The role of antioxidant vitamins and selenium in patients with obstructive sleep apnea

Abstract

Purpose Obstructive sleep apnea (OSA) is a disorder characterized by recurrent episodes of obstruction of the upper respiratory tract during sleep often accompanied by oxygen desaturations. Antioxidant defense mechanisms are important to prevent OSAassociated diseases and decrease mortality. We aimed to determine the levels of selenium and vitamins A, C, and E in patients with OSA but without any comorbidities and compare the results with a control group, theorizing that the findings may be helpful to understand the antioxidant mechanisms in the pathogenesis of OSA and associated diseases. Methods We designed a case-control study with 146 subjects. Subjects were categorized into four groups by apneahypopnea index (AHI) scores: control (n = 32; AHI < 5), mild OSA (n = 32; 5 ≤ AHI < 15), moderate OSA (n = 34; 15 ≤ AHI < 30), and severe OSA (n = 48; AHI ≥ 30) groups. Serum levels of selenium were measured by atomic absorption spectrometer. Vitamin A, C, and E levels were measured by high-performance liquid chromatography and ultraviolet (HPLC-UV) detector. Results After adjusting for age, BMI, and gender, serum selenium and vitamin A levels were found to be higher in patients with OSA compared with controls (ANCOVA, p < 0.008, and p = 0.014 respectively), and levels of these markers increased with the severity of the disease. AHI was positively correlated with selenium (r = 0.289; p < 0.001), and vitamin A levels (r = 0.276; p < 0.001). Conclusion These results demonstrated that antioxidant response with increased vitamin A, and selenium concentrations, may be important defense mechanisms in patients with OSA patients who do not have other comorbidities. Antioxidant nutrients or supplements may be implemented as a complementary treatment of OSA to support antioxidant defense.

Oxidative Stress Markers among Obstructive Sleep Apnea Patients

“…Chen et al [72] demonstrated that selenium concentrations are decreased in newly diagnosed OSA patients with mild to moderate severity. In contrast, Saruhan et al [70] found significantly higher selenium levels in OSA patients compared with healthy subjects. In both studies, patients with comorbidities, which could impact the results, were excluded.…”

“…Several studies reported decreased levels of vitamins A and E in OSA patients compared with healthy individuals [68,69]. In contrast, Saruhan et al [70] found that concentrations of vitamin A are increased in OSA patients and are positively correlated with AHI. The levels of vitamin E were also higher in OSA patients compared with healthy individuals, but the difference was not statistically significant, possibly due to the different sample sizes of the groups used in the study (47 vs. 114).…”

“…Moreover, oxidative stress in OSA patients upregulates the expression of α-tocopherol transfer protein (αTTP), which is responsible for vitamin E transfer between the liver and other tissues [71]. However, the concentrations of vitamin C, a water-soluble compound, were significantly decreased in OSA patients compared with healthy subjects [70]. Opinions regarding the correlation between selenium levels and OSA also differ.…”

Selenium intake and cognitive function

“…First, There is a report that circulatory selenium concentration is significantly lower in patients with Alzheimer's disease and it is closely related to the level of an antioxidant enzyme, such as glutathione peroxidase [5]. Saruhan et al evaluated the association of serum selenium, vitamins A, C, and E with obstructive sleep apnea (OSA) by considering the antioxidant mechanisms in the pathogenesis of OSA [6]. Serum selenium and vitamin A levels were significantly higher in OSA patients, and there was a doseeresponse relationship between serum selenium concentration and the apnea-hypopnea index.…”

Association between Selenium Intake and Optimal Sleep Duration: A National Longitudinal Study

“…It has shown that low Se intake was associated with short sleep (5–6 h) compared with normal sleep (7–8 h) [ 16 ]. Furthermore, a case-control study published in 2020 has found that Se may be an important defense mechanism amongst patients with OSA without any comorbidities [ 17 ]. Rachel et al [ 18 ] also proposed that Se can be used to treat depression, which is the main symptom of sleep disturbance.…”