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Most of us, especially if we are 60 or older, have a friend or loved one living with Alzheimer's. They may be in the early stages of the disease and still very functional. Or, they may already be in memory care and struggling to recognize family members. Watching someone you love change in this way is heartbreaking, and if you are in your 50s, 60s, 70s or beyond, it's only natural to worry about developing the disease yourself.
What causes Alzheimer's?
Alzheimer's is caused by an abnormal buildup of two proteins in the brain: amyloid and tau. Amyloid forms plaques around brain cells while tau causes tangles within the cells themselves. The damage begins years before symptoms develop. Over time, the buildup of these proteins starts to interfere with how neurons function. As neurons become damaged and die, brain tissue experiences inflammation and shrinkage.
Is it Alzheimer's, or just normal aging?
An estimated 6.7 million Americans aged 65 and older – roughly one in nine – are living with Alzheimer's. However, just because you lose your train of thought or can't recall why you went upstairs does not mean you should panic. Just as we slow down physically as we age, we also slow down mentally. Momentary lapses, such as losing a word here and there or forgetting the name of a favorite movie star don't necessarily mean you're developing Alzheimer's. Forgetting where you parked your car is normal, but forgetting how to drive or find your way home along familiar roads is not.
Understanding the Symptoms
Signs it could be Alzheimer's | Typical age-related changes |
---|---|
Memory loss that interferes with daily life. Forgetting recently learned information and asking the same questions repeatedly. | Occasionally forgetting names or appointments but remembering them later. |
Difficulty concentrating. Challenges making or carrying out a plan or working with numbers. | Making occasional errors while managing finances or paying household bills. |
Difficulty carrying out familiar tasks like making a grocery list or finding your way to the store. | Occasionally needing help to navigate the settings on your TV or new smartphone features. |
Losing track of days, dates or even seasons. Being confused about where you are and how you got there. | Forgetting the date or day of the week (easy to do if you are no longer working) but remembering or figuring it out. |
Trouble understanding visual images, such as road signs, gauging distance, and spatial relationships, or determining color and contrast. | Visual changes due to cataracts. |
Trouble following a conversation. Basic vocabulary issues. | Occasionally struggling to find a particular word. |
Misplacing things and not being able to retrace your footsteps to find them. Accusing others of moving or “stealing” something you have misplaced. | Misplacing something from time to time but retracing your footsteps to look for them. |
Poor judgment and decision making abilities and lapses in hygiene | Making an occasional mistake like forgetting to make an appointment or gas up the car. |
Withdrawal from work or social gatherings due to conversational difficulties | Not feeling like going out or attending a particular event on occasion. |
Moodiness. Personality changes such as easily becoming suspicious, anxious, or even angry. | Being used to doing things a certain way and getting annoyed when a routine is disrupted. |
Maybe it's not Alzheimer's
Because Alzheimer's disease is the most common form of dementia, people often use it as shorthand for any type of cognitive decline. However, there are a variety of conditions that cause similar symptoms:
- Cerebrovascular disease, or vascular dementia, is due to damage to blood vessels in the brain, which then deprives it of blood, oxygen, and nutrients.
- Frontotemporal degeneration (FTD) is a condition in which nerve cells in the front and temporal lobes of the brain soften and slowly die. The brains of people with FTD contain abnormal amounts or types of tau protein and another protein known as TDP-43. FTD usually occurs between the ages of 45 and 65 but can begin earlier.
- Hippocampal sclerosis (HS) is the shrinkage and hardening of tissue in the brain’s hippocampus, which plays a role in forming memories. People with HS have an accumulation of abnormal forms of TDP-43 protein.
- Lewy body disease (DLB) is caused by abnormal accumulations of the protein alpha-synuclein, in neurons in the cortex, the outermost layer of brain tissue. As these clusters, known as Lewy bodies, continue to form, dementia develops. Memory loss may be less pronounced than in Alzheimer's.
- Parkinson's disease (PD). As in Lewy Body disease, Parkinson's stems from abnormal amounts of the protein alpha-synuclein. However, these protein clumps tend to form deeper in the brain, in an area called the substantia nigra (as PD progresses, the clumps can form in the cortex as well). It is thought that the abnormal protein accumulations trigger a degeneration of the nerve cells that produce the neurotransmitter dopamine, which communicates chemical messages between nerve cells.
- Mixed etiology dementia. Sometimes, a person may develop more than one type of the brain changes described above. When these pathologies result in dementia symptoms, the person is said to have mixed etiology dementia.
Risk Factors for Alzheimer's
None of the risk factors listed below necessarily mean a person will develop Alzheimer's. However, their presence does indicate a higher risk of developing the disease:
- Age. Alzheimer's mostly strikes people who are 65 and older. After age 65, the risk of developing Alzheimer's doubles every five years. Twenty-two percent of adults 85-89 and 33 percent of adults ages 90 and older have been diagnosed with Alzheimer's.
- Gender. Women have a higher lifetime risk for Alzheimer's, but this could simply be because women live longer. According to the Center for Disease Control, US women had a life expectancy of 79 years in 2021, compared with 73 years for men.
- Family History and Genetics. Having a close family member with Alzheimer's, such as a parent or sibling, increases the risk of developing the disease. Several types of early dementias, such as Huntington's Disease, are linked to specific genes.
- Diabetes and insulin resistance. People with diabetes, especially type 2, have a higher risk of developing Alzheimer's and other forms of dementia.
- A history of head trauma. Studies show that a history of a serious head injury or repeated concussions increases the risk for developing Alzheimer's later in life.
- Heart disease. If the heart or blood vessels are damaged, this can impact blood circulation, reducing the amount of oxygen and nutrients that reach the brain.
Lowering Your Risk for Alzheimer's
Alzheimer's is a complex condition for which there is currently no cure. However, a variety of medications can be prescribed to address symptoms or slow the progression of the disease and more drugs are currently in the pipeline. Because Alzheimer's is such a common condition, it is heavily researched and medical science may yet find new approaches to treating it. In the meantime, there are things you can do to help reduce your risk:
- Exercise your brain. Studies suggest a strong link between mental stimulation and brain health. Choose leisure activities that make you think, as opposed to just plopping down in front of the TV. Solve puzzles. Play word games. Learn a new language or computer program. Join a book club. Take a class.
- Stay physically active. Regular exercise benefits brain health by increasing the flow of blood and oxygen to your brain.
- Nurture and maintain close relationships. Staying socially active and connected to friends and family may delay the onset of Alzheimer's.
- Watch your head! Wear a seatbelt while driving and a helmet while biking. Be careful going up and down ladders.
- Get regular check-ups. Identifying and managing chronic conditions such as heart disease, high blood pressure, or diabetes is essential to your physical and mental health.
If you are concerned about cognitive or memory issues, start by scheduling an appointment with your healthcare provider. They may refer you to a neurologist who will perform a physical exam to establish a baseline for your memory and cognition. Depending on the results of your evaluation, you may be referred to a neuropsychologist for further testing.
This article first appeared in the June 2023 edition of the HealthPerks newsletter.