Assessment of giant cell arteritis-associated visual outcomes at a tertiary hospital in Ontario, Canada

There are limited data concerning outcomes in those with giant cell arteritis-associated vision changes (GCA, GCAVCs). We estimated the association of intravenous, compared to oral, glucocorticoids with outcomes in GCAVCs. We conducted a retrospective cohort study at a tertiary healthcare facility in Ontario, Canada. Individuals aged 50 years or older with an international classification of disease version 10 (ICD-10) diagnostic code for GCA associated with a healthcare visit between November 2017 to December 2023 were identified for inclusion. Diagnoses of GCA were verified as the final diagnosis of the treating clinician and were required to be supported by histologic, radiographic, and/or biochemical evidence of inflammatory vasculopathy. GCAVCs were identified by clinical assessments. Treatment exposures were defined as whether the individual was first exposed to intravenous or oral glucocorticoids. The primary outcome was reported visual improvement after treatment. We used logistic regression to estimate treatment effects adjusting for demographic and disease factors. In 289 individuals with GCA, 77 (26.6%) had GCAVCs. 70.1% of GCAVCs led to permanent vision loss and visual recovery was seen in 16.0% of participants. We found no difference in outcomes for those first treated with intravenous versus oral glucocorticoids (adjusted odds ratios 0.43-1.72, 95% confidence interval range 0.02-123.68). GCAVCs are common and frequently associated with permanent vision loss. While the precision of our results was limited by sample size, we did not find evidence that IV before oral glucocorticoids was associated with visual improvement in GCAVCs.