Giant Cell Arteritis Following COVID-19 Vaccination: A Consumer-Stimulated Analysis.

Area of Science:

• Immunology
• Epidemiology
• Vaccinology

Background:

• Giant cell arteritis (GCA) is an immune-mediated vasculitis affecting large and medium arteries, primarily in older adults.
• Concerns arose regarding a potential association between GCA and coronavirus disease 2019 (COVID-19) vaccination, prompted by consumer reports and regulatory signals.

Purpose of the Study:

• To investigate the potential association between GCA and COVID-19 vaccination.
• To analyze GCA incidence in relation to COVID-19 vaccination using multiple Australian data sources.

Main Methods:

• Analysis of spontaneous GCA reports to SAEFVIC from January 2021 to September 2024.
• Application of self-controlled case series (SCCS) methodology to general practice and hospital datasets.
• Identification of GCA cases using diagnostic codes and keyword matching within a 1-42 day risk window post-vaccination.

Main Results:

• Six GCA cases were spontaneously reported post-vaccination, with four occurring within 42 days, all linked to the adenoviral vectored Vaxzevria® vaccine.
• No increased risk of GCA was observed in either the general practice or hospital datasets following COVID-19 vaccination (GP RI: 0.96; Hospital RI: 0.79).
• Analysis stratified by vaccine type, age, and sex did not reveal any increased GCA risk associated with COVID-19 vaccination.

Conclusions:

• This study, utilizing three Australian data sources, found no evidence of increased GCA presentations within six weeks of COVID-19 vaccination.
• The findings support informed decision-making for patients and clinicians regarding COVID-19 vaccination.
• The study strengthens the evidence base for COVID-19 vaccine safety.