P071 Exercise as an anti-inflammatory treatment in axial spondyloarthritis (axSpA): a proof-of-concept study
Authors: Roberts Matthew , Hamrouni Malik , Linsley Victoria , Moorthy Arumugam , Bishop Nicolette 
Published: April 2023

Abstract

Background/Aims
Axial spondyloarthritis (axSpA) is an inflammatory arthritis affecting 0.5-1.0% of people in the UK. The inflammatory profile with axSpA causes pain and loss of mobility but can also contribute to other manifestations such as cardiovascular disease (CVD). Current management of axSpA relies on biologic medication; however, they are expensive, and effectiveness is influenced by disease duration, baseline inflammation and age. Monocytes, a type of white blood cell, express the cell surface markers CD14 ++CD16- (classical), CD14 ++CD16 + (intermediate), and CD14+CD16 ++ (non-classical). CD16+ monocytes are pro-inflammatory and are elevated in populations with CVD. Importantly, regular exercise reduces the relative proportion of CD16+ cells in other populations, but this is unknown in axSpA. Therefore, the present randomised control trial investigated whether exercise reduced the relative percentage of CD16+ monocytes in response to 12-weeks of home-based walking. Subjective measures of disease activity, physical function, spinal pain, and work productivity are included to supplement the findings.

Methods
20 participants (10 control, 10 exercise; 8 vs 7 presented here due to ongoing data collection) were recruited, provided written informed consent, and completed baseline assessments before being assigned into a control or exercise group. The control group carried on as normal. The exercise group completed 5 x 30-minute bouts of ‘somewhat hard’ walking per week which was confirmed via heart rate monitoring and a rating of perceived exertion scale. At baseline (week 0) and follow-up (week 12), participants completed questionnaires to assess BASDAI, BASFI, ASAS-HI, WPAI, and spinal pain. Blood samples were also collected for the analysis of monocyte subsets. Data were analysed using a two-way mixed analysis of variance (ANOVA) with time as the within factor. Statistical significance was accepted as P &lt; 0.05. However, description of trends is used throughout due to this being preliminary data with a small sample size.

Results
Group-by-time interactions revealed a significant reduction in the proportion of non-classical monocytes in the exercise group and an increase in the control group (P &lt; 0.001). This coincided with a significant interaction for the proportion of less inflammatory classical monocytes, with an increase in the exercise group and decrease in the control group (P &lt; 0.001). Overall, the exercise group also responded more favourably for BASDAI (P = 0.026) and spinal pain (P = 0.088) than the control group.

Conclusion
Preliminary findings suggest regular walking reduces pro-inflammatory immune cell populations in axSpA which coincides with favourable BASDAI and spinal pain responses compared to a control group. This highlights the importance of regular exercise to improve underlying inflammatory profiles in patients with axSpA.
Disclosure
M. Roberts: None. M. Hamrouni: None. V. Linsley: None. A. Moorthy: Consultancies; A.M has received speaker fees from Lilly, Novartis, Galapagos and UCB. Grants/research support; A.M has received funding from the National Axial Spondyloarthritis Society for this work. N. Bishop: Grants/research support; N.B has received funding from the National Axial Spondyloarthritis Society for this work.