AB0229 TRENDS IN LYMPHOMA PREVALENCE AND HOSPITAL OUTCOMES AMONG PATIENTS WITH UNDERLYING SYSTEMIC LUPUS ERYTHEMATOSUS: INSIGHTS FROM THE NATIONAL INPATIENT SAMPLE DATABASE
Authors: S. K. Gandhi, H. P. Patel, S. Kotia, T. S. Shaver
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Systemic Lupus erythematosus (SLE) is a well-recognized systemic autoimmune disease associated with an increased risk of malignancies, particularly lymphomas. Studies have indicated this risk to be as high as 4-7 times greater compared to the general population. This heightened risk is believed to stem from the disease process of SLE, specifically, the overstimulation of B cells combined with a defect in the immune system's surveillance, rather than solely from medications or other associated risk factors. Recent years have witnessed advancements in therapeutic approaches for SLE, leading to improved control of disease activity. This progress potentially influences the occurrence of Hodgkin's and non-Hodgkin's lymphomas in individuals with SLE. <h3>Objectives:</h3> To assess the trends in the prevalence of Hodgkin's and non-Hodgkin's lymphomas, as well as hospital outcomes in hospitalized patients with underlying SLE using the extensive National Inpatient Sample (NIS) database. <h3>Methods:</h3> The NIS is the largest publicly available all-payer inpatient healthcare database designed to generate United States regional and national estimates regarding inpatient utilization, access, cost, quality, and outcomes. Unweighted, it contains data from around 7 million hospital stays each year. Weighted, it estimates around 35 million hospitalizations nationally. For our analysis, we utilized data spanning from 2009 to 2019. After appropriate filtering of hospitalizations using ICD-9 CM/ICD-10 CM codes, we included hospitalizations of individuals over 18 years old with a primary diagnosis of SLE and a secondary diagnosis of Hodgkin's and non-Hodgkin's lymphoma were included. The analysis accounted for NIS clustering, survey design, stratification, and weights. Categorical data were presented as frequencies and percentages, while continuous variables were expressed as means with standard deviations. To assess trends in lymphoma prevalence among SLE hospitalizations, we employed the Jonckheere-Terpstra trend test. Additionally, we evaluated various hospital outcomes for the cohort, focusing primarily on in-hospital mortality, and secondarily on age, length of hospital stay in days, and cost of care in US dollars. Categorical and continuous variables were analyzed using the Pearson chi-square test and Wilcoxon rank-sum test, respectively. Statistical significance was determined at a p-value of &lt;0.05 for all conducted tests. All analyses were conducted using SAS, version 9.4 (SAS Institute Inc.). <h3>Results:</h3> Identified over a decade, from 2009 to 2019, a total of 25,107 patients had a primary diagnosis of SLE along with secondary diagnoses of Hodgkin's or non-Hodgkin's lymphoma. Figure 1 displays the baseline comorbidities of the cohort. Figure 2 illustrates the trends in lymphoma prevalence. The average in-hospital mortality rate was 3.82% (959 patients), with an average age of hospitalization being 60.61 years, an average length of stay of 6.86 days, and an average cost of hospital stay amounting to $17,479.55. <h3>Conclusion:</h3> The prevalence of lymphoma steadily increased from 6.15% in 2009, at the study's commencement, to a peak of 11.47% in 2019 when it concluded. This rise lacks a clear explanation. Possible reasons might include the persistent nature of lupus unaffected by medications, the heightened risk of malignancies due to immunosuppressive drugs, the common association of lupus with Sjogren syndrome strongly linked to lymphomas, or a combination of these factors. Further investigation is essential to uncover the root causes. Understanding these factors could enhance patient care and alleviate the considerable economic burden, exemplified by the approximate $17,000 cost incurred during a week-long hospital stay for these patients. <h3>REFERENCES:</h3> [1] Song L, Wang Y, Zhang J, Song N, Xu X, Lu Y. The risks of cancer development in systemic lupus erythematosus (SLE) patients: a systematic review and meta-analysis. Arthritis Res Ther. 2018 Dec 6;20(1):270. doi: 10.1186/s13075-018-1760-3. PMID: 30522515; PMCID: PMC6282326. <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> <b>None declared.</b>