled diagnostic criteria for RP were recruited into a prospective, observational cohort. Patients underwent a standardized comprehensive evaluation at six-month interval visits that included a clinical evaluation by rheumatology and otolaryngology, laboratory studies, audiology, and chest imaging. From this information, physicians rated the Physician Global Assessment (PhGA) on a scale of 0 to 10. Patients simultaneously completed four patient-reported outcome questionnaires: Patient Global Assessment (PtGA), SF-36 Health Survey, Brief Illness Perception Questionnaire (BIPQ), and Multidimensional Fatigue Inventory (MFI). The intraclass correlation coefficient (ICC) (2, 1) was calculated to determine the agreement between physicians and patients. Patient – Physician discordance was defined as a difference (PtGA-PhGA). Visit characteristics were compared between the positive discordant group and the concordant group using Mann Whitney or Fisher’s exact test.  Response to treatment was analyzed in all patients who had at least two study visits. 

Results: A total of 154 visits from 76 patients were analyzed. The median PhGA was 3 (interquartile range 2-3) and median PtGA was 5 (interquartile range 4-7). The ICC was low (0.14; 95% confidence interval -0.06 to 0.334, p=0.10). PtGA and PhGA were concordant in 66 visits (42.6%). In a total of 84 visits (54.2%), patients scored disease activity 3 or more points higher than physicians (positive discordance), whereas in only 4 visits (2.6%) PtGA was 3 or more points less than PhGA (negative discordance). Compared to visits with concordance, visits with positive discordance were associated significantly with worse scores on the MFI, BIPQ, SF 36 Physical component score (PCS), and SF 25 Mental component score (MCS). There were no differences in demographics, medication use, clinical symptoms, or objective measures of airway inflammation between the concordant and positively discordant groups. Treatment was increased over 52 visit intervals in 36 patients. Whereas PhGA scores significantly improved in response to increased treatment from a median 3 (interquartile range 2-4) to 2 (interquartile range 2-3) (P< 0.01), there was no significant change in PtGA.  (Figure 1)

Conclusion: Patients with RP typically self-report higher disease activity than their physician counterparts and do not necessarily perceive similar improvement in response to treatment.  Discordance is possibly due to the psychological burden of illness experienced by patients. Future disease activity assessment instruments in RP should consider the utilization of composite response criteria that incorporate patient-reported outcome measures.

Figure 1. Increased treatment improves disease activity from physician (median change PhGA=-1 , IQR= -2-0) but not patient perspective (median change PtGA=0 , IQR= -1-1)

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ACR Meeting Abstracts - https://acrabstracts.org/abstract/discordance-in-patient-and-physician-assessment-of-disease-activity-in-relapsing-polychondritis/