Exploring physical function and physical activity in axial spondyloarthritis: Beyond clinical remission or low disease activity

Abstract

Objectives: To investigate the crucial roles of physical function (PF) and physical activity (PA) in axial spondyloarthritis (axSpA) patients, as well as their correlation with disease activity (DA), and to explore the influence of general characteristics among them.

Methods: We enrolled axSpA patients from Xijing Hospital, spanning March 2022 to August 2022. Spearman rank correlation coefficients were used to assess correlations between PA (measured by the Global Physical Activity Questionnaire [GPAQ]), PF (measured by the Assessment of Spondyloarthritis international Society Health Index [ASAS-HI], the Short Form 36-Item Health Survey [SF-36], and the Bath Ankylosing Spondylitis Functional Index [BASFI]), DA, and their influencing factors. A Mann-Whitney U-test and Kruskal-Wallis H-test were used to compare variables between different patients grouped by sex, human leukocyte antigen B27 (HLA-B27), hip involvement, and intensity of PA and DA.

Results: Three hundred fifty-five axSpA patients were included. We observed a moderate to strong correlation between DA and PF in axSpA patients. PA was weakly correlated with DA or PF. DA varied significantly at different PA levels, and patients with low PA levels had poorer PF. Active patients had worse PF, less transport-related PA, and a higher rate of hip involvement with a worse Harris Hip Score (HHS).

Conclusions: We identified a close relationship between DA, PF, and PA in axSpA patients. Further, gender, HLA-B27, and hip involvement affected the clinical manifestation of axSpA patients. These findings demonstrate that clinical remission of axSpA patients requires a comprehensive assessment rather than a single remission of DA.

Keywords: axial spondyloarthritis; disease activity; physical activity; physical function; quality of life.