Relationship between severity of obstructive sleep apnea syndrome and retinal nerve fiber layer thickness.

Purpose: To determine whether there is a significant correlation among the peripapillary retinal nerve fiber layer (RNFL) thickness, foveal thickness, total macular volume, and severity of obstructive sleep apnea syndrome.

Design: Prospective study.

Methods: We studied 124 consecutive subjects who underwent polysomnography. Optical coherence tomography (OCT) was used to measure the peripapillary RNFL, foveal thickness, and total macular volume. The Pearson correlation coefficient was used to determine the relationship between the apnea-hypopnea index and OCT and other parameters. Multiple regression analysis was used to determine the independent factors for the RNFL sectors that were the most strongly correlated with the apnea-hypopnea index.

Results: The apnea-hypopnea index was significantly and negatively correlated (right eye, r = -0.31, P = 0.0004; left eye, r = -0.39, P < 0.0001) with the nasal RNFL thickness (Pearson correlation analysis). The foveal thickness and total macular volume were not correlated. The intraocular pressure, body mass index, plaque score, and incidence of hypertension were negatively correlated, and the lowest oxygen saturation and mean oxygen saturation were positively correlated with the nasal RNFL thickness in the left eye. Multiple regression analysis showed that the apnea-hypopnea index and age were independent contributors to the nasal RNFL thickness in the left eye (apnea-hypopnea index, standard regression coefficient, -0.30, t value, -2.76, P = 0.007; age, -0.24, -2.36, 0.02, respectively). The nasal RNFL thickness in both eyes decreased significantly based on the severity of the obstructive sleep apnea syndrome.

Conclusion: Exacerbation of obstructive sleep apnea syndrome may produce unique retinal neurodegenerative disorders that decrease the nasal RNFL thickness.