Alzheimer’s Disease: When the Brain Stops Functioning

Gut Related Approaches Bring Hope

Hands holding a purple ribbon with the word "Hope"

We forget why we come into a room. We want to introduce a neighbor we’ve known for years—and forget her name. We search for a common word that remains elusive. If we are over 50, we start worrying. Are these the ordinary signs of an aging brain or are these symptoms of Alzheimer’s disease?

For most of us, occasionally experiencing these symptoms are a part of normal aging. However, if symptoms increase and worsen, the fear of developing Alzheimer’s is not unfounded, especially for women who are at significantly higher risk.

According to Alzheimer Association statistics, about 5.5 million American have AD—and one in three seniors will die of the disease. About two-thirds of Americans with Alzheimer’s disease (AD) are women, while African Americans are also at higher risk.

CDC infographic showing which races are at higher risk of getting Alzheimer's disease

Percentage of Adults Aged 65 and Older with Alzheimer’s Disease by Race and Ethnicity according to CDC statistics:

  • 14% African Americans
  • 12% Hispanics
  • 10% Non-Hispanic Whites

While death from other major illnesses have declined in recent years, Alzheimer deaths more than doubled. Between 2000 and 2017, death from heart disease decreased 9%, while death from Alzheimer’s disease increased 145%.

While about 5 million people developed AD in 2014, this number is expected to triple by 2060, with 14 million people who are projected to have the disease. It is the fifth leading cause of death among those over 65 (and the sixth leading overall cause of death in the U.S.). More people die from Alzheimer’s than from breast and prostate cancer combined.

Most physicians consider Alzheimer’s incurable, although two types of drugs are commonly prescribed to improve cognitive skills or slow the progress of the disease. The Mayo Clinic website describes improvements with these drugs “modest.” Since the disease is progressive, any benefits may only help for a time.

New drugs are in development, but researchers are also exploring the link between brain health and heart and blood vessel health. According to the Mayo Clinic, “The risk of developing Alzheimer’s appears to increase as a result of many conditions that damage the heart or arteries. These include high blood pressure, heart disease, stroke, diabetes and high cholesterol.” To reduce risk, researchers are exploring everything from blood pressure medications to changes in diet.

“We already know that a diet rich in prebiotic fiber can reduce disease risk. Most Americans don’t get enough fiber from food. Daily supplementation with Prebiotin has been shown to improve the gut microbiome and reduce the risk of major illnesses like heart disease, stroke, diabetes, and depression, ” says F. Wilson Jackson, MD, Medical Director for Prebiotin.

“With the growing body of research that now links specific gut microbiota and the onset and progress of AD, we are excited that Prebiotin’s documented impact on improving gut health may also provide a therapeutic benefit for individuals with Alzheimer’s disease.”

What are the symptoms of Alzheimer's disease?

image of older lady, lost and alone

Symptoms that mark the onset of the disease often appear at age 65 or older (although a minority of people develop symptoms earlier). Actual changes in the brain related to AD can begin 20 years before symptoms become visible. Progression with the disease can be slow and uncertain.

Some individuals with Alzheimer’s disease survive only 4 to 8 years. Others survive 20 years after disease onset.

The Alzheimer’s Association categorizes symptoms into three stages:

Mild stage: increased difficulty doing ordinary tasks: Mild cognitive impairment (MCI) can be a symptom of early Alzheimer’s disease. Someone may forget what they just read, regularly forget where they place valuable objects, and have increasing difficulty doing ordinary tasks, from planning dinner to completing tasks at work

However, at this stage diagnosis may be tricky. In a review article on the public health impact of AD, scientists found about 15-20% of all individuals over 65 have some mild cognitive impairment from a range of other causes. These causes can include stroke, traumatic brain injury, medication side effects, vitamin B12 deficiency, and depression. About 32% of all individuals with mild cognitive impairment developed Alzheimer’s disease within the 5-year follow-up.

