Effects of obstructive sleep apnea on retinal microvasculature

To detect retinal microvascular variations in obstructive sleep apnea syndrome patients.

This prospective, observational case-control study included healthy controls and patients with mild, moderate, and severe obstructive sleep apnea syndrome. Vascular parameters, foveal avascular area, and flow areas in macula-centered, 6.00×6.00 mm² scan size optical coherence tomography angiography images were compared.

The control group had the highest whole image, parafoveal, and perifoveal vessel density among the groups in both superficial and the deep capillary plexus (all P<0.05). Rapid eye movement sleep apnoea-hypopnoea index was reversely correlated with whole (Rho=-0.195, P=0.034), parafoveal (Rho=-0.242, P=0.008), perifoveal (Rho=-0.187, P=0.045) vessel density in the superficial capillary plexus, and whole (Rho=-0.186, P=0.046), parafoveal (Rho=-0.260, P=0.004), perifoveal (Rho=-0.189, P=0.043) vessel density in the deep capillary plexus, though the mean and non-rapid eye movement sleep apnoea-hypopnoea index related with only parafoveal vessel density in the superficial capillary plexus (Rho=-0.213, P=0.020; Rho=-0.191, P=0.038) and the deep capillary plexus (Rho=-0.254, P=0.005; Rho=-0.194, P=0.035).

This study shows decreased vessel density and its reverse correlation with the apnoea-hypopnoea index in patients with obstructive sleep apnea syndrome.