For a study, researchers wanted to find characteristics that were linked to EuroQoL–5 Dimensions, 5 Levels, Patient Acceptable Symptom State (PASS), and health utility (HU) in Thai patients with ankylosing spondylitis (AS). A cross-sectional study of AS patients who visited Siriraj Hospital between May 31, 2012, and March 31, 2016, was conducted. HU (Thai version of EuroQoL–5 Dimensions, 5 Levels), disease activity (Bath Ankylosing Spondylitis Disease Activity Index, Ankylosing Spondylitis Disease Activity Score–erythrocyte sedimentation rate or Ankylosing Spondylitis Disease Activity Score–C-reactive protein, number of tenders and swollen joints, and enthesitis), and functional status (Bath Ankylosing Spondylitis Functional Index, Factors linked with each EuroQOL–5 Dimensions (EQ-5D) dimension, HU, and PASS were investigated using regression analysis. 

The average age of the 119 AS patients was 40.4 years, with 61.3% of them being male. The average EQ-5D score was 0.75. Lower disease activity and less impaired function were substantially linked with greater HU and not moderate issues in each EQ-5D component in univariate analysis. Bath Ankylosing Spondylitis Disease Activity Index, C-reactive protein, and the Health Assessment Questionnaire adjusted for age explained 77.4% of the HU variation in multivariate regression analysis. Patients who said yes to PASS were substantially older had a higher HU, and had less disease activity than those who said no. After controlling for other domains like age, regular exercise, and pain difficulties were shown to be significantly linked to PASS.

In AS patients, disease activity and functional level were major determinants in HU and PASS. Treatment aims should include attaining remission, enhancing function, and reducing pain in order to enhance the quality of life.