[Obstructive sleep apnea contribution to oxidative stress in obesity]. / Contribuição da apnéia obstrutiva do sono para o estresse oxidativo da obesidade.

OBJECTIVE: The aim of this paper was to check the influence of obstructive sleep apnea (OSA) on obesity oxidative stress and CPAP (Continuous Positive Airway Pressure) effect on oxidative stress and in these patients. METHODS: Twenty nine male patients considered obese (BMI > 30 kg/m(2)) were divided into 3 groups: a) Group I: 10 OSA free patients (apnea-hipopnea index (AHI) < 5); b) Group 2: 10 with moderate to serious OSA (AHI > 20); c) Group 3: 9 with OSA from moderate to serious (AHI > 20) using CPAP, minimum 4 hours/night for 2 months. RESULTS: Significant differences before and after CPAP usage were observed in group 3 in the following variables: reduction of superoxide (SO) production [13.2 (10.3-19.6) vs. 10.5 (5.8-11.8) nmoles O2(-)/2 x 10(6) PMN] and increase in serum nitrite/nitrates levels [24.5 (16.7-33.5) vs. 49.5 (39.3-58.1) microM]. Positive correlation between Apnea-Hypopnea Index (AHI) and SO (r = 0,726) and negative correlation was observed between AHI and serum nitrite/nitrates levels (r = - 0.867). CONCLUSIONS: In conclusion, oxidative stress present in obesity is elevated by OSA and CPAP treatment can rise the levels of SO and can decrease serum nitrite/nitrates present in obese patients with OSA.