Oxidative stress and inflammatory profiles in obstructive sleep apnea: are short-term CPAP or aerobic exercise therapies effective?

Abstract

The effects of medium to long-term continuous positive airway pressure (CPAP) or physical activity in decreasing oxidative stress, inflammatory, and cell-free DNA markers in obstructive sleep apnea (OSA) have been explored. Here we evaluate oxidative stress markers (TBARS, AOPP, SOD), proinflammatory cytokines (TNF-α, IL-1β, IL-6, IL-8), anti-inflammatory cytokines (IL-4, IL-10), and cell-free DNA levels before and after 8-week CPAP treatment or moderate-intensity aerobic training in moderate to severe OSA. Thirty-nine patients diagnosed with OSA were randomly divided into CPAP (N = 18), with or without humidifier, and exercise groups (N = 21). Excessive daytime sleepiness and sleep quality were assessed by the Epworth Sleepiness Scale and the Pittsburgh questionnaire, respectively. Biomarkers for lipid and protein oxidation, pro and anti-inflammatory cytokines, and cell-free DNA were quantified in blood samples, before and after 8weeks of both treatments. After 8weeks of either CPAP or exercise, no significant differences were observed in the levels of cell-free DNA, oxidative stress, and inflammation markers, except for an increase in AOPP and IL-17A levels in individuals who went through CPAP, which were higher when the CPAP device was used without the humidifier. We have also observed that CPAP significantly decreased the Pittsburgh scores and improved sleep efficiency and hours of sleep, while ESS scores remained unaffected. Short-term treatment for OSA, be it CPAP therapy or moderate-intensity aerobic exercise, was not sufficient to alter either the oxidative stress and inflammatory profiles or the cell-free DNA levels of moderate to severe OSA patients. Short-term CPAP did, however, improve self-reported sleep quality.