RISK FACTORS FOR NON-ARTERITIC ANTERIOR ISCHEMIC OPTIC NEUROPATHY IN SPECIALIZED EYE CENTERS IN IRAQ

Abstract

Background: Non-arteritic ischemic optic neuropathy (NAION) is the most common acute optic neuropathy and a common cause of sudden, painless loss of vision present commonly on awakening from sleep in patients over the age of 50 years. 

Aim: The aim of this retrospective case-control study was to assess the risk factors associated with NAION in an Iraqi population.

Patients and methods: This study was conducted in Baghdad, Iraq, from January 2020 to December 2021.  It was a retrospective case – control study and the cases included were those having new onset NAION and underwent thorough ophthalmological examination. Cases and control groups were evaluated for having hypertension, diabetes mellitus and hyperlipidemia and if they were smokers or not. 

Results: Patients with NAION had significantly more often diabetes mellitus (47.5% vs. 25%, P<0.001), hypertension (58.3% vs. 22.5%, P<0.001) and hyperlipidemia (15% vs. 5%, P=0.016). The presence of crowded optic disc and high IOP were significantly associated with the occurrence of NAION (crowded optic disc, OR 11.01, 95% CI 3.3-36.71, P<0.001; high IOP, OR 1.37, 95% CI 1.22-1.54, P<0.001). Diabetes mellitus, hypertension and hyperlipidemia had a strong correlation with NAION (diabetes, OR 2.25, 95% CI 1.11-4.57, P=0.024; hypertension, OR 5.78, 95% CI 2.73-12.2, P<0.001; hyperlipidemia, OR 8.59, 95% CI 2.43-30.28, P<0.001). Diabetes mellitus was seen significantly more often among persons with bilateral NAION (66.7% in bilateral vs. 41.9% in unilateral, P=0.023).

Conclusion: In this study we showed that crowded optic disc, high IOP, diabetes, hypertension and hyperlipidemia are associated with the onset of NAION.