Are Patients More Susceptible to Viral Illness Immediately Following Hip and Knee Arthroplasty? An Analysis of Influenza Diagnoses Using Multiple Administrative Databases

Elective surgery elicits a systemic immune response and may result in transient immunosuppression in certain patients. It is currently unknown whether patients are at increased risk for viral infection and associated illness in the immediate postoperative period following total joint arthroplasty (TJA).

Four large administrative datasets (Medicare 5% and 100% standard analytic files, Humana claims, and Mariner Database) were analyzed to identify patients who underwent total knee arthroplasty (TKA) and total hip arthroplasty (THA) from 2005 to 2017. The influenza vaccination status of each patient was defined using the presence or absence of a code for vaccination. The incidence of an influenza diagnosis was recorded in both vaccinated and unvaccinated patients during peak influenza season following the date of surgery and compared to a cohort of vaccinated patients who did not undergo surgery.

The incidence of postoperative influenza diagnoses in TKA and THA patients was similar to that of vaccinated patients who did not undergo TJA at all time points. The results were largely consistent across all datasets.

Large administrative databases fail to show an increased incidence of influenza in patients who have recently undergone TJA. While the lack of signal in the data is reassuring, 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.

Level III.