The occurrence of optic disc haemorrhage in primary open-angle glaucoma eyes with lower normal pressure and its relating factors

Abstract

Purpose: To report the occurrence probability of disc haemorrhage (DH) and risk factors for it in otherwise healthy Japanese normal-tension glaucoma (NTG) patients who had lower normal intraocular pressure (IOP) and were followed without treatment for 5 years. Methods: A prospective observational study. Normal-tension glaucoma (NTG) patients with IOP consistently ≤15 mmHg without treatment were enrolled. The presence or absence of DH was checked semi-annually on the fundus photographs by three independent observers, while patients were followed without treatment. Cox proportional hazards model taking inter-eye correlation into consideration was adopted to identify risk factors for DH occurrence. The main outcomes were DH occurrence probability during 5-year period and its risk factors. Results: One hundred seventeen eyes of 90 patients with mean age of 54.1 years, mean deviation value of −3.6 decibels and mean IOP during follow-up of 12.4 mmHg were included. Disc haemorrhage (DH) was observed at least once in 34 eyes and more than twice in 15 eyes during the follow-up. The DH occurrence probability at 5 years was 31% (95% confidence interval: 21–40%), and lower myopic refraction (HR = 1.18; p = 0.018), higher IOP during follow-up (HR = 1.35; p = 0.047) and presence of DH at baseline (HR = 4.19; p = 0.002) were its risk factors. Conclusion: Disc haemorrhage (DH) occurrence probability of Japanese healthy NTG patients with mean IOP of 12.4 mmHg and no systemic and/or topical treatment was 31% at 5 years. Lower myopic refraction, higher IOP and its existence at baseline were its risk factors.