Abstract
PURPOSE: This study investigated whether previous COVID severity and vaccination affected subsequent elective postsurgical mortality and readmission rates at 30, 90 and 365 days. METHODS: 21 855 veterans were divided into two cohorts, a no-COVID (NC) cohort of 19 338 patients and a previous COVID cohort of 2547 patients. Patients with acute COVID <22 days prior to surgery were excluded. COVID patients were further divided into 1776 Mild and 771 Moderate/Severe. Another comparison cohort was based on vaccinations. RESULTS: Patients with moderate/severe COVID had higher 30-day (5.9% vs. 3.5%, P = 0.003), 90-day (5.6% vs. 3.41%, P < 0.001), and 365-day mortality (6.07% vs. 3.23%, P < 0.001) than mild COVID or NC patients. They were also more likely to be readmitted (P < 0.001) than mild or NC. Mild COVID increased readmission risk by 16.6% (OR = 1.166). NC patients with no vaccine had higher mortality than vaccinated NC patients (log-rank, P < 0.01). Mortality in NC patients decreased with more time between vaccine dose and surgery (Breslow-Day P < 0.001). The only significant interaction was between mild COVID and time to vaccination predicting death (Breslow-Day P < 0.001). CONCLUSION: History of moderate/severe COVID, lack of COVID vaccination, and recency of COVID vaccination may be associated with higher elective surgery mortality and postsurgical readmission rates.