POS1253 MORTALITY RATE RELATED TO COVID - 19 IN RHEUMATIC AND MUSCULOSKELETAL DISEASES (RMDs)
Authors: D. Freites, I. Perez-Sancristobal, L. Lopez Pedraza, M. P. Álvarez Hernandez, I. Hernandez, J. I. Colomer, A. Madrid García, B. Fernandez, C. Vadillo, L. Rodriguez Rodriguez, A. Mucientes, L. León, L. Abasolo
Journal: Annals of the Rheumatic Diseases (2021)

Background: Spain has been one of the countries most impacted by the COVID-19 pandemic. Among Spanish patients, 56,799 deaths have been reported. Although we have been in this situation of pandemic for a year, studies that show risk mortality rates in patients with rheumatic diseases continue to be scarce. Objectives: In patients with rheumatic and musculoskeletal diseases (RMDs) and infected with Covid – 19, a) we want to assess the mortality rate (MR) related to COVID-19; and b) to analyze the role of RMDs in mortality risk. Methods: An observational longitudinal study was conducted during the epidemic peak in Madrid (1 st Mar to 20 th May2020). All patients attended at the rheumatology outpatient clinic of a tertiary hospital with a diagnosis of RMDs and SARS - CoV 2 infection were included (according to a medical diagnosis or confirmed with a positive SARS-CoV-2 PCR diagnostic test). All patients were included since the time of COVID-19 diagnosis. Main outcome: death related to COVID-19 infection. Independent variable: type of RMDs including: autoimmune (systemic autoimmune conditions (SAC) and inflammatory joint disease (IJD)) and non–autoimmune (mechanical diseases and inflammatory diseases (microcrystalline arthritis and tendonitis)). Covariates: sociodemographic, comorbidities, chronic use of corticoids prior to COVID-19 infection. Survival techniques were used to estimate the MR related to COVID-19, given per 1,000 persons-month with a 95% confidence interval [CI]. The time of observation comprised the elapsed time between the date of COVID-19 diagnosis of infection until the date of patient’s death, or end of study. Cox multiple regression analysis was run to examine the effect of autoimmune RMDs compared to non-autoimmune RMDs on mortality risk adjusted by sex, age and comorbidities. Results were expressed by Hazard Ratio (HR) and [CI]. Results: 406 patients were included with RMD and Covid – 19 infection with a total follow-up 642.5 patients-month. 69.21% were women with a mean age at diagnosis of 60 ± 15.26 years. The evolution time from the diagnosis of rheumatic disease was 8 ± 8.38 years. 26% had comorbidity at baseline. 25% were chronically on corticoids prior to the infection. Of the 406 patients, 244 (60.09%) had non-autoimmune RMD (157 mechanic, 87 inflammatory) and 162 (39.9%) (106 (65.43%) IJD, 56 (34.56%) systemic condition) had autoimmune RMD. Of the 406 patients, 45 (11%) died during the follow-up, being 12± 14 days the mean time from infection to death (P50: 6[2-12] and a maximum of 60 days). MR was estimated in 70.03 [52.28-93.79] per 1,000 persons-month. MR was higher for men (MR 105[68-163]) than for women (MR 55 [37.2-81.6]) and in older people (MR &lt;60: 4.4, [0.6-31.7]; MR 60-75 years: 38.7[17.3-86.2]; MR &gt;75Years: 486 [354-1668]). The HR of mortality in autoimmune RMDs compared to non-autoimmune RMDs did not achieved statistical significance (HR: 1.39 [0.77-2.5], p=0.27). After adjusting for confounders, we did not find higher risk of mortality among the different types of RMDs (HR autoimmune vs non-autoinmunes: HR: 1.12 [0.6-2.02], p=0.7; HR IJD vs SAC; 1.5 [0.6-3.6], p=0.34; HR non-autoimmune vs SAC: 1.1 [0.5-2.5], P=0.7). Age (HR: 1.12; [1.10-1.15], p&lt;0.001), and the presence of comorbidities (HR: 2.05; [1.08-3.89], p=0.027) increased the Mortality risk. Conclusion: In patients with RMD and COVID-19 infection, we found a mortality rate of 7 per 100 persons-month. This study shows that the mortality risk related to COVID-19 is similar between autoimmune and non-autoimmune diseases after adjusting by confounders. We also found that age and comorbidities are risk factors for mortality related to COVID-19 infection. References: [1]Jorge A, et al. Temporal trends in severe COVID-19 outcomes in patients with rheumatic disease: a cohort study. Lancet Rheumatol . Epub ahead of print 2021.. [2]Bonfá E, et al. How COVID-19 is changing rheumatology clinical practice. Nat Rev Rheumatol 2021; 17: 11–15. [3]Hyrich KL, Machado PM. Rheumatic disease and COVID-19: epidemiology and outcomes. Nature Reviews Rheumatology 2020; 17: 71–72. Disclosure of Interests: None declared