Responsiveness of the EuroQoL 5-Dimension (EQ-5D) questionnaire in patients with spondyloarthritis

BACKGROUND: Spondyloarthritis (SpA) has a significant impact on patients’ quality of life due to functional impairments. Generic health instruments like the EuroQoL 5-dimension (EQ-5D) is important for cost-utility analysis of health care interventions and calculation of quality-adjusted life-years. It has been validated in patients with SpA. However, its responsiveness property is unclear. Hence, the aim of study is to test the responsiveness properties of the EQ-5D health measure for Chinese patients with SpA. METHODS: Prospective and consecutive recruitment of 151 Chinese patients with SpA was conducted with follow-up assessments 6 months later. Demographic data including smoking and drinking habits, education level, income and occupation was collected. Disease-associated data including disease duration, presence of back pain, peripheral arthritis, dactylitis, enthesitis, uveitis, psoriasis, and inflammatory bowel disease was also recorded. Questionnaires regarding disease activity and functional disability (BASDAI, BASFI, BASGI, BASMI, ASDAS), mental health (HADS) and the EQ-5D scores were recorded. Responsiveness was tested against the global rating of change scale (GRC) and changes in disease activity using BASDAI and ASDAS-CRP. RESULTS: A total of 113 (74.8%) patients completed the follow-up assessments. Most patients (61.6%) had low disease activity level with BASDAI <4 and 39.7% of patients had inactive disease by ASDAS-CRP. EQ-5D scores was well discriminated along with BASDAI and BASFI scores. EQ-5D scores also correlated well with HADS. The GRC was not able to discriminate adequately. No significant ceiling or floor effect was observed. CONCLUSIONS: EQ-5D demonstrates satisfactory responsiveness property for assessment of changes in SpA disease activity. LEVEL OF EVIDENCE: II