NEFL and obstructive sleep apnea syndrome: The relationship between NfL and parameters of hypoxemia in OSA patients suggest a different mechanism, potentially via increased oxidative stress and neuroinflammation causing neurodegeneration (Daulatzai, 2015; Snyder et al., 2017) and white matter disease (Rostampour et al., 2020; Zacharias et al., 2021), which may contribute to sleepiness (Xiong et al., 2017).