Advanced age is associated with a decline in sleep duration and sleep quality. We are not certain to what extent aging causes sleep loss or to what extent sleep loss drives the aging process: both statements may be true to some extent.
Poor sleep quality appears to accelerate ageing at the cellular level: sleep loss is associated with shorter telomeres and possible increased cellular senescence, both of which are key mechanisms underlying the ageing process. Reduced sleep quality has been linked to increased risk of developing chronic diseases such as Alzheimer’s disease. Some evidence suggests sleep may play a role in clearing the brain of toxic proteins that drive neurodegenerative diseases.
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