POS0185 TEMPORAL TRENDS IN MORTALITY IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS: A DANISH POPULATION-BASED MATCHED COHORT STUDY
Authors: S. Kristensen, K. S. Duch, B. G. Soussi, C. Jensina de Saint-Aubain, M. Laugesen, L. Dreyer
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Higher mortality has previously been shown in patients with systemic lupus erythematosus (SLE) compared to the general population. Given the recent therapeutic and organisational improvements in the management of SLE, increasing survival rates could be expected. <h3>Objectives:</h3> We aimed to investigate the overall and age-specific temporal trend in 5-year and 10-year all-cause mortality in a nationwide population-based matched cohort of incident patients with SLE. <h3>Methods:</h3> The study was conducted as a nationwide population-based matched cohort study. Incident patients with SLE diagnosed between 1996 and the end of 2015 were identified using nationwide administrative health registries and the cohort was followed until the end of 2020, allowing for 5 and 10 years of follow-up. SLE case definition was based on previously suggested algorithm requiring that the first registration of SLE in the Danish National Patient Registry should be followed by (a) out-patient follow up within one year or (b) consecutive inpatient admissions coded with an SLE diagnosis with minimum 3-month intervals during the first year of follow up. Patients with SLE were matched 1:5 on year of birth and sex with non-SLE individuals from the Danish general population. Time-to-event analyses were performed using the pseudo-observation approach. Generalized linear regression with robust variance estimator was used to estimate the risk difference (RD) and relative risk (RR) based on the pseudo-observations. <h3>Results:</h3> In total, 1351 incident patients with SLE and 6755 matched controls were identified. The crude RD for 5-year mortality decreased over the study period from 10.3% (95% CI 6.5 to 14.1%) to 4.6% (95% CI 1.4 to 7.8%) for patients with SLE when compared to the reference group. The 5-years mortality RR for patients with SLE decreased from 3.1 (95% CI 2.2 to 4.2) in 1996 to 2000 to 2.0 (95% CI 1.3 to 2.9) in 2011 to 2015 when compared to the matched control population. Adjusting for comorbidities revealed lower RD and RR for mortality but retained the decreasing pattern. Crude and adjusted RD and RR for 10-year mortality did not change over the calendar periods with persisting excess mortality in the late decade with adjusted RD of 7.2% (95% CI 2.6 to 11.9%) and adjusted RR of 1.5 (95% CI 1.1 to 2.0). The 10-year RR was highest in young patients in both the early (RR 3.6, 95% CI 1.9 to 6.7) and the late (RR, 4.9 95% CI 2.0 to 12.4) calendar periods. <h3>Conclusion:</h3> Five-year mortality risk decreased over time for both patients with SLE and matched controls. However, excess 5-year mortality in the most recent calendar period and mortality late in the disease persisted. Continued focus on preventing disease progression and comorbidities is needed. <h3>REFERENCES:</h3> <b>NIL.</b> <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> Salome Kristensen: None declared, Kirsten S. Duch: None declared, Bolette Gylden Soussi Bolette Gylden Soussi reports Novo Nordisk stocks, Constance Jensina de Saint-Aubain: None declared, Monika Laugesen: None declared, Lene Dreyer Lene Dreyer reports contract with BMS and AbbVie outside the submitted work; support for attending meetings and/or travel from Janssen, UCB, Boehringer Ingelheim; chair of the scientific committee of the Danish Rheumatism Association, member of DANBIO's steering committee, member ethical scientific committee in Denmark.