Positive Airway Pressure Treatment Effects on the Serum Nod-like Receptor Protein 3 and Nitric Oxide Levels in Obstructive Sleep Apnea Syndrome.

Objective: Obstructive sleep apnea syndrome (OSAS) is associated with recurrent apnea episodes. Positive airway pressure (PAP) treatment prevents repeatedly hypoxia in OSAS. Serum nitric oxide (NO) and Nod-like receptor protein 3 (NLRP3), that are involved in inflammation and pyroptotic cell death, may be affected hypoxia in OSAS. If so preventing hypoxia-ischemia episodes by PAP treatment may change serum NLRP3 and NO levels in OSAS. We aimed to determine whether serum levels of NLRP3 and NO change after at least 3 months of treatment with PAP.

Methods: Twenty-five OSAS patients, including 17 men and 8 women, who underwent polysomnography (PSG) and had an apnea-hypopnea index (AHI) of 30 or more and had started treatment at PAP. AHI was recorded. Serum levels NO and NLRP3 were analyzed before and at least 3 months after PAP treatment.

Results: After treatment with the PAP device, serum NO levels were significantly increased, NLRP3 levels were significantly decreased compared to pre-treatment levels (p < 0.001, p = 0.003). No correlation was found between serum NLRP3 and NO levels, AHI, type of the PAP device before or after PAP treatment.

Conclusion: We revealed that PAP treatment which prevents hypoxia, can alter the serum levels of NO and NLRP3 in OSAS, that is not related to the severity of AHI or type of the PAP device. This is the first study to measure NLRP3 levels before and after treatment with PAP in OSAS patients. Prospective studies with large cohorts and longitudinal follow-up evaluation of complications may provide further insights.