Evaluating Infection Independent Benefits of Influenza Vaccine in Older Adults Undergoing Surgery
Funded Grant
Overview
Affiliation
View All
Overview
description
Project Summary Age-related surgical complications pose significant risks for older adults. Recent evidence suggests that influenza vaccination may provide perioperative benefits beyond flu prevention, including reduced risk for cardiovascular events and other complications. However, the clinical-translational importance of these findings to older surgical patients remains unclear, partly due to potential confounding from "healthy vaccinee bias" and limited understanding of underlying mechanisms. This study aims to investigate how pre-operative influenza vaccination impacts post-operative outcomes in older adults using the TriNetX Federated Electronic Health Record database (n=2.4 million adults aged 65-90 years with major surgery, 2016-2024). We hypothesize that flu vaccination will drive a time-dependent reduction in risk of adverse post-operative events, including adverse cardiovascular events, deep venous thrombosis, and wound complications, and that vaccination will correlate with a signature of reduced post-surgical inflammation across diverse types of surgery. Our specific aims are to: 1) Compare post-operative complication risks between recently vaccinated and unvaccinated older surgical patients; 2) Evaluate time-dependent effects of flu vaccination on post-operative complications; and 3) Determine how timing of vaccination influences post-operative inflammatory markers. All aims will utilize a retrospective cohort design. When treating flu vaccination exposure as a dichotomous variable, we will use propensity score matching for demographic characteristics, clinical factors, and social determinants of health. When performing time-dependent analysis to evaluate impact of vaccination timing within 12 months pre- surgery on post-operative outcomes, we will use Cox models to define the relative reduction in the likelihood of the event of interest occurring, estimated by fitting a smooth function of time since vaccination. The primary clinical outcome will be major adverse cardiovascular events (MACE) within 30 days post-surgery, with secondary outcomes including deep venous thrombosis, pulmonary embolism, and wound complications. Post- operative inflammatory signatures will be assessed using routine clinical labs including complete blood count parameters, cell differentials, and C-reactive protein concentration. This research will advance understanding of how pre-operative flu vaccination might reduce post-operative complications in older adults. Findings will inform future interventional studies and could lead to simple, cost-effective strategies to improve surgical outcomes in this vulnerable population. The project will also support the development of a clinician-researcher focused on translational studies of immunomodulatory interventions for older surgical patients.
