Sleep Disorders in Mild Cognitive Impairment.

We have an increasingly aging population and, therefore, cognitive impairment and dementia are becoming more common. Similarly, sleep disorders are also more common among the older population. There is a bidirectional relationship between mild cognitive impairment and sleep disorders. Additionally, both of these issues are underdiagnosed. By identifying and treating sleep disturbances early, we may delay the onset of dementia. Sleep helps in clearing metabolites like amyloid-beta (A-beta) lipoprotein. Clearance leads to decreased fatigue and proper functioning of the brain. A-beta lipoprotein and tau aggregates lead to neurodegeneration. Slow-wave sleep that decreases with aging is important for memory consolidation. In the initial stages of Alzheimer's disease, A-beta lipoprotein and tau deposits were linked to lower slow-wave activity in non-rapid eye movement sleep. Improvement in sleep decreases oxidative stress which in turn leads to decreased A-beta lipoprotein accumulation.