Outcomes of NAION in Patients With and Without Diabetes Mellitus
Ophthalmology, April 2017
People with diabetes mellitus (DM) are known to have a greater risk of nonarteritic anterior ischemic optic neuropathy (NAION) than those without DM. Sharma et al. compared the visual outcomes, predictors of visual outcomes, and prevalence of bilateral/sequential NAION in these 2 groups of patients. The authors found that the visual acuity (VA) levels at presentation with NAION and at final follow-up were not significantly different between diabetic patients and nondiabetic controls, even though diabetic patients had a higher prevalence of cardiovascular risk factors.
Study participants included 30 patients with DM and 62 without DM (control patients) who presented within 4 weeks of onset of NAION symptoms. Of these 92 patients who completed baseline demographic assessments, 81 had clinical follow-up for ≥3 months and were included in the final visual outcomes. (Median follow-up duration was 38.7 weeks in diabetic patients and 52.9 weeks in nondiabetic patients.) The main outcome measure was visual acuity at last follow-up.
In nondiabetic patients, the most prevalent risk factor for NAION was hyperlipidemia (62.9%); for diabetic patients, NAION risk factors included hypertension (83.3%), hyperlipidemia (83.3%), and small cup-to-disc ratio (63.3%). Sequential NAION occurred in 36.8% of diabetic patients and 20.9% of nondiabetic patients. At last follow-up, 48% of diabetic and 62% of nondiabetic patients had VA better than 20/40. Similar proportions of diabetic and nondiabetic patients (8 [27%] diabetic and 14 [22.5%] nondiabetic patients) recorded a final follow-up vision of 1.0 logMAR or worse at a minimum of 3 months. Ischemic heart disease (odds ratio [OR], 7.21; p < .001) and greater age (OR, 1.05; p =.045) were associated with increased risk for final VA <20/200 in the multiple regression model (OR, 4.35; p = .011).
The researchers concluded that their analysis of VA outcomes in patients with NAION demonstrates that DM does not affect final VA, despite its association with increased NAION risk. Further, they found that ischemic heart disease may be an independent risk factor for worse final VA after the acute disease has resolved.
The original article can be found here.