Moderate stage: changes in personality and confusion. The individual may have greater difficulty performing simple tasks like paying bills or even remembering their phone number or address. He or she may become frustrated or angry and confuse words. Some may begin to wear inappropriate clothing or start avoiding social events they used to enjoyed. People often have changes in sleep patterns and may start wandering at night. This phase often lasts the longest.

Severe stage: losing touch with one’s surroundings. In the final stage of the disease, symptoms are severe. Some no longer recognize loved ones and lose their ability to carry on a conversation or control their movements. Eventually, the individual may be unable to walk at all, have difficulty eating and swallowing, and require full-time help with personal care. At this stage, infections, especially pneumonia, are common.

Economic and Social Impact of Alzheimer’s Disease

According to the Alzheimer’s Association, in 2019, Alzheimer’s and other dementias will cost the nation $290 billion, including $195 billion in Medicare and Medicaid payments.

By 2050, these costs could rise as high as $1.1 trillion. This dramatic rise includes more than four-fold increases both in government spending under Medicare and Medicaid and in out-of-pocket spending.

The approximate lifetime cost of care for an individual living with dementia is $350,174 (with 2018 costs).

image of child helping elderly lady with Alzheimer's disease

Medicare beneficiaries with Alzheimer’s or other dementias are more likely to have other chronic conditions like heart disease, diabetes, and kidney disease.

The Cost to Families

Families bear about 70% of the total lifetime cost of caring for someone with dementia. Alzheimer’s takes a devastating toll on caregivers (often daughters). Compared to caregivers of individuals without dementia, those who care for people with dementia are twice as likely to experience substantial emotional, financial, and physical difficulties.

Diagnosis and Treatment

Despite the rapid growth of people living with Alzheimer’s disease, only around one in four get diagnosed.

Diagnosing Alzheimer’s disease is often done by a neurologist (brain specialist) or geriatrician (a specialist in treating older adults). During the appointment, the doctor evaluates the patient’s cognitive skills.

Other conditions that may cause symptoms, from medication reactions, to strokes, depression, or Parkinson’s disease, are ruled out.

Sometimes the doctor also talks to friends and family members to get a more complete picture of any changes in brain function. He or she may also order additional lab tests, brain-imaging, or neuropsychological tests to evaluate memory and cognitive skills.

Between 2000 and 2017, death from heart disease decreased 9%, while death from Alzheimer’s disease increased 145%.

 Alzheimer’s Association

Common brain-imaging technologies include:

  • Magnetic resonance imaging (MRI) using powerful radio waves and magnets to create a detailed view of the brain.
  • Computerized tomography (CT) using X-rays to obtain cross-sectional images of the brain.
  • Positron emission tomography (PET) using a radioactive substance known as a tracer to detect specific substances in the body associated with different types of degenerative brain disease.

According to the Mayo Clinic, PET scans have recently been developed that detect clusters of amyloid proteins (plaques), which are associated with Alzheimer’s dementia.

Dementia and Alzheimer’s Disease: What’s the Difference?
Dementia is the general term that describes symptoms that affect memory, communication abilities, and the performance of daily activities. About 50-70% of dementia is the result of Alzheimer’s disease. Huntington’s and Parkinson’s disease can also cause dementia but affect different brain cells.

 

How the Brain Changes with Alzheimer’s Disease

NIH’s National Institute on Aging tells us that healthy human brain contains tens of billions of neurons. These specialized cells process and transmit information via electrical and chemical signals. The neurons send messages between different parts of the brain and from the brain to other parts of the body.

With Alzheimer’s disease, normal communication is disrupted among the neurons. This results in cell death and loss of brain function.

