In Frontiers in neurology
OBJECTIVES : Obstructive sleep apnea (OSA) may increase the risk of Alzheimer's disease (AD). However, potential associations among sleep-disordered breathing, hypoxia, and OSA-induced arousal responses should be investigated. This study determined differences in sleep parameters and investigated the relationship between such parameters and the risk of AD.
METHODS : Patients with suspected OSA were recruited and underwent in-lab polysomnography (PSG). Subsequently, blood samples were collected from participants. Patients' plasma levels of total tau (T-Tau) and amyloid beta-peptide 42 (Aβ42) were measured using an ultrasensitive immunomagnetic reduction assay. Next, the participants were categorized into low- and high-risk groups on the basis of the computed product (Aβ42 × T-Tau, the cutoff for AD risk). PSG parameters were analyzed and compared.
RESULTS : We included 36 patients in this study, of whom 18 and 18 were assigned to the low- and high-risk groups, respectively. The average apnea-hypopnea index (AHI), apnea, hypopnea index [during rapid eye movement (REM) and non-REM (NREM) sleep], and oxygen desaturation index (≥3%, ODI-3%) values of the high-risk group were significantly higher than those of the low-risk group. Similarly, the mean arousal index and respiratory arousal index (R-ArI) of the high-risk group were significantly higher than those of the low-risk group. Sleep-disordered breathing indices, oxygen desaturation, and arousal responses were significantly associated with an increased risk of AD. Positive associations were observed among the AHI, ODI-3%, R-ArI, and computed product.
CONCLUSIONS : Recurrent sleep-disordered breathing, intermittent hypoxia, and arousal responses, including those occurring during the NREM stage, were associated with AD risk. However, a longitudinal study should be conducted to investigate the causal relationships among these factors.
Tsai Cheng-Yu, Wu Sheng-Ming, Kuan Yi-Chun, Lin Yin-Tzu, Hsu Chia-Rung, Hsu Wen-Hua, Liu Yi-Shin, Majumdar Arnab, Stettler Marc, Yang Chien-Ming, Lee Kang-Yun, Wu Dean, Lee Hsin-Chien, Wu Cheng-Jung, Kang Jiunn-Horng, Liu Wen-Te
2022
“Alzheimers disease”, amyloid beta-peptide 42, arousal response, obstructive sleep apnea, sleep-disordered breathing, total tau
