Ab1306 epidemiology of acute anterior uveitis, psoriasis, inflammatory bowel disease, palindromic rheumatism and sjogren’s syndrome in treated ankylosing spondylitis patients in taiwan
Authors: H.-H. Chen, D.-Y. Chen, T.-Y. Hsieh, K.-L. Lai, Y.-M. Chen, C.-W. Tseng, C.-T. Lin
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> The population-based epidemiology of extra-articular manifestations of ankylosing spondylitis (AS), including acute anterior uveitis (AAU), psoriasis (PsO), inflammatory bowel disease (IBD) in Taiwan had not been investigated. Whether or not the incidences of palindromic rheumatism (PR) and Sjogren's syndrome (SS) are higher than non-AS individuals is also unknown. <h3>Objectives</h3> This study aimed to investigate the incidences of AAU, PsO, IBD, PR, and SS in a population-based AS cohort compared with a matched non-AS cohort in Taiwan. <h3>Methods</h3> Using 2003–2012 claims data from the Taiwanese National Health Insurance Research Database, we firstly identified 30,900 AS patients newly-diagnosed from 2006 to 2012 who received at least 3 courses of AS-related therapy (i.e., non-steroidal anti-inflammatory drugs, methotrexate, salazopyrine or corticosteroid) and defined the first date of AS diagnosis as the index date of the AS cohort. Then we randomly selected 3 09 000 non-AS individuals matching (1:10) AS cases for age, sex and the year of the index date as the comparison cohort and defined the first ambulatory visit date of the index year as the index date of the non-AS cohort. We calculated the proportions of having AAU, PsO, IBD, PR, and SS before the index date in both cohorts. After excluding subjects with the corresponding prior diseases, we calculated the incidence rates (IRs) of AAU, PsO, IBD, PR and SS for the AS and non-AS cohorts, and estimated the incidence rate ratios (IRRs) with 95% confidence intervals (CIs) of AAU, PsO, IBD, PR, and SS for AS patients as compared to non-AS individuals. <h3>Results</h3> The proportion of men was 62.9%, and the mean ±SD age was 42±17 years. Before the index date, AS patients had higher proportions of having AAU (8.6% vs. 0.7%), PsO (1.8% vs. 0.5%), IBD (0.061% vs. 0.007%), PR (1.7% vs. 0.1%) and SS (0.33% vs. 0.042%) compared with non-AS individuals. AS patients also had higher incidence rates of AAU (IR, 992 per 10<sup>5</sup> years vs. 128 per 10<sup>5</sup> years; IRR, 7.74, 95% CI, 7.16–8.38), PsO (IR, 167 per 10<sup>5</sup> years vs. 73 per 10<sup>5</sup> years; IRR, 2.30; 95% CI, 1.97–2.70), Crohn's disease (IR, 2.7 per 10<sup>5</sup> years vs. 0.2 per 10<sup>5</sup> years; IRR, 16.44; 95% CI, 2.75–98.4), ulcerative colitis (IR, 6.1 per 10<sup>5</sup> years vs. 0.1 per 10<sup>5</sup> years; IRR, 76.03; 95% CI, 9.35–617.98), PR (IR, 591 per 10<sup>5</sup> years vs. 29 per 10<sup>5</sup> years; IRR, 20.33 95;% CI, 17.87–23.12), and SS (IR, 84 per 10<sup>5</sup> years vs. 6 per 10<sup>5</sup> years; IRR, 13.61; 95% CI, 10.05–18.43). <h3>Conclusions</h3> Consistent with prior studies, our data showed that the incidence of AAU, PsO, and IBD were higher in AS patients than non-AS individuals. We also found that AS patients had a higher incidence of PR and SS compared with non-AS individuals. <h3>Reference</h3> [1] Stolwijk C, Essers I, van Tubergen A, et al. The epidemiology of extra-articular manifestations in ankylosing spondylitis: a population-based matched cohort study. Ann Rheum Dis2015;74:1373–8. <h3>Acknowledgements</h3> The authors would like to thank the Biostatistics Task Force of Taichung Veterans General Hospital, Taichung, Taiwan, ROC for statistical support. <h3>Disclosure of Interest</h3> None declared