Background: Nonarteritic anterior ischemic optic neuropathy (NA-AION) associated with optic disc drusen (ODD) is termed ODD-AION, where NA-AION with no evidence of ODD is simply termed NA-AION. Patients with ODD-AION have been found to be younger than those with NA-AION but with similar vascular risk factors. This study compares the known risk factors for NA-AION between a group with ODD-AION and a similarly aged group with NA-AION.
Methods: A case-control study of 13 patients with ODD-AION and 14 patients with NA-AION diagnosed in the period 2008-2017. All patients underwent an interview designed to evaluate history of vascular risk factors and comorbidities and re-examination including enhanced depth imaging optical coherence tomography to confirm the presence or absence of ODD.
Results: No significant differences were found in demographic or clinical characteristics between the ODD-AION and the NA-AION group. Significantly more ODD-AION patients than NA-AION patients had no vascular risk factors (smoking, arterial hypertension, diabetes mellitus, and dyslipidemia) present (P = 0.047). Significantly fewer patients in the ODD-AION group were diagnosed with arterial hypertension or dyslipidemia than in the NA-AION group.
Conclusions: In this cross-sectional study, the ODD-AION patients more often had no vascular risk factors as compared to NA-AION patients, which supports the hypothesis that ODD are an independent risk factor for AION.