Session Information
Date: Sunday, October 21, 2018
Title: 3S111 ACR Abstract: Spondyloarthritis Incl PsA–Clinical II: PsA Epidemiology (964–969)
Session Type: ACR Concurrent Abstract Session
Session Time: 4:30PM-6:00PM
Background/Purpose:
Accurate triage methods for patients with psoriasis who have musculoskeletal symptoms could lead to earlier access to rheumatology care for patients with psoriatic arthritis (PsA). We aimed to describe a novel model of care involving a central triage clinic for psoriasis patients with musculoskeletal (MSK) symptoms and to compare the efficacy of several triage methods for PsA.
Methods:
Patients with a physician-confirmed diagnosis of psoriasis who experienced musculoskeletal symptoms and did not have a prior diagnosis of PsA were evaluated. Patients could access the triage clinic by self-referral or following referral by their family physician or dermatologist. Participants were assessed in the central triage clinic to determine their likelihood of having PsA. The following triage methods were used: 1) three PsA screening questionnaires (TOPAS-2, PEST, PASE); 2) MSK ultrasound assessment of 14 pre-specified entheseal sites and 8 joint sites in addition to symptomatic joints and entheses; 3) clinical assessment by an advanced practice physiotherapist; 4) levels of CRP and ESR and 5) The presence of HLA-B*27 allele. Each patient was then assessed by a rheumatologist to determine whether they have PsA. Patients were classified by the rheumatologist to “Not PsA”, “Possible PsA” or “PsA”. The rheumatologist was blinded to the results of the triage methods. The performance of each triage method to identify PsA was assessed by calculating its sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV).
Results:
Of the 203 psoriasis patients assessed in the triage clinic, 137 (67.5%) did not have PsA, 48 (23.5%) had possible PsA, and 18 (9%) had PsA. The performance of triage methods is presented in Table 1. The advanced practice physiotherapist’s assessment in detecting clinical PsA was highly sensitive (89%) with moderate specificity (58%). The screening questionnaires varied by their sensitivity and specificity with PEST showing highest sensitivity (76%) and PASE with highest specificity (79%). The prevalence of positive MSK inflammation by ultrasound (at least 1 joint or enthesis with positive power Doppler signal) was 50.7%. The sensitivity of positive MSK ultrasound was high (83%) but its specificity was moderate (52%). 43.3% of the study participants who had positive MSK ultrasound findings were not classified by the rheumatologist as having PsA. The performance of CRP, ESR and HLA-B27 as triage methods was poor.
Conclusion:
MSK ultrasound and advanced practice physiotherapist were highly sensitive in identifying patients with PsA among psoriasis patients with MSK symptoms. A significant proportion of patients with positive MSK inflammation by ultrasound were not identified as having PsA by the rheumatologist.
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Table 1 – Properties of various triage methods in detecting clinical PsA among patients with psoriasis and musculoskeletal symptoms (N=203) |
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|
Triage Method |
Sensitivity |
Specificity |
PPV |
NPV |
|
Positive MSK ultrasound (Definition 1) at least 1 joint or entheseal sites with positive power Doppler signal |
83% |
52% |
15% |
97% |
|
Positive MSK ultrasound (Definition 2) at least 2 joint or entheseal sites with positive power Doppler signal |
67% |
76% |
21% |
96% |
|
Advanced Practice Physiotherapist: Positive assessment |
89% |
58% |
17% |
98% |
|
Positive TOPAS-2 questionnaire |
72% |
72% |
21% |
96% |
|
Positive PEST questionnaire |
76% |
70% |
15% |
93% |
|
Positive PASE questionnaire |
61% |
79% |
23% |
95% |
|
Elevated CRP (>5 mg/dL) |
44% |
79% |
19% |
94% |
|
Elevated ESR (Men: >15 mm/hr, Women: >20 mm/hr) |
63% |
78% |
21% |
96% |
|
HLA-B*27 allele |
6% |
92% |
7% |
91% |
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MSK – Musculoskeletal, TOPAS – Toronto Psoriatic Arthritis Screening, PEST – Psoriasis Epidemiology Screening Tool, PASE – Psoriatic Arthritis Screening and Evaluation, CRP – C-Reactive Protein, ESR – Erythrocyte Sedimentation Rate |
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To cite this abstract in AMA style:
Eder L, Colaco K, Yeung J, Farrer C, Jerome D. Central Triage Clinic for Psoriatic Arthritis – Performance of Triage Methods [abstract]. Arthritis Rheumatol. 2018; 70 (suppl 9). https://acrabstracts.org/abstract/central-triage-clinic-for-psoriatic-arthritis-performance-of-triage-methods/. Accessed .ACR Meeting Abstracts - https://acrabstracts.org/abstract/central-triage-clinic-for-psoriatic-arthritis-performance-of-triage-methods/