Changes in health-related quality of life: a longitudinal registry study among over 15,000 participants of a digital education and exercise therapy for knee and hip osteoarthritis using EQ-5D-5L.

OBJECTIVE: To explore changes in health-related quality of life (HRQoL) measured using EQ-5D-5L among participants of a digital education and exercise therapy for knee and hip osteoarthritis (OA). METHODS: A descriptive longitudinal registry-based study among participants aged 40 + years enrolled in the digital program with responses to EQ-5D-5L at enrolment and at least one follow-up at 3- [n = 15147] or 12-months [n = 4586]. Changes in EQ-5D-5L profile from enrolment were examined using the Paretian classification of health change (PCHC). RESULTS: At enrolment, selfcare and pain/discomfort were the EQ-5D-5L dimensions with the least and most reported problems, respectively. The percentages of participants reporting improvements in EQ-5D-5L dimensions ranged from 12.9% (14.0%) for selfcare to 33.0% (38.4%) for pain/discomfort at 3 (12) months follow-ups. The corresponding percentages in reporting worsening ranged from 8.0% for selfcare to 15.4% for usual activities at 3 months and from 10.0% for selfcare to 16.4% for mobility at 12 months. At all timepoints, "slight problems" in the pain/discomfort dimension and no problems in other dimensions (the EQ-5D-5L profile "11121") was the most common profile. The PCHC analysis suggested that at 3/12 months follow-ups, the EQ-5D-5L profiles improved for 46.9%/50.4% of participants, worsened for 19.5%/20.1%, showed mixed changes for 19.7%/18.7% and remained unchanged for 13.9%/10.9%. CONCLUSION: In this single-arm registry study, about half of participants reported improved EQ-5D-5L profiles at 3 and 12 months following digital education and exercise therapy, while one-fifth reported worsening and another one-fifth showed mixed changes, indicating heterogeneous HRQoL trajectories and the need for tailored participant support.