Sleep Problems Can Be an Early Sign of Alzheimer’s

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Healthy people will occasionally experience sleep disturbances. However, disrupted sleep patterns can also serve as an early indicator of dementia, including Alzheimer’s disease, the most prevalent form of the condition. In fact, symptoms related to sleep irregularities can manifest years before an official diagnosis is made.

Neurodegenerative conditions like Alzheimer’s involve diminished responsiveness of brain cells to signaling chemicals, as well as the accumulation of excess waste material that hampers their normal functioning. As the disease progresses and brain cells deteriorate, specific regions of the brain may be lost.

A defining characteristic of Alzheimer’s is the buildup of specific proteins within the brain. These can disrupt efficient communication among various brain regions, including those responsible for regulating our circadian rhythm.

The primary controller of our sleep-wake patterns is the suprachiasmatic nucleus (SCN), located in the hypothalamus. The SCN coordinates our internal clock based on external cues such as light and darkness. It transmits signals to other brain regions to synchronize the body’s sleep-wake cycle accordingly.

Signs to Watch For

Getting enough sleep is vital for maintaining overall health, as insufficient sleep has been associated with a wide range of health concerns, including high blood pressure, diabetes, and obesity.

Research suggests that during sleep, the brain actively clears waste materials, and when sleep is insufficient, these substances can accumulate. Sleep also plays a crucial role in learning and memory consolidation. Disturbed sleep can impair these functions, leading to difficulties in these areas.

There are certain signs that individuals should be mindful of, including:

• Difficulty falling asleep.
• Frequent awakenings during the night.
• Evening agitation (sundowning).

A long list of symptoms has been associated with sleep deprivation, and these symptoms completely overlap with those of Alzheimer’s, Dr. Thomas Kilkenny, director of the Institute of Sleep Medicine at Northwell Staten Island University Hospital in New York told The Epoch Times.

“In both instances, the brain is not functioning properly, triggering the symptoms,” he said. “The difference being that in short-term sleep deprivation, when a good sleep is achieved, the symptoms will dissipate and the function is fully reversible,“ he added. ”In Alzheimer’s, this is not the case.”

Research demonstrated that sleep disturbances, particularly in middle age, significantly increase the risk of cognitive decline later in life.

A 2021 study revealed that individuals in their 50s and 60s who slept six hours or less were at a higher risk of developing dementia compared to those who slept around seven hours, with a 30 percent increased risk for the disorder.

A common and treatable sleep disorder, obstructive sleep apnea, affects over 25 percent of Americans and has been associated with cognitive decline.

Some of the signs of obstructive sleep apnea include:

• Loud and chronic snoring.
• Morning headaches.
• Daytime sleepiness.
• Dry mouth or sore throat.
• Irritability and mood changes.
• Memory problems.

Link Between Sleep Apnea and Loss of Brain Tissue

In a recent study published in the journal Neurology, researchers compared individuals who do not experience memory problems but exhibit amyloid plaques in the brain, protein formations recognized as the neuropathological hallmark of Alzheimer’s disease, to individuals who do not have amyloid plaques.

The findings revealed that those with amyloid plaques who also had more severe sleep apnea were more likely to exhibit lower volumes of brain matter in the medial temporal lobe, including the hippocampus, a region associated with memory and Alzheimer’s disease. The study does not establish a causal relationship between sleep apnea and reduced brain volume; rather, the researchers demonstrated an association.

Kilkenny added that the loss of neurons and their interconnections, referred to as cerebral atrophy, occurs in various brain structure-affecting conditions such as stroke, multiple sclerosis, and infections. “As these diseases progress, the brain loses more and more volume,“ he said. ”Cognitive ability declines and dementia sets in as the loss of brain volume continues.”

However, even in its early stages, Alzheimer’s disease can cause specific changes in brain chemistry that disrupt sleep patterns and hasten cognitive decline.

Alzheimer’s and Sleep: A Vicious Cycle

Research indicates that individuals in the early stages of Alzheimer’s disease may exhibit lower levels of melatonin, a hormone involved in regulating sleep, compared to those without the disease. The reduced production of melatonin is believed to stem from disrupted neuronal signaling between the suprachiasmatic nucleus and the pineal gland, which is responsible for melatonin secretion.

Neurodegeneration in the brain can also impact the areas that promote wakefulness and sleep. For instance, Alzheimer’s disease can impair the prefrontal cortex, which plays a role in decision-making and cognitive functioning. When this region is damaged, it can lead to sleep disturbances, such as difficulty falling asleep, staying asleep, and daytime drowsiness.

Can Melatonin Supplements Help?

There is evidence suggesting that melatonin supplements may be beneficial.

A systematic review of studies suggests that melatonin treatment for more than 12 weeks can effectively improve cognitive function in patients with Alzheimer’s. Furthermore, the review suggests that individuals with mild Alzheimer’s may derive greater benefits from melatonin use compared to those with moderate Alzheimer’s.

This is important because, past a certain point, the damage caused by sleep deprivation can become permanent and potentially contribute to the development of dementia.

Evidence also indicates that some cognitive capacities may remain impaired even after adequate sleep is restored, indicating that sleep loss can have long-term consequences on cognition.

“This suggests that frequent periods of sleep deprivation may trigger a permanent cognitive decline leading to dementia,” Kilkenny said. “Maintenance of adequate sleep time and sleep quality is therefore vital in maintaining peak cognitive performance.”