Continuous Positive Airway Pressure Treatment May Improve Optic Nerve Function in Obstructive Sleep Apnea: An Electrophysiological Study.
STUDY OBJECTIVES
Obstructive sleep apnea (OSA) is a sleep disorder frequently associated with optic nerve diseases. Moreover, untreated patients with severe OSA may show optic nerve dysfunction as documented by electrophysiological studies using visual evoked potentials (VEP). Because continuous positive airway pressure (CPAP) treatment has proved to restore the physiologic nocturnal breathing, thus preventing nocturnal hypoxemia and reducing inflammation, in this study we tested whether 1-year CPAP treatment may modify VEP responses in patients with severe OSA.


METHODS
VEP were recorded at baseline and after 1 year of CPAP treatment in 20 patients with severe OSA, divided in two groups on the basis of CPAP adherence, and compared to a healthy control group.


RESULTS
Patients with good adherence to CPAP therapy (CPAP+; n = 10) showed VEP P100 amplitude significantly higher than patients with poor adherence to CPAP therapy (CPAP-; n = 10). Moreover, the CPAP+ group showed VEP responses similar to those in the control group (n = 26). Considering the mean difference of VEP responses between baseline and follow-up, the CPAP+ group showed a significant increase in VEP P100 amplitude and a significant decrease in VEP P100 latency compared to the CPAP- group.


CONCLUSIONS
This study documented that CPAP therapy significantly improves VEP in patients with OSA who are adherent to the treatment. We hypothesize that CPAP treatment, minimizing the metabolic, inflammatory and ischemic consequences of OSA, may normalize the altered VEP responses in patients with OSA by restoring and preserving optic nerve function.
['Liguori|Claudio|C|', 'Placidi|Fabio|F|', 'Palmieri|Maria Giuseppina|MG|', 'Izzi|Francesca|F|', 'Ludovisi|Raffaella|R|', 'Mercuri|Nicola Biagio|NB|', 'Pierantozzi|Mariangela|M|']
D000328:Adult D045422:Continuous Positive Airway Pressure D005074:Evoked Potentials, Visual D005260:Female D006801:Humans D008297:Male D008875:Middle Aged D009900:Optic Nerve D009901:Optic Nerve Diseases D017286:Polysomnography D020181:Sleep Apnea, Obstructive
optic nerve function OSA inflammation CPAP adherence VEP amplitude and latency intermittent hypoxemia