The association of vascular risk factors with visual loss in giant cell arteritis.

Objective: Blindness is a recognized complication of GCA; however, the frequency of and risk factors for this complication have not been firmly established. The aim of this study was to examine the incidence and determinants of blindness in patients with GCA, using a large international cohort. Methods: The analysis was conducted among subjects recruited into the Diagnosis and Classification Criteria in Vasculitis Study. The study captures consecutive patients presenting to clinic-based physicians. New-onset blindness was assessed 6 months after diagnosis by completion of the Vasculitis Damage Index. Logistic regression analysis was used to assess the association between blindness and clinical variables. Results: Of 433 patients with GCA from 26 countries, 7.9% presented with blindness in at least one eye at 6 months. Risk factors identified at baseline for blindness at 6 months were identified and included prevalent stroke [odds ratio (OR) = 4.47, 95% CI: 1.30, 15.41] and peripheral vascular disease (OR = 10.44, 95% CI: 2.94, 37.03). Conclusion: This is the largest study to date of subjects with incident GCA and confirms that blindness remains a common complication of disease and is associated with established vascular disease. Trial registration: ClinicalTrials.gov, http://clinicaltrials.gov , NCT01066208.