Recognising the threat of vision loss in people living with HIV on antiretroviral therapy without retinitis

Abstract

Background: People living with HIV (PLHIV) on antiretroviral therapy (ART) without retinitis may not have a healthy retinal structure. Aim: To examine the impact of the virus together with the ART medication in PLHIV without retinitis. Methods: This review used the following databases: PubMed, Google Scholar and EBSCOhost. Search terms included: HIV and/or retinal nerve fibre layer (RNFL); perimetry; colour vision; contrast sensitivity (CS); visual evoked potentials (VEPs); electroretinograms (ERGs); and the brain. All peer-reviewed studies related to PLHIV on ART without retinitis, up until September 2019, were included. Results: The mean RNFL thickness, and superior and inferior zones showed thinning. Affected visual functions include transient pattern VEP and ERG; contrast sensitivity; reduced total error scores on colour vision evaluation; and reduced mean deviation and pattern standard deviations on perimetry. Studies also showed concurrent thinning of the peripapillary retinal nerve fibre layer (ppRNFL) and perimetry, contrast sensitivity and colour vision. All these significant observations were seen at a cluster of differentiation 4 (CD4) count of less than 200 cells/mm3 in PLHIV on ART with no retinitis. Further to this, studies have also related the retina to grey and white matter changes in PLHIV in the era of ART. A gap in research involves studies on the vascular impact of ART on the retina, which should be factored into studies going forward when studying PLHIV on ART. Conclusion: The decrease in visual function, the RNFL changes and neuro-ophthalmic involvement in PLHIV allow us to recognise the threat to vision loss when factoring in the expected longer lifespan that PLHIV on ART are afforded today.

Keywords

• hiv
• retinal nerve fibre layer
• vision
• contrast sensitivity
• visual electrophysiology
• colour vision
• neuro-ophthalmic
• art