Progress in studies of the reciprocal interaction between sleep disorders and Alzheimer's disease

Alzheimer's disease (AD) is a common neurodegenerative disease in the elderly, and is the most common cause of dementia. Epidemiological studies have discovered that, 44% of patients with AD are associated with sleep disorders and (or) circadian rhythm disorders. Now there are growing evidences indicating that interstitial fluid amyloid-β protein (A β) levels exhibit circadian rhythm fluctuation, and sleep disorders will accelerate the process of Aβ deposition, which may act as a risk factor of AD, suggesting the possible reciprocal interaction between sleep disorders and AD. The mechanism is not yet completely clear. Sleep disorders may be related with the impairments of both sleep-wake regulating system, circadian rhythm regulating system and the change of zeitgeber in AD. Sleep disorders would affect neuronal activity, neurotransmitter secretion, and as a stressor affecting A β processing and metabolism, thus accelerate the pathological process of AD. This paper reviewed the progress in the studies of reciprocal interaction between sleep disorders and Alzheimer's disease and the possible mechanisms.