Retinal sensitivity is reduced in patients with obstructive sleep apnea

Abstract

Purpose: To evaluate the outcomes of standard automated perimetry (SAP) in patients with obstructive sleep apnea (OSA).

Methods: Eighty OSA patients and 111 age-matched controls were consecutively and prospectively enrolled. One eye per subject was randomly selected. All participants underwent at least one reliable SAP (24-2 SITA Standard algorithm). The peripapillary retinal nerve fiber layer thickness (RNFL) was measured with spectral-domain optical coherence tomography (OCT). Patients with OSA were classified into three groups according to the apnea/hypopnea index: mild, moderate, or severe OSA. Parameters of SAP and OCT were compared between healthy controls and OSA patients. Correlation of apnea/hypopnea index with OCT and SAP measurements were calculated.

Results: Mean age, best-corrected visual acuity, and central corneal thickness were similar between groups. Intraocular pressure, however, was lower in the OSA group. Mean deviation of SAP was -0.23 ± 0.8 dB in the control group and -1.74 ± 2.8 dB in the OSA group (P < 0.001). Thickness of RNFL measured with OCT did not differ significantly between groups. Patients with OSA showed reduced sensitivity at most points tested by white-on-white perimetry compared with healthy individuals. The threshold values were more depressed in the peripheral visual field. The apnea/hypopnea index was related to the SAP indices: Pearson correlations were -0.432 with mean deviation, 0.467 with pattern standard deviation, and -0.416 with the visual field index (P < 0.001).

Conclusions: Patients with OSA exhibited reduced retinal sensitivity measured with SAP compared with healthy controls.

Keywords: obstructive sleep apnea; optic disc; optical coherence tomography; retinal nerve fiber layer; visual field.