Retinal Ganglion Cell Dysfunction in Glaucoma Suspects with Obstructive Sleep Apnea

Abstract

Purpose :
To investigate the presence of retinal ganglion cell (RGC) dysfunction in glaucoma suspects (GS) with obstructive sleep apnea (OSA) compared to GS controls, using Pattern electroretinogram (PERG)

Methods :
Nine glaucoma suspects (18 eyes) were enrolled in the cross-sectional study conducted at Manhattan Eye Ear & Throat hospital. Four participants (8 eyes) with OSA and five (10 eyes) well matched controls without OSA received comprehensive clinical evaluation, PERG and Optical coherence Tomography tests.
Independent samples t-test and linear stepwise regression analyses were used in the analyses. To predict each PERG parameter [Magnitude (Mag), MagnitudeD (MagD), and MagD/Mag ratio], we adjusted for age and sex in the first step, Intraocular pressure (IOP) in the 2^nd step, and OSA in the 3^rd step.

Results : Independent samples t-tests revealed no significant differences between 2 groups on age, intraocular pressure, central corneal thickness, spherical equivalent, macular thickness average cube, average retinal nerve fiber layer, average ganglion cell layer (aGCL+ IPL) thicknesses. When compared to controls, participants with OSA showed significantly decreased Mag (1.33 ± 0.32 vs 2.58 ± 0.61), MagD (1.09 ± 0.39 vs 2.39 ± 0.52) and MagD/Mag Ratio (0.81 ± 0.14 vs 0.93 ± 0.04). In the prediction of Mag, after controlling for age and sex (1^st step), and IOP (2^nd step), OSA (3^rd step) explained an additional 19.8 % of the variance in Mag (B=-0.87 (95% CI:-1.44, -0.30), p= 0.005). In the prediction of MagD, after controlling for age and sex (1^st step), and IOP (2^nd step), OSA explained an additional 21.8% of the variance in MagD (B=-0.91 (95% CI: -1.42, -0.40), p=0.002). IOP did not explain any variance and OSA did not explain any variance in MagD/Mag Ratio

Conclusions :
PERG demonstrates early RGC dysfunction in GS with OSA when compared to GS controls. OSA contributes to RGC dysfunction by mostly altering their intrinsic mechanisms (latency) above and beyond the effects of IOP. These findings highlight the importance of PERG testing in these patients. More studies are needed in assessing the effects of OSA treatment in GS and low tension glaucoma patients, using PERG technology.

This is a 2020 ARVO Annual Meeting abstract.