LOOP, a cross-sectional, observational study investigating the clinical specialty setting as a determinant of disease management in psoriatic arthritis: Subgroup analysis results from Japan

PLoS One. 2021 Jan 27;16(1):e0245954. doi: 10.1371/journal.pone.0245954. eCollection 2021.

Abstract

Background: Psoriatic arthritis (PsA) is a progressive erosive joint disorder that causes functional impairment; therefore, early diagnosis and management are essential. This study evaluated the association between clinical specialty and the time to management in patients with PsA in Japan.

Methods: This was a subgroup analysis of a cross-sectional, multicenter, observational study that was conducted in 17 countries outside the United States, including 17 sites at 8 institutions in Japan, from June 2016 to October 2017. Data from consecutive patients (age ≥18 years) with a suspected or established diagnosis of PsA on a routine visit to a participating rheumatology/orthopedic or dermatology clinic in Japan were analyzed. The primary endpoints were time from onset of inflammatory musculoskeletal symptoms to PsA diagnosis, PsA diagnosis to first conventional synthetic disease-modifying antirheumatic drug (csDMARD), PsA diagnosis to first biologic DMARD (bDMARD), and first csDMARD to first bDMARD.

Results: Of 109 patients with a confirmed diagnosis of PsA, 39.4% (n = 43) and 60.6% (n = 66) were recruited by rheumatologists/orthopedists and dermatologists, respectively. Most patients were prescribed tumor necrosis factor inhibitors (58.7%) or methotrexate (56.0%). The mean duration from symptom onset to PsA diagnosis was significantly longer (p = 0.044) for patients treated by rheumatologists/orthopedists (70.6 months) than those treated by dermatologists (30.1 months). In the rheumatology/orthopedic and dermatology settings, the mean time from PsA diagnosis to first csDMARD administration was -0.9 and -2.9 months, and from PsA diagnosis to first bDMARD 21.4 and 14.9 months, respectively. The mean duration from administration of first csDMARD to first bDMARD was comparable in the rheumatology/orthopedic (31.8 months) and dermatology (31.5 months) settings.

Conclusions: Treatment approach was slightly different between rheumatology/orthopedic and dermatology setting in clinical practice in Japan, suggesting that an integrated dermo-rheumatologic approach can optimize the management of patients with PsA.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antirheumatic Agents / administration & dosage
  • Antirheumatic Agents / therapeutic use*
  • Arthritis, Psoriatic / diagnosis*
  • Arthritis, Psoriatic / drug therapy*
  • Arthritis, Psoriatic / epidemiology
  • Cross-Sectional Studies
  • Disease Management
  • Female
  • Humans
  • Japan / epidemiology
  • Male
  • Middle Aged

Substances

  • Antirheumatic Agents

Grants and funding

The funder provided support in the form of salaries for authors SK and FG. The specific roles of these authors are articulated in the ‘author contributions’ section. AbbVie funded the LOOP study, contributed to its design, and participated in collection, analysis, and interpretation of the data and in writing, reviewing, and approval of the publication.