Sleep and its influence on Alzheimer's Disease
October 2020
What is Alzheimer’s disease?
Alzheimer’s disease is a progressive disease that causes brain cells to waste
away and die. It is a type of dementia that affects memory, thinking and behavior. Symptoms eventually grow severe enough to interfere with daily tasks. Alzheimer's is the most common cause of dementia, a general term for
memory loss and other cognitive abilities serious enough to interfere
with daily life. Alzheimer's disease accounts for 60-80% of dementia
cases and is not a normal part of aging.
What are the symptoms of Alzheimer's disease?
The most common early symptom is difficulty remembering new information. Our brains change as we age, and some slowed thinking and occasional problems with remembering certain things can happen. However, serious memory loss, confusion, and other major changes may be indicative of a dementia-related illness. The person experiencing symptoms may not notice the changes occurring. Signs of dementia may be more apparent to family or friends.
What are the risk factors for Alzheimer’s?
Scientists believe that a combination of genetic, lifestyle, and environmental factors that affect the brain over time causes Alzheimer’s. According to the Mayo Clinic, less than 1% of the time, Alzheimer’s is caused by specific genetic changes that guarantee a person will develop the disease with onset in middle age.
• Age – Increasing age is the greatest risk factor. While Alzheimer’s is not a normal part of aging, your likelihood for developing Alzheimer’s increases as you age.
• Family history and genetics – If you have a first-degree relative, like a parent or sibling, with Alzheimer’s, your chance of developing the disease is higher. A certain genetic factor, a variation of apolipoprotein E gene (APOE e4), increases the risk of Alzheimer’s disease but is not a guarantee that people with this gene will develop the disease.
• Down Syndrome – Many people with Down syndrome develop Alzheimer’s disease. This could be a result of having 3 copies of chromosome 21, which is the gene responsible for the creation of beta-amyloid. Signs and symptoms also appear 10-20 years earlier in people with Down syndrome.
• Sex – There appears to be little difference in risk between men and women, but more women have the disease possibly because they live longer than men.
What are the 10 signs of Alzheimer's disease?
1) Memory loss that disrupts daily life
One of the most common signs of Alzheimer's disease, especially in the early stage, is forgetting recently learned information. Others include forgetting important dates or events, asking for the same questions over and over, and increasingly needing to rely on memory aids (e.g., reminder notes or electronic devices) or family members for things they used to handle on their own.
Typical age-related change: sometimes forgetting names or appointments, but remembering them later.
2) Challenges in planning or solving problems
Some people may experience changes in their ability to develop and follow a plan or work with numbers. They may have problems following a familiar recipe or keeping track of monthly bills.
Typical age-related change: making an occasional error when managing their finances or bills.
3) Difficulty completing familiar tasks
People with Alzheimer’s often find difficulties completing daily tasks. They may have problems finding a familiar location or organizing a grocery list.
Typical age-related change: needing help with microwave settings or recording a TV show.
4) Confusion with time or place
People living with Alzheimer's can lose track of dates, seasons and the passage of time. They may have trouble understanding something if it is not happening immediately. Sometimes they may forget where they are or how they got there.
Typical age-related change: getting confused about the day of the week but figuring it out later
5) Trouble understanding visual images and spatial relationships
Some people with Alzheimer’s may experience vision problems. This can lead to issues with balance or reading. It can also cause problems with depth perception and driving.
Typical age-related change: vision changes due to cataracts.
6) New problems with words in speaking or writing
People with Alzheimer’s may have trouble following or joining in on a conversation. They may stop in the middle of a conversation and have no idea how to continue or they may repeat themselves. They may struggle with vocabulary, have trouble naming a familiar object or use the wrong name.
Typical age-related change: sometimes having trouble finding the right word.
7) Misplacing things and losing the ability to retrace steps
A person with Alzheimer’s may put things in unusual places. They may lose things and be unable to go back over their steps to find them again. As the disease progresses, they may begin to accuse others of stealing.
Typical age-related change: misplacing items occasionally but being able to retrace steps to find them.
8) Decreased or poor judgment
Individuals may experience changes in judgment or decision-making. For example, they may use poor judgment when dealing with money or pay less attention to grooming or keeping themselves clean.
Typical age-related change: Making a bad decision or mistake once in while like neglecting to change the oil in their car.
9) Withdrawal from work or social activities
A person with Alzheimer’s may have trouble following or carrying on a conversation. This can cause them to withdraw from hobbies, social activities, or other engagements.
Typical age-related change: sometimes feeling uninterested in family or social obligations.
10) Changes in mood or personality
Mood and personality changes can occur in a person living with Alzheimer’s. They can become confused, suspicious, depressed, fearful or anxious. They may be easily upset at home, with friends, or when they are out of their comfort zone.
Typical age-related change: Having a specific way of doing something and becoming irritable when a routine is disrupted.
How does Alzheimer’s affect the brain?
The brain is the most powerful organ in the body weighing in around 3 lbs. It is composed of 3 parts:
The Cerebrum
This is the largest part of the brain. It fills up most of the skull. It is involved in remembering, problem solving, thinking, and feeling. It also controls movement.
The Cerebellum
It sits at the back of your
head under the cerebrum. It controls coordination and balance.
The Brain Stem
It sits beneath the cerebrum in front of the cerebellum. It connects the brain to the spinal cord and controls automatic functions like breathing, digestion, heart rate, and blood pressure.
