Risk of perioperative mortality and venous thromboembolism after total hip or knee arthroplasty with recent COVID-19 infection: an observational study from the Kaiser Permanente Northern California Database.

Background and purpose:  Limited data exist on venous thromboembolism (VTE) and mortality risk in patients undergoing primary total hip (THA) or knee arthroplasty (TKA) following recent COVID-19 infection. We aimed to evaluate whether the timing of COVID-19 infection affects postoperative VTE and mortality risk after THA or TKA.

Methods:  Adult Kaiser Permanente Northern California members undergoing elective THA or TKA from 2020-2022 were identified using internal procedure codes. 33,520 patients with or without SARS-CoV-2 within 6 months preoperatively were compared. Multivariate Poisson regression was used to calculate incidence rate ratios (RRs) adjusted for demographics, comorbidities, and Covid vaccination status. The primary outcome was 90-day VTE (deep venous thrombosis or pulmonary embolism). The secondary outcome was 90-day mortality.

Results:  Among patients with recent COVID-19, the 90-day VTE rate was 0.3%, and the mortality rate was 2.5%. Recent COVID-19 within 6 to 12 weeks preoperatively did not significantly increase 90-day VTE risk (RR 1.0, 95% confidence interval [CI] 0.38-2.8) but was associated with increased 90-day mortality risk (RR 3.1, CI 1.7-5.4).

Conclusion:  Recent COVID-19 infection did not significantly impact VTE risk after THA or TKA. However, infection within 6 to 12 weeks preoperatively was associated with increased 90-day mortality.