Summary: Sleep apnea events during REM sleep are linked to verbal memory impairments in older adults at risk of developing Alzheimer’s disease. Research highlights the importance of focusing on the severity of sleep stage-specific apnea for accurate diagnosis and treatment.
Women were found to have more REM-related apnea events, potentially increasing their risk of Alzheimer’s disease. The study highlights the need for personalized sleep apnea assessments to combat cognitive decline.
Highlights:
- REM sleep apnea: Higher apnea events during REM sleep correlate with poorer verbal memory.
- Sexual differences: Women suffer more from REM sleep apnea, which potentially increases the risk of Alzheimer’s.
- Personalized treatment:Focusing on REM-specific apnea events is crucial for accurate diagnosis and treatment.
Source: University of California, Irvine
A research team led by the University of California, Irvine has revealed the link between the frequency of sleep apnea episodes during the rapid eye movement phase and the severity of verbal memory impairment in older adults at risk of developing Alzheimer’s disease.
Verbal memory refers to the cognitive ability to retain and recall information presented through spoken or written words and is particularly vulnerable to Alzheimer’s disease.
The study, recently published online in the journal Alzheimer’s disease research and therapy, discovered a specific correlation between the severity of sleep apnea – when breathing stops while an individual sleeps – and decreased cognition. Higher ratios during REM phases compared to non-REM phases were associated with poorer memory performance.
“Our results identified specific features of sleep apnea associated with memory, which is important because clinically, events occurring during REM sleep are often overlooked or downplayed,” said co-corresponding author Bryce Mander , associate professor of psychiatry and human sciences at UC Irvine. behavior.
“Most sleep hours are non-REM, so overall apnea severity averages may appear much lower than what is typically seen during REM sleep. This means that an at-risk individual may be misdiagnosed and undertreated because current assessment standards do not focus on the severity of sleep stage-specific apnea.
“Additionally,” said co-corresponding author Ruth Benca, professor and chair of psychiatry and behavioral medicine at Wake Forest University School of Medicine, “we found that women are more likely to have a greater proportion of their apneic events during REM sleep compared to men, which could potentially contribute to their greater risk of developing Alzheimer’s disease.
The study included 81 middle-aged and older adults from the Wisconsin Alzheimer’s Disease Research Center with increased risk factors, 62 percent of whom were women. Participants underwent polysomnography – a comprehensive test that records brain waves, eye movements, muscle activity, blood oxygen levels, heart rate and breathing during sleep – and memory assessments verbal.
Results showed that apnea episodes during REM sleep are a critical factor contributing to verbal memory decline, particularly in individuals with a genetic predisposition to Alzheimer’s disease and those with a parental history of Alzheimer’s disease. disease.
“Our findings highlight the complex relationship between sleep apnea, memory function and Alzheimer’s risk,” Mander said. “Identifying and treating REM-specific events is crucial to developing proactive, personalized assessment and treatment approaches tailored to individual sleep patterns. »
The team also included lead author Kitty K. Lui, a graduate student at San Diego State University/University of California, a joint doctoral program in clinical psychology in San Diego, as well as faculty and graduate students from UC Irvine, UC San Diego, Wisconsin Alzheimer’s Disease Research Center and University of Kentucky.
Funding: This work was supported by the National Institute on Aging under Grants R56 AG052698, R01 AG027161, R01 AG021155, ADRC P50 AG033514, R01 AG037639, and K01 AG068353; by National Institutes of Health Ruth L. Kirschstein National Research Service Award F31 AG048732; and by the Clinical and Translational Sciences Awards Program of the National Center for Advancing Translational Sciences under grant UL1TR000427.
About this research news on sleep apnea and memory
Author: Patricia Harriman
Source: University of California, Irvine
Contact: Patricia Harriman – UC Irvine
Picture: Image is credited to Neuroscience News
Original research: Free access.
“Older adults at higher risk of developing Alzheimer’s disease show stronger associations between REM sleep apnea severity and verbal memory” by Bryce Mander et al. Alzheimer’s disease research and therapy
Abstract
Older adults at higher risk of developing Alzheimer’s disease show stronger associations between REM sleep apnea severity and verbal memory
Background
Obstructive sleep apnea (OSA) increases the risk of cognitive decline and Alzheimer’s disease (AD). Although the underlying mechanisms remain unclear, hypoxemia during OSA has been implicated in cognitive impairment. OSA during rapid eye movement (REM) sleep is generally more severe than during non-rapid eye movement (NREM) sleep, but the relative effect of oxyhemoglobin desaturation during REM versus NREM sleep on memory is not completely characterized. Here, we examined the impact of OSA, as well as the moderating effects of AD risk factors, on verbal memory in a sample of middle-aged and older adults at increased risk for AD.
Methods
Eighty-one adults (mean age: 61.7 ± 6.0 years, 62% women, 32% Aallele of polipoprotein E ε4 (APOE4) carriers and 70% with parental history of AD) underwent clinical polysomnography including OSA assessment. OSA characteristics were derived from total sleep, NREM and REM. REM-NREM ratios of OSA features were also calculated. Verbal memory was assessed with the Rey Auditory Verbal Learning Test (RAVLT). Multiple regression models assessed relationships between OSA characteristics and RAVLT scores while adjusting for sex, age, time between assessments, years of education, body mass index (BMI ) And APOE4 status or parental history of AD. The significant main effects of OSA characteristics on RAVLT performance and the moderating effects of AD risk factors (i.e., gender, age, APOE4 status and parental history of AD) were examined.
Results
Apnea-hypopnea index (AHI), respiratory disturbance index (RDI), and oxyhemoglobin desaturation index (ODI) during REM sleep were negatively associated with RAVLT total learning and recall over a long period of time. Additionally, higher REM-NREM ratios of AHI, RDI, and ODI (i.e., more events in REM than in NREM) were related to poorer total learning and recall. We specifically found that the negative association between REM ODI and total learning was driven by adults aged 60 and older. Additionally, the negative relationships between REM-NREM ODI ratio and total learning, as well as REM-NREM RDI ratio and long-delay recall, were due to APOE4 carriers.
Conclusion
Greater severity of OSA, particularly during REM sleep, negatively affects verbal memory, particularly in individuals at higher risk of AD. These results highlight the potential importance of proactive screening and treatment of REM OSA, even if the overall AHI appears low.
News Source : neurosciencenews.com
Gn Health
