Objective: To investigate various aspects of nonarteritic anterior ischemic optic neuropathy (NA-AION) in patients with diabetes mellitus and to compare them with those in patients without diabetes mellitus.
Design: Cohort study.
Participants: A total of 655 consecutive patients (931 eyes) with NA-AION, first seen in the clinic from 1973 to 2000.
Methods: At the first visit, all patients had a detailed ophthalmic and medical history and comprehensive ophthalmic evaluation, including color fundus photography and fluorescein fundus angiography. Visual evaluation was done by recording visual acuity with the Snellen visual acuity chart and visual fields with a Goldmann perimeter. The same ophthalmic evaluation was performed at each follow-up visit, except for fluorescein fundus angiography. Of this cohort, 528 eyes (345 patients) were treated with systemic corticosteroid therapy during the initial stage.
Main outcome measures: Demographic and clinical differences between diabetic patients and nondiabetic patients with NA-AION.
Results: Comparison of various clinical features of NA-AION in diabetic and nondiabetic patients showed no significant difference in age, but slightly more women than men (45% vs 38%; P = 0.078) were diabetic and had a higher prevalence of hypertension (P<0.0001), ischemic heart disease (P = 0.0001), transient ischemic attacks (P = 0.0003), and second eye involvement by NA-AION (P = 0.003). Initial visual acuity did not differ significantly between diabetic and nondiabetic patients; however, of those seen within 2 weeks of onset of NA-AION, diabetic patients had less severe visual field defect (P = 0.010). At 6 months from onset, there was no significant difference in visual acuity and visual field improvement between diabetic and nondiabetic patients. Time to optic disc edema resolution in NA-AION was (P = 0.003) longer in diabetic patients than in nondiabetic patients. The optic disc of diabetic patients usually has characteristic diagnostic dilated telangiectatic vessels during the early stages of NA-AION.
Conclusions: Diabetic patients with NA-AION show several demographic and clinical differences from nondiabetic patients, which has led to controversy about its diagnosis and management.