THU0611-HPR MEASUREMENT OF MINIMAL DISEASE ACTIVITY IN PSORIATIC ARTHRITIS USING PROMIS-PHYSICAL FUNCTION OR THE HEALTH ASSESSMENT QUESTIONNAIRE-DISABILITY INDEX

Abstract

Background:Minimal disease activity (MDA) is a treat-to-target strategy (T2T) objective in psoriatic arthritis (PsA). MDA criteria, include physical function, traditionally assessed via the Health-Assessment Questionnaire Disability Index (HAQ-DI). It is of interest to assess the performance of more current physical function instruments such as the Patient-Reported Outcomes Measurement Information System-Physical Function Profile (PROMIS-PF).Objectives:To assess the interchangeability of the HAQ-DI with the PROMIS-PF in the calculation of MDA in PsA.Methods:Longitudinal PsA data were collected including HAQ-DI and PROMIS-PF in a PsA cohort. MDA definitions were built substituting the HAQ-DI criterion with the PROMIS-PF short form 4a (PROMIS-PF4a) or with the PROMIS-PF computer adaptive test (PROMIS-PF Bank). We assessed agreement/accuracy between HAQ-DI based and PROMIS-PF based MDA definitions at each visit and longitudinally through the kappa statistic/ROC curve analysis.Results:One hundred participants contributed 352 observations with up to five visits. Mean (SD) age was 52 (12) years, 60% were female, and 43% were in MDA at baseline. Kappa statistic for PROMIS-PF based MDA reflected almost perfect agreement with HAQ-DI MDA: kappa=0.94 (95% CI 0.90-0.97) for MDA PROMIS-PF Bank, and kappa=0.90 (95% CI 0.80-0.95) for MDA PROMIS-PF4a. Higher longitudinal agreement was seen between MDA HAQ-DI and MDA PROMIS-PF Bank versus MDA PROMIS-PF4a between consecutive visits: kappa ranged between 0.81-0.94 versus 0.72-0.84, respectively (Table 1). Area under ROC curve for predicting MDA HAQ-DI was 0.97 for MDA PROMIS-PF Bank and 0.95 for MDA PROMIS-PF4a (Figure 1).Table 1.Agreement between HAQ-DI based MDA and PROMIS-PF based MDA definitions at each visit and longitudinallyAgreementVisit 1Visit 2Visit 3Visit 4MDA HAQ-DI andMDA PROMIS-PF4aKappa95% CIN0.91(0.80-0.98)860.93(0.82-1.00)810.92(0.80-1.00)720.83(0.66-0.96)58MDA HAQ-DI andMDA PROMIS-PF4aKappa95% CIN0.91(0.81-0.98)860.98(0.90-1.00)820.94(0.84-1.00)730.93(0.82-1.00)58Longitudinal agreementVisit 1 to visit 2Visit 2 to visit 3Visit 3 to visit 4N/AMDA HAQ-DI state change withMDA PROMIS-PF4a state changeKappa95% CIN0.75(0.47-0.95)710.84(0.58-1.00)670.72(0.37-0.94)51N/AMDA HAQ-DI state change with MDA PROMIS-PF Bank state changeKappa95% CIN0.81(0.49-1.00)720.94(0.75-1.00)680.84(0.48-1.00)52N/A*Bias corrected 95% CI were calculated using bootstrapping with 2000 repetitions of individual patients.^MDA state changes are defined as transitions in the respective MDA state between designated consecutive visits.Abbreviations: CI confidence interval; N number of observations; HAQ-DI Heath Assessment Questionnaire-Disability Index; PROMIS-PF4a Patient Reported Outcomes Measurement Information System Physical Function form 4a; PROMIS-PF Bank Patient Reported Outcomes Measurement Information System Physical Function Bank administered as a computer adaptive test; MDA HAQ-DI Minimal disease activity includes the HAQ-DI ≤0.5 criterion; MDA PROMIS-PF4a includes the PROMIS-PF4a ≥41.3 criterion; MDA PROMIS-PF Bank includes the PROMIS-PF CAT ≥41.3 criterion.Figure 1.Areas under receiver operative characteristic curve to predict HAQ-DI based MDA using MDA PROMIS-PF4a or MDA PROMIS-PF Bank at each visit and overall using all observations (from left to right: visit 1, 2, 3, 4, and overall across visits)Conclusion:Excellent agreement was seen between HAQ-DI and PROMIS-based MDA definitions statically and longitudinally. The PROMIS-PF Bank and PROMIS-PF4a are accurate replacements for the HAQ-DI in calculating MDA state in PsA.