Effects of nasal continuous positive airway pressure treatment on oxidative stress and adiponectin levels in obese patients with obstructive sleep apnea.

BACKGROUND Obesity and obstructive sleep apnea (OSA) are both associated with the prevalence of major cardiovascular illnesses and certain common factors they are considered responsible for, such as stress oxidative increase, sympathetic tonus and resistance to insulin. OBJECTIVE The aim of the present study was to compare the effect of continuous positive airway pressure (CPAP) on oxidative stress and adiponectin levels in obese patients with and without OSA. METHODS Twenty-nine obese patients were categorized into 3 groups: group 1: 10 individuals without OSA (apnea-hypopnea index, AHI or=20) who did not use CPAP; group 3: 9 patients with moderate to severe OSA (AHI >or=20) who used CPAP. RESULTS Group 3 showed significant differences before and after the use of CPAP, in the variables of diminished production of superoxide, and increased nitrite and nitrate synthesis and adiponectin levels. Positive correlations were seen between the AHI and the superoxide production, between the nitrite and nitrate levels and the adiponectin levels, between superoxide production and the HOMA-IR, and between AHI and the HOMA-IR. Negative correlations were found between AHI and the nitrite and nitrate levels, between the superoxide production and that of nitric oxide, between the superoxide production and the adiponectin levels, between AHI and the adiponectin levels, and between the nitrite and nitrate levels and the HOMA-IR. CONCLUSIONS This study demonstrates that the use of CPAP can reverse the increased superoxide production, the diminished serum nitrite, nitrate and plasma adiponectin levels, and the metabolic changes existing in obese patients with OSA.