Sleep’s Important Role in Early Alzheimer’s Disease

Sleep’s Important Role in Early Alzheimer’s Disease

Sleep’s Important Role in Early Alzheimer’s Disease 1920 1280 Gary Ruelas, D.O., Ph.D.

A recent study delved into the connection between sleep patterns and cognitive function in individuals at risk of Alzheimer’s disease. Previous research has suggested that excessively short and long sleep durations might be associated with a higher risk of cognitive decline, but the precise link is still uncertain.

Researchers in this study found that addressing sleep disturbances to optimize sleep duration and enhance slow wave activity could potentially have a stabilizing effect on cognitive function in individuals in the preclinical or early symptomatic stages of Alzheimer’s disease.

Learn more about the study below:

“Sleep monitoring may provide markers for future Alzheimer’s disease; however, the relationship between sleep and cognitive function in preclinical and early symptomatic Alzheimer’s disease is not well understood. Multiple studies have associated short and long sleep times with future cognitive impairment. Since sleep and the risk of Alzheimer’s disease change with age, a greater understanding of how the relationship between sleep and cognition changes over time is needed. In this study, we hypothesized that longitudinal changes in cognitive function will have a non-linear relationship with total sleep time, time spent in non-REM and REM sleep, sleep efficiency and non-REM slow wave activity.

To test this hypothesis, we monitored sleep-wake activity over 4–6 nights in 100 participants who underwent standardized cognitive testing longitudinally, APOE genotyping, and measurement of Alzheimer’s disease biomarkers, total tau and amyloid-β42 in the CSF. To assess cognitive function, individuals completed a neuropsychological testing battery at each clinical visit that included the Free and Cued Selective Reminding test, the Logical Memory Delayed Recall assessment, the Digit Symbol Substitution test and the Mini-Mental State Examination. Performance on each of these four tests was Z-scored within the cohort and averaged to calculate a preclinical Alzheimer cognitive composite score. We estimated the effect of cross-sectional sleep parameters on longitudinal cognitive performance using generalized additive mixed effects models. Generalized additive models allow for non-parametric and non-linear model fitting and are simply generalized linear mixed effects models; however, the linear predictors are not constant values but rather a sum of spline fits. . .

Cognitive function was stable over time within a middle range of total sleep time, time in non-REM and REM sleep and <1 Hz slow wave activity, suggesting that certain levels of sleep are important for maintaining cognitive function.

Although longitudinal and interventional studies are needed, diagnosing and treating sleep disturbances to optimize sleep time and slow wave activity may have a stabilizing effect on cognition in preclinical or early symptomatic Alzheimer’s disease.”


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Gary Ruelas, D.O., Ph.D.

Dr. Ruelas holds doctoral degrees and is licensed to practice in both medicine and psychology. He approaches his patients by gathering and analyzing data differently from other physician’s moving away from a disease model to a holistic functional model. Read Bio

All articles by : Gary Ruelas, D.O., Ph.D.