FRI0533 SMOKING AS A PREDICTIVE FACTOR FOR SPONDYLOARTHRITIS RELATED UVEITIS: RESULTS FROM A SINGLE CENTRE CROSS-SECTIONAL STUDY.
Authors: E. Costa, D. Almeida, M. Cerqueira, J. Redondo Costa, A. R. Ribeiro, J. Neves
Journal: Annals of the Rheumatic Diseases (2020)

Background: Although spondyloarthritis (SpA) is primarily a musculoskeletal condition, ocular involvement is an important clinical feature and contributes to the burden of disease. Acute anterior uveitis (AAU) is classically described as the most frequent extra-articular manifestation of SpA and in some cases the first clinical presentation. The prevalence of AAU varies according to the subtype of SpA. In a systematic literature review, the mean prevalence of AAU was 32.7% and a positive association between HLA-B27 positivity, axial SpA, male sex and uveitis has been reported (1). More recently, some cross-sectional studies have described lower odds of spondyloarthritis-related uveitis (SpA-U) in smokers than in patients who are ex smokers or never smokers (2). Predictors of SpA-U are poorly defined in literature and the influence of smoking status remains controversial. Objectives: To analyse the factors associated with uveitis in SpA patients in a Tertiary Rheumatology Center. Methods: An observational cross-sectional study was performed including patients fulfilling the ASAS criteria for axial SpA with a follow-up visit between January and June 2019. Clinical patients’ charts were reviewed and the following variables were considered: age, gender, history of uveitis (confirmed by ophthalmologist observation), number of AAU episodes, smoking status (never smoker or ever smoker), HLA-B27, disease duration, disease involvement (exclusively axial or axial and peripheral), history of enthesitis and syndesmophytes. History of AAU and associated variables were determined in this subset of patients. Statistical analysis was performed with logistic regression model. P value &lt;.05 was defined as statistically significant. Results: The study included 164 patients (62.3% men) with median age of 44.0 years (IQR 37 to 54) and a median disease duration of 14.6 years (IQR 9.28 to 20.32). SpA diagnosis was ankylosing spondylitis in 70.7% cases and the remaining were non-radiographic axial SpA. HLA-B27 was positive in 84.8%, 31.1% of patients were ever smokers and 21% had both axial and peripheral joint involvement. Twenty four percent of patients had at least one AAU episode. Recurrence of uveitis occurred in 70% of patients. Ever smoking (OR=2.256; 95%CI [1.077-4.276]; p&lt;.05) and syndesmophytes (OR=2.125; 95%CI [1.009-4.475]; p&lt;.05) showed a statistically significant association with uveitis in univariated logistic regression. Althougth not statistically significant, a trend to association was found between smoking and recurrence of AAU (OR=2.235; 95%ICI [.973-5.135], p=.058). In multivariated logistic regression only ever smoking was independently associated with uveitis (OR=2.542; 95%CI [1.007-6.420]; p&lt;.05). We did not find association between presence of uveitis and gender, age, disease duration, disease involvement, HLA-B27 positivity and enthesitis. Conclusion: Contrary to few cross-sectional studies showing a possible protective effect of smoking in SpA-U, and in line with new data from Zhao et al (3), we report a statistically significant independent association between history of smoking and uveitis. Nevertheless, we emphasize the need of more studies to confirm these findings. References: [1] Zeboulon N, et al. Prevalence and characteristics of uveitis in the spondyloarthropathies: a systematic literature review. Annals of Rheumatic Diseases 2008;67:955. [2] Zhao S, et al. Associations between smoking and extra-axial manifestations and disease severity in axial spondyloarthritis: results from the BSR Biologics Register for Ankylosing Spondylitis (BSRBR-AS). Rheumatology 2018;69. [3] Zhao S, et al. Smoking does not protect patients with axial spondyloarthritis from attacks of uveitis. Annals of Rheumatic Diseases 2019;78(9). Disclosure of Interests: None declared