Updated guidance regarding the risk of allergic reactions to COVID-19 vaccines and recommended evaluation and management: A GRADE assessment and international consensus approach

This guidance updates 2021 GRADE (Grading of Recommendations Assessment, Development and Evaluation) recommendations regarding immediate allergic reactions following coronavirus disease 2019 (COVID-19) vaccines and addresses revaccinating individuals with first-dose allergic reactions and allergy testing to determine revaccination outcomes. Recent meta-analyses assessed the incidence of severe allergic reactions to initial COVID-19 vaccination, risk of mRNA-COVID-19 revaccination after an initial reaction, and diagnostic accuracy of COVID-19 vaccine and vaccine excipient testing in predicting reactions. GRADE methods informed rating the certainty of evidence and strength of recommendations. A modified Delphi panel consisting of experts in allergy, anaphylaxis, vaccinology, infectious diseases, emergency medicine, and primary care from Australia, Canada, Europe, Japan, South Africa, the United Kingdom, and the United States formed the recommendations. We recommend vaccination for persons without COVID-19 vaccine excipient allergy and revaccination after a prior immediate allergic reaction. We suggest against >15-minute postvaccination observation. We recommend against mRNA vaccine or excipient skin testing to predict outcomes. We suggest revaccination of persons with an immediate allergic reaction to the mRNA vaccine or excipients be performed by a person with vaccine allergy expertise in a properly equipped setting. We suggest against premedication, split-dosing, or special precautions because of a comorbid allergic history.

P2271Contemporary trends and outcomes of percutaneous vs. surgical aortic valve replacement in cancer patients

Importance

Cancer patients with severe AS are often ineligible for surgical aortic valve replacement (SAVR). Transcatheter aortic valve replacement (TAVR) is an emerging non-invasive treatment option for severe AS. Cancer patients likely stand to benefit from TAVR given its non-invasive nature; however, there is a paucity of data regarding the comparative effectiveness of TAVR vs. SAVR in cancer. We sought to assess the relative utilization, outcomes, and dispositions associated with TAVR vs. SAVR in cancer and non-cancer patients.

Methods

The US-based National Inpatient Sample was queried between 2012 and 2015 using ICD-9 codes for adults>18 years with comorbid AS and cancer without metastatic disease. Multiple in-hospital and disposition outcomes were evaluated. Comparison of TAVR vs SAVR required propensity score estimation using demographic, socio-economic, comorbidity, and hospital specific variables. A standardized morbidity ratio (SMR) weight was calculated by assigning TAVR a weight of 1, and those undergoing SAVR weight of PS/(1-PS). SMR-weighted generalized logistic regression was conducted to estimate the average effect of TAVR compared with SAVR. Finally, the Cochran–Mantel–Haenszel (CMH) test for propensity-matched data was utilized to compare the effect modification of cancer on these outcomes.

Results

A total of 979,912 out of 5,611,173 patients with AS were found to have non-metastatic cancer (17.5%). Average Elixhauser's mortality score of patients undergoing TAVR and SAVR was 8.9 vs. 8.1 and 8.5 vs. 7.1 for cancer vs. non-cancer respectively (p<0.0001). Over time, patients undergoing AVR increased in both groups, primarily driven by significantly increased rates of TAVR utilization in the cancer group. Over the study time period, an increase in the proportion of patients undergoing TAVR among all patients undergoing AVR was noted (figure) with 21.8% and 19.6% patient with prostate and breast cancer in 2015. TAVR in cancer patients was associated with lower odds of acute kidney injury [AKI; odds ratio (OR): 0.6, 95% confidence interval (CI): 0.5- 0.8], cardiogenic shock [OR: 0.6 (0.4–0.8)] and major bleeding [OR: 0.4 (0.3–0.5)] with no difference in in-hospital mortality and stroke compared to SAVR. Additionally, TAVR was associated with higher odds of home-discharge [OR: 1.9 (1.7–2.2)], and lower need for nursing facility transfer [OR: 0.7 (0.6–0.8) compared to SAVR among cancer patients. Similar outcomes are noted in the non-cancer cohort upon comparing TAVR to SAVR. However, favorable effect-modification of cancer was noted in regard to AKI (p=0.003), home discharge (p<0.0001), and less nursing facility transfer (p=0.0003), suggesting safety.

Conclusions

Compared to patients without cancer, the utilization of AVR in cancer patients has steadily increased. The benefits of TAVR over SAVR appear to extend to patients, regardless of cancer status. TAVR might be a more suitable procedure for cancer patients with AS.