AB1351 PREVALENCE AND THE RISK FACTORS OF TUBERCULOSIS (TB) AMONG PATIENTS WITH CONNECTIVE TISSUE DISEASE IN MALAYSIA: A MULTI-ETHNIC STUDY
Authors: M. Alagappa @ Arunachalam, S. S. Shaharir, A. Y. L. Ban, A. Noor Aizuddin, L. Kamaruzaman, N. Kori, M. S. Mohamed Said, S. Rajalingham
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Patients with connective tissue disease (CTD) are at risk of opportunistic infection, including Tuberculosis (TB) due to the impaired immunity and exposure to the immunosuppressants. Tuberculosis remains as a major health threat in Malaysia but there is a scarce data on the prevalence and their associated factors among the multi-ethnic Malaysian CTD patients. <h3>Objectives:</h3> To determine the prevalence of tuberculosis (TB) among patients with CTD in Hospital Canselor Tuanku Muhriz (HCTM), Universiti Kebangsaan Malaysia and their associated risk factors. <h3>Methods:</h3> This study was a single-centre retrospective review study which included CTD patients who attended HCTM from January 2010 to June 2022. This study was conducted from February 2022 until September 2023 and has obtained ethics approval from UKM Medical Research Ethics Committee (FF-2022-032). Patients were identified from the HCTM International Centre of Casemix and Clinical Coding (ITCC), and from the Rheumatology unit database. Their medical records were retrieved and reviewed using convenient sampling method. Patients with TB infection at the onset or after the CTD diagnosis were categorized as TB group while patients who had never had TB were categorized as non-TB group. For TB group, the baseline demographics, clinical characteristics, treatment and co-morbidities were censored at the time of TB diagnosis while for non-TB group, the data was collected until the last date of follow-up review. Pearson's chi square and Fisher's Exact test was performed for categorical variables while independent t- test and Mann-Whitney for continuous variable. Multivariable logistic regression analysis was performed to determine the independent factors associated with TB in CTD. <h3>Results:</h3> A total of 492 patients with CTD were included, which comprised of 231 (47%) SLE, 177 (36%) RA and 84 (17.1%) others. This multi-ethnic cohort consisted of majority Chinese patients (n=238, 48.4%), followed by Malay (n=184, 37.4%) and Indian &amp; others (n=70, 14.2%). The prevalence of tuberculosis in this cohort was 10.0% (n=49), with no significant difference between Systemic Lupus Erythematosus (SLE), Rheumatoid Arthritis (RA) and others (10% vs 9% vs 11.9%, p=0.77). In the age-adjusted multivariable logistic regression analysis, Malay ethnic (OR 6.4), use of oral prednisolone ≥ 7.5mg OD ever (OR 10.7), use of ≥ 2 immunosuppressants ever (OR 3.3) and hypoalbuminemia (OR 3.7) were the independent risk factors for TB in CTD. The use of cyclosporine A and dyslipidaemia were protective against TB in CTD (OR&lt;1). Significantly higher proportion of patients who had ever used biologics ie Rituximab (10.2 vs 1.8%, p=0.006) and anti-tumor necrosis factor-α had TB (6.1% vs 1.4%, p=0.05), but these factors were no longer significant in the multivariate analysis. <h3>Conclusion:</h3> The prevalence of TB in this cohort is approximately 10%. The use of oral prednisolone ≥ 7.5mg OD ever and use of ≥ 2 immunosuppressants ever were among the risk factors of TB. Further studies are needed to determine the risk and benefit of screening and treatment for latent TB in this high-risk group, as the use of isoniazid and/or rifampicin may increase the risk of hepatotoxicity and multi-drug resistant TB. The use of anti-TNF and Rituximab were no longer the significant risk factors in the multivariate analysis and this could be due to the small number of subjects who had received the treatments in this cohort. Therefore, a larger prospective cohort studies is warranted to confirm the risk factors in a CTD with different types of CTD and treatments. <h3>REFERENCES:</h3> [1] Sundaram K, Vajravelu LK, Velayutham R, Mohan U. Progression of tuberculosis among patients with rheumatic diseases – A systematic review and meta-analysis. Indian Journal of Tuberculosis. 2023. [2] Tang G, Chen X, Han Y, Peng Q, Liu J, Liu Y, et al. Clinical characteristics and related influencing factors of common rheumatic diseases concomitant with tuberculosis. Frontiers in Public Health. 2023;10. <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> Meenakshi Alagappa @ Arunachalam: None declared, Syahrul Sazliyana Shaharir Novartis, Novartis, Astra Zeneca, Astra Zeneca, Andrea Yu-Lin Ban: None declared, Azimatun Noor Aizuddin: None declared, Lydia Kamaruzaman: None declared, Najma Kori: None declared, Mohd Shahrir Mohamed Said: None declared, Sakthiswary Rajalingham: None declared.