Short sleep duration closely linked to dementia — poor sleep quality and sleep disorders negatively impact cognitive function
Lack of sleep impairs brain metabolism and waste clearance. Maintaining regular habits and a comfortable sleep environment is essential for dementia prevention.
If your memory seems weaker than usual as you age, it’s best not to jump to conclusions about dementia. Instead, get an accurate evaluation to distinguish between normal aging and pathological decline. Some level of cognitive slowdown is a natural part of aging.
According to medical experts, dementia is not a single disease but a state in which cognitive decline interferes with daily life. Studies of dementia patients consistently show common features such as poor sleep quality and sleep disorders, suggesting a strong connection between insufficient sleep and dementia onset.
Professor Jin-San Lee from Kyung Hee University Hospital’s Department of Neurology explained,
“Sleep deprivation is known to impair overall brain metabolism and waste removal processes, which can negatively affect cognitive function. In particular, disturbances in the metabolism of adenosine—a substance that accumulates while awake and promotes sleep—can occur. Moreover, metabolic by-products such as beta-amyloid, a key substance implicated in Alzheimer’s disease, may not be effectively cleared from the brain.”
In fact, a long-term study conducted in the UK in 2021 found that people who slept six hours or less per night had a 30% higher risk of developing dementia than those who slept seven hours or more. Sufficient sleep is therefore considered essential for maintaining brain health.
Good sleep means remaining asleep without frequent awakenings and reaching deep, restorative stages of rest where the brain can properly recover. Developing regular sleep habits and maintaining a quiet, comfortable environment are crucial for preventing dementia.
Dementia can generally be classified into degenerative dementia and vascular dementia.
More than 60% of cases are Alzheimer’s disease, the most common form of degenerative dementia, caused by the abnormal buildup of beta-amyloid and tau proteins in the brain. Symptoms—such as memory loss, language difficulties, spatial disorientation, and personality changes—progress slowly over many years.
By contrast, vascular dementia results from brain infarction or hemorrhage and appears suddenly, with symptoms like memory decline, personality changes, depression, and gait disturbance often worsening more rapidly than in degenerative dementia.
Professor Lee added,
“Aside from degenerative and vascular causes, dementia can also develop due to normal-pressure hydrocephalus, depression, or hypothyroidism. About 10% of dementia cases can improve if the underlying cause is properly treated. Therefore, if memory loss is suspected, it’s important to undergo neuropsychological and brain imaging tests to identify the exact cause.”
For example, dementia caused by normal-pressure hydrocephalus can improve when excess cerebrospinal fluid is drained. Similarly, cognitive decline resulting from hypothyroidism—where reduced metabolic activity leads to slower mental processes—can often be treated with thyroid hormone therapy.
Experts emphasize,
“There are roughly 70 different underlying conditions that can lead to dementia, and symptoms vary widely from patient to patient. Comprehensive observation that considers each person’s physical, psychological, and environmental factors is key to effective diagnosis and treatment.”
Source: Korea Town Dailiy (https://koreatowndaily.com)