Abstract
Introduction
Elective surgery elicits a systemic immune response and may result in immunosuppression in certain patients. It is currently unknown whether patients are at an increased risk for viral infection and associated illness in the immediate postoperative period following total joint arthroplasty. This question has become more important given the ongoing coronavirus disease 2019 (COVID-19) pandemic.
Methods
We analyzed 3 large administrative datasets (Medicare 5% and 100% standard analytic files, Humana claims database) to identify patients who underwent total knee arthroplasty (TKA) and total hip arthroplasty (THA) from 2005 to 2013. The influenza vaccination status of each patient was defined using the presence or absence of a code for vaccination. The incidence of a flu diagnosis was recorded in both vaccinated and unvaccinated patients at 1 month, 3 months, and 6 months following the date of surgery and was compared to a cohort of vaccinated patients who did not undergo surgery.
Results
The incidence of postoperative influenza diagnoses codes in TKA and THA patients were similar to that of vaccinated patients who did not undergo TJA at all time points. The results were largely consistent across all three datasets.
Conclusion
Large administrative databases fail to show an increased incidence of influenza codes in patients who have recently undergone total joint arthroplasty. While the lack of signal is reassuring and provides evidence, these findings are limited by the nature of large administrative datasets and the accuracy of coding for influenza. Further studies will be necessary to fully understand an individual patient's postoperative risk for contracting a viral illness.
