To facilitate communication of clinical study results among patients, clinicians, and payers, this post-hoc analysis examined the association between achieving the Health Assessment Questionnaire-Disability Index (HAQ-DI) clinical meaningful improvement (CMI) and normalization of individual daily activities using pooled clinical trial data of patients with moderate-severe psoriatic arthritis (PsA).

Patients with active PsA (n=1,120) who participated in two Phase III trials were administered the HAQ-DI at baseline and weeks (W) 24 and 52. The HAQ-DI is a patient-reported instrument measuring functional status that is validated for rheumatological diseases including PsA. It contains 20-items assessing activities of daily living using a 0-3 Likert scale [0=able to perform activity without difficulty (normalization) through to 3=unable to perform activity]; 0.35 or more improvement in total HAQ-DI represents the CMI in PsA patients. Study participants with baseline item-specific scores more than zero (indicating some level of impairment) who experienced both 0.35 or more improvement in total HAQ-DI and item-specific score equal to zero, were compared over time.

The proportion of patients with compromised ability to perform individual activities at baseline ranged from 42.3 percent (Difficulty Turning Faucet) to 84.1 percent (Difficulty Doing Chores). Fourteen of 20 activities with 60 percent or more of patients reporting impairment at baseline decreased to one of 20 activities in patients reaching the CMI at W24. Fourteen of 20 activities with 50 percent or more of patients reporting no impairment at W24 increased to 18 of 20 activities at W52. Notably, the proportion of patients reporting impairment for the two outlier activities at W52 (Reach-Get Down 5lb Item/Doing Chores) decreased during the follow-up period by 28 percent and 30 percent, respectively, despite presenting as very challenging at baseline.

PsA patients achieving a clinically meaningful change in total HAQ-DI over time were more likely to achieve normalization of individual daily activities. Translating changes in patient-reported outcome scores to specific symptom or functional improvements are meaningful to help patients understand clinical trial results, as well as to communicate with payers the value of accessing treatment for specific health conditions.