Objectives: Bath Ankylosing Spondylitis Patient Global Score (BAS-G) is a uni-dimensional scale that enables patients to evaluate the effects of their illness on their health. The aim of this study was to determine the impact of disease related outcomes on the BAS-G scores in patients with axSpA.
Methods: A total of 309 patients (56.6% of whom were male, mean age 44 ± 11) were included in the study. Socio-demographic characteristics (age, sex and education level) and clinical characteristics such as disease activity (BASDAI and CRP), spinal mobility (BASMI), functional status (BASFI), radiographic structural damage (mSASS, mNY, and BASRI-hip), and health related quality of life (SF-36 and ASQoL) of the patients were recorded at baseline. In addition, BASDAI total and each item score, BASFI, BAS-G, and CRP levels were collected at 6, 12, and 24 months.
Results: Female patients had significantly higher BAS-G scores (p = 0.037). Baseline BASDAI total score (p < 0.001) and all BASDAI item scores (p < 0.001 for each item), BASFI total score (p < 0.001), ASQoL total score (p < 0.001), and SF-36 PCS sum-score (p < 0.001) were moderately/highly correlated with BAS-G. Multivariate analysis revealed that back pain (BASDAI Q2) (p < 0.001) and the severity of morning stiffness (BASDAI Q5) (p < 0.001) were the main determinants of BAS-G in patients with axSpA. In 2-year follow-up, BASDAI Q1, BASDAI Q5, and BASFI scores were independent determinants of BAS-G in patients with axSpA.
Conclusion: According to the results of the present study, patients with axSpA mainly rely on morning stiffness and back pain to determine their global health status. Moreover, fatigue, severity of morning stiffness and function are the determinants of BAS-G during follow-up.