S1267 History of Bariatric Surgery Portends Better Outcomes with COVID-19 Disease: Propensity Matched Analysis of a Large Multi-Institutional Research Network

Abstract

Introduction: Previous data has pointed towards worse outcomes with COVID-19 disease in the presence of obesity. Through sustained weight loss and improvement in metabolic co-morbids, a history of bariatric surgery may be hypothesized to reduce the risk of severe COVID-19 disease. However, the outcomes of COVID-19 disease in patients with obesity have not been explored. Methods: We conducted a retrospective cohort study on the multi-institutional research network TriNETX. Patients with COVID-19 were identified and divided into cohorts based on history of bariatric surgery (BS cohort and non-BS cohort). Clinical outcomes were compared in unmatched and propensity score matched analyses with patients matched 1:1 based on known risk factors of severe COVID-19 disease. Patients with no history of bariatric surgery but with clinical attributes qualifying for these procedures were identified and included in a ‘bariatric procedure qualifying’ group for sensitivity analysis. Results: Unmatched analysis revealed lower risk of mechanical ventilation or mortality at 30 days after COVID-19 diagnosis in the BS cohort compared to the non-BS cohort (1.07% vs 2.58%, Risk Ratio 0.41, 95% CI: 0.26 – 0.65). Lower risk of need for mechanical ventilation and lower mortality was noted in the bariatric surgery cohort. In the propensity score matched analysis, there was lower risk of reaching primary endpoint of mechanical ventilation or mortality in the BS cohort compared to the non-BS cohort (1.07% vs 3.09%, RR 0.35, 95% CI: 0.21 – 0.58). Mortality rate was lower in the BS cohort, and patients in the BS group were less likely to require critical care, mechanical ventilation, or develop acute kidney injury after COVID-19 diagnosis Log Rank tests revealed worse survival in both matched and unmatched analysis in the non-BS cohort when compared to the BS group (Log rank p values < 0.01 for all analyses). Subgroup analysis was performed comparing the RYGB and sleeve gastrectomy subgroups. No difference was noted in any clinical outcome on unmatched or matched analysis. On sensitivity analysis comparing BS group with BS qualifying cohort, lower rate of mortality, mechanical ventilation, need for critical care was noted in BS cohort (Table 1). Conclusion: In CONCLUSION:, our propensity matched analysis of a large cohort, we have found that a history of bariatric surgery is associated with a reduced risk of poor outcomes of COVID-19 disease compared to a cohort of obese patients as well as the general population.Figure 1.: (a-d) showing Kaplan Maier curves for Mortality (a and b) and compositive outcome (c and d) before (a and c) and after (b and d) propensity score matching for the bariatric surgery (purple) and the non-bariatric surgery (blue) cohorts.Table 1.: Outcomes in the two cohorts of COVID-19 patients with history of bariatric surgery and without bariatric surgery before and after propensity score matching.