Obstructive sleep apnea and Alzheimer's disease-related cerebrospinal fluid biomarkers in mild cognitive impairment.

Fecha de publicación: 21/01/2021 Fecha Ahead of Print: 07/07/2020

Autores de IIS La Fe

• Monica Diaz Roman

  Autor

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  Miguel Baquero Toledo

  Autor

• Alicia Salvador Fernández-Montejo

  Autor

• Ana Isabel Cuevas Jimenez

  Autor

• Inés Ferrer Cairols

  Autor

• Oana Gratiela Ciopat

  Autor

• Enriqueta Gomez Siurana

  Autor

Participantes ajenos a IIS La Fe

• Pulopulos MM

Abstract

Previous studies have demonstrated that sleep-breathing disorders, and especially obstructive sleep apnea (OSA), can be observed in patients with a higher risk of progression to Alzheimer's disease (AD). Recent evidence indicates that cerebrospinal fluid (CSF) AD-biomarkers are associated with OSA. In this study, we investigated these associations in a sample of patients with mild cognitive impairment (MCI), a condition that is considered the first clinical phase of AD, when patients showed biomarkers consistent with AD pathology. A total of 57 patients (mean age = 66.19; SD = 7.13) with MCI were included in the study. An overnight polysomnography recording was used to assess objective sleep parameters (i.e. apnea/hypopnea index [AHI], total sleep time, sleep efficiency, sleep latency, arousal index, awakening, stage 1, 2, and slow-wave sleep and rapid eye movement sleep, periodic limb movement index, O2 saturation during sleep, and percentage of time O2 saturation <90%). Phosphorylated-tau (P-tau), total-tau (T-tau), and amyloid-beta 42 (Aß42) were measured in CSF. Unadjusted correlation analyses showed that a higher AHI (reflecting higher OSA severity) was related to higher P-tau and T-tau (both results remained significant after Bonferroni correction, p = 0.001). Importantly, these associations were observed even after adjusting for potential confounders (i.e. age, sex, body mass index, sleep medication, smoking, hypertension, and heart disease). Although more research is needed to establish a causal link, our findings provide evidence that OSA could be related to the pathophysiological mechanisms involved in neurodegeneration in MCI patients.

Keywords

• Alzheimer’s disease, CSF biomarkers, MCI, OSA, beta-amyloid, tau