Sleep Changes in Dementia Over Time
Dementia affects how people sleep, and these changes get worse as the disease moves through its stages. In the early days, sleep problems might be mild, but they often grow into big issues that disrupt daily life.
Dementia covers several brain conditions like Alzheimer’s disease, vascular dementia, frontotemporal dementia, and Lewy body dementia. Sleep troubles show up in all types, but they change based on the stage of the illness. The stages include mild cognitive impairment or early changes, moderate dementia, and severe dementia.
In the beginning, during mild cognitive impairment or stage 3, people might have trouble falling asleep now and then. They could feel anxious about forgetting things, leading to restless nights. Forgetfulness and trouble focusing make it harder to wind down. Daytime sleepiness might start creeping in too.
As dementia reaches the moderate stage, like stage 4 or 6, sleep patterns really break down. People struggle to keep a normal sleep-wake cycle. They may sleep a lot during the day and stay awake at night. Sundowning is common here, where confusion ramps up in the late afternoon or evening, making bedtime tough. Wandering at night happens more, along with severe anxiety and mood swings that keep rest away.
In severe stages, sleep disturbances hit hard. Extreme confusion and personality changes mix with daytime sleepiness and changes in eating habits. People might not recognize loved ones or handle basic tasks, and poor sleep makes everything worse. In Lewy body dementia, alertness flips throughout the day, making steady sleep nearly impossible.
Science shows why these changes happen. In early Alzheimer’s, sleep spindles in the temporal lobe drop, speeding up cognitive decline. One bad night of sleep raises amyloid beta levels, a protein tied to Alzheimer’s, by 10 percent. A week of poor sleep boosts tau, another harmful protein linked to brain damage. Deep sleep, or slow wave activity, shrinks in Alzheimer’s patients, which ties to buildup of these proteins.
Disrupted sleep also hurts the brain’s cleanup process. During deep sleep, the brain clears waste like abnormal proteins. Conditions like sleep apnea, common in dementia, stop breathing at night and block this cleanup, raising dementia risk. Treating apnea might slow things down by improving oxygen flow and vessel health.
Even aging alone cuts deep sleep starting in the 30s, but dementia makes it worse. Kids get lots of deep sleep for growth, but adults lose it, waking easier from noises or shifts. New medicines like dual orexin receptor antagonists aim to fix this by boosting deep sleep and maybe slowing dementia.
These sleep shifts not only make dementia harder but also speed its progress. Spotting them early helps manage care.
Sources
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https://www.wellmedhealthcare.com/patients/healthyliving/conditions-diseases/what-are-the-stages-of-dementia/
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