The association between haemodialysis and optic neuropathy

Abstract

Purpose: Haemodialysis (HD) causes chronic intermittent haemodynamic disturbance. This study aims to identify the incidence of retinal nerve fibre layer thinning and visual field defect in patients receiving HD. Methods: Patients receiving at least 6 months of HD at Queen Mary Hospital Hemodialysis Unit between May 2011 and Mar 2015 were included. All patients were assessed at baseline, then annually for at least 3 years. During each visit, assessment of the cup to disc ratio (CDR), intraocular pressure (IOP), best corrected distance visual acuity (VA), central corneal thickness (CCT), Humphrey visual field (VF), optical coherence tomography (OCT) for retinal nerve fibre layer (RNFL) analysis were performed. Results: Fifty eligible subjects were included at baseline. Sixty-nine eyes in 38 patients with complete data were available for analysis at the final visit. There were worsening in VA, increase in CDR and increase in CCT, but the IOP remained unchanged. There was significant decrease in RNFL at baseline and at final visit in the nasal and inferonasal quadrants. No VF deterioration was noted after at least 3 years of HD. Conclusions: Our study showed that patients receiving HD developed thinning of RNFL in 2 quadrants over the course of at least 3 years. This is in line with the increased in CDR. Despite the possible structural deficit, there was no functional loss. Therefore, we would consider HD to be safe to the optic nerve although the more long-term effect of HD, especially those who already have compromised optic nerve, should be evaluated in further studies. This is, to the best of our knowledge, the first study to evaluate the risk of optic neuropathy development among patients on HD.