Alzheimer’s disease leads to nerve cell death and tissue loss throughout the brain. Over time, the brain will shrink dramatically and lose nearly all of its function.
A brain without the disease.
A brain with advanced Alzheimer's.
Comparison of the 2 brains.
Alzheimer’s causes a buildup of plaques and tangles within the brain. Plaques are abnormal clusters of protein fragments that build up between nerve cells. Plaques
form when protein pieces called beta-amyloid clump together. Beta-amyloid comes from a larger protein found in the fatty membrane surrounding nerve cells. When
beta-amyloid clumps together, this can prevent cell to cell signaling between nerve cells. Tangles are made up of twisted strands of proteins that occur in dead and
dying nerve cells. These tangles destroy a vital cell transport system, which keeps nutrients and essential nutrients from moving through cells. As the disease progresses, these plaques and tangles spread throughout the brain in a predictable pattern.
What are the stages of Alzheimer’s?
Alzheimer’s disease typically progresses slowly in three stages: early (mild), middle (moderate), and late (severe). Everyone progresses differently through the stages, and the rate of progression is unique to each person. According to the Alzheimer’s Association, on average, a person lives 4-8 years after diagnosis but can live as long as 20 years. Unfortunately, changes in the brain begin years before any signs or symptoms appear. This phase is known as preclinical Alzheimer’s.
Early stage Alzheimer's (Mild)
In this stage, a person may be functioning independently still. They may still drive, engage in social activities, or work. However, a person may feel as if they are having memory lapses, such as forgetting familiar words. Symptoms may not be widely apparent, but friends and family may begin to notice.
Common difficulties:
• Coming up with the right word or name
• Remembering names when they are introduced to new people
• Difficulty performing tasks in social or work settings
• Forgetting material that was just read
• Losing or misplacing a valuable object
• Experiencing increased trouble with planning or organizing
During the early stage, people with dementia can still lead a meaningful life. This is the ideal time to put legal, financial, and end-of-life plans together while they can still participate in the decision making process.
Middle-stage Alzheimer's (Moderate)
This stage is typically the longest and can last for many years. As the stage and disease progress, the person with Alzheimer’s will require larger amounts of care. Symptoms will become more pronounced, the person may confuse words, get frustrated or angry, and act in unexpected ways, such as refusing to bathe or shower. As nerve cells become more damaged in this stage, it may be difficult for the person to express their thoughts or perform routine tasks without help.
Symptoms of this stage include:
• Being forgetful of events and personal history
• Feeling moody and withdrawn, especially in socially or mentally challenging situations
• Inability to recall information about their themselves like their address or phone number
• Experiencing confusion about where they are or what day it is
• Requiring help choosing proper clothing for the season or occasion
• Trouble controlling bladder or bowels
• Changes in sleep patterns
• Increased tendency to wander and become lost
• Demonstrating personality and behavioral changes, including auspiciousness, delusions, or compulsive, repetitive behavior like hand-wringing or tissue shredding
During this stage, the person living with Alzheimer’s can still participate in daily activities with assistance. Find out what they can still do or a way to simplify tasks. As the need for care intensifies, caregivers may need respite care or an adult day center.
Late-stage Alzheimer’s (Severe)
In this stage, the symptoms of dementia are most severe. Individuals will lose their ability to respond to their environment, to carry on conversation, and, eventually, to control movement. They may still say some words or phrases, but communicating any pain they may be experiencing is difficult. As memory and cognitive skills continue to worsen, significant personality changes may occur, and individuals will need extensive care.
Complications in this stage include:
• Require round the clock assistance with daily personal care
• Lose awareness of recent experiences as well as their surroundings
• Changes in physical abilities, including walking, sitting, and eventually swallowing
• Difficulty communicating
• Vulnerable to infections, especially pneumonia
Initiating engagement may be difficult for individuals in this stage, but they can still benefit from appropriate activities like listening to relaxing music or receiving reassurance through gentle touch. Hospice care can be very beneficial for caregivers and their loved ones.
How does sleep affect the risk of developing Alzheimer’s?
During deep, restorative sleep, the brain “washes itself.” It needs this time to get rid of the resulting debris from normal neurological damage that occurs throughout the day. Without sleep, our brains can not wash away the accumulation of beta-amyloid. In a study conducted by the National Institutes of Health, researchers found that after just 1 night of lost sleep that the participants had 5% more beta-amyloid in their brain than the participants that had a full night’s rest.
New research at UC Berkeley has found that a defense against Alzheimer’s disease is to get that deep, restorative sleep. They also believe that they can estimate, with some degree of accuracy, when Alzheimer’s will occur in a person’s lifetime. Instead of waiting for dementia to occur, our sleep patterns and quality can be used to assess our risk. This information can be used by doctors to assess sleep quality and use sleep as a prevention strategy. For more information on how to get better sleep, click here.
Sources:
https://www.alz.org/alzheimers-dementia/what-is-alzheimers
https://www.alz.org/alzheimers-dementia/difference-between-dementia-and-alzheimer-s
https://www.alz.org/alzheimers-dementia/stages
https://www.mayoclinic.org/diseases-conditions/alzheimers-disease/symptoms-causes/syc-20350447
https://www.nih.gov/news-events/nih-research-matters/sleep-deprivation-increases-alzheimers-protein