The following are the main changes in the brain as the disease develops:

  • Hard, insoluble accumulations of beta amyloid proteins, or amyloid plaques, clump together between the nerve cells (neurons). In a healthy brain these protein fragments are broken down and eliminated. With Alzheimer’s, the amyloid plaques eventually cause the death of the cell.
  • Abnormal accumulations of a protein called tau, also called neurofibrillary tangles, collect inside neurons. These tangles block the neuron’s transport system, harming the synaptic communication between neurons, also eventually killing the cell.
  • Microglia, a type of glial cell which surrounds neurons to provide support and insulation, fail to perform their vital function of clearing away waste, debris, and protein collections, including beta-amyloid plaques.
  • As a result, chronic inflammation sets in, causing cell loss. Normal brain function is further compromised by the decreased ability of the brain to metabolize glucose, its main fuel.
  • Reduced blood flow and oxygen to the brain from vascular problems that affect blood vessels is also linked to Alzheimer’s disease.

These changes cause connections between networks of neurons to break down as neurons are damaged and die throughout the brain. As a result, many brain regions begin to shrink or atrophy. By the final stages of Alzheimer’s, this process is widespread, with significant loss of brain volume.

Image of a brain, healthy side is full and plump, the Alzheimer's side is smaller with gaping areas where the brain has atrophied

AD Damages the Brain

In early stages, these brain changes result in subtle declines in cognitive function. As plaques and tangles spread and damage more nerve cells, the individual with Alzheimer’s disease shows significant cognitive decline and personality changes.

In later stages, basic bodily functions like swallowing and movement are impaired.

Is there hope for new treatments?

Currently, there are no cures yet for this devastating disease. The U.S. Food and Drug Administration (FDA) has approved six prescription medicines that treat symptoms or slow the progress of the disease. However, as the disease progresses, medications become less effective.

Researchers continue to investigate experimental treatments to modify the disease process itself in the quest to find a cure. Finding biomarkers to identify individuals in the early stages of the disease is another focus for research. Treatment for Alzheimer’s disease is most effective before the brain sustains extensive damage.

image of older man stimulating his brain with cognitive activities

Some studies demonstrate the benefits of cognitive stimulation (games and activities that stimulate the brain) and exercise to slow cognitive decline. A recent study notes that early retirement is linked with more rapid cognitive decline. Other research focuses on the importance of social interactions to stop or delay cognitive decline.

The impact of lifestyle is the subject of a CDC blog, Alzheimer’s Disease-Genes Do Not Equal Destiny. The blog focuses on the results of two long-term studies. Lifestyle changes can help even those who have increased genetic risk:

  • Exercise
  • A healthy diet
  • Less alcohol consumption
  • No smoking

A September 2019 article in NeuroscienceNews.com makes the intriguing observation that lifelong supplementation with the common nutrient choline may help to combat inflammation in the brain and block the production of amyloid plaques.

Another approach may be to conduct a saliva test of amyloid-β42 (Aβ42) levels at least a decade prior to the typical onset of AD (65). If the test indicates that Aβ42 levels are elevated, researchers indicate that taking anti-inflammatory drugs like NSAIDS may help prevent the disease. Researchers are now looking for the correct levels of the drugs to prevent AD.

The Link between Cognition and the Gut Microbiome

A major focus of Alzheimer’s research is the gut-brain axis—the impact of the gut microbiome on the central nervous system function.

Infographic showing the Gut-Brain Axis

Researchers have found that people with the disease have more undesirable bacteria in their gut microbiome (the collection of bacteria, viruses, fungi, and other microbes that live in your gut), with less abundant amounts of desirable bacteria like Bifidobacteria.

The authors of “Gut microbiome alterations in Alzheimer’s disease,” add AD to the growing list of diseases associated with gut microbial alterations. The findings from the 2017 article in Nature “suggest that gut bacterial communities may be a target for therapeutic intervention.”

Another study also finds a “distinctly different composition of bacteria” in AD patients. The researchers conclude that alterations in gut microbial communities in AD patients may result in brain changes. They note that an abundance of Bacterioides (a type of bacteria) may cause inflammation that contributes to AD pathology.

A growing body of research supports this link between gut composition and brain inflammation. Scientists link intestinal microbiota to the inflammation found in various neurological conditions, including autism spectrum disorders, multiple sclerosis, Parkinson’s disease, and AD in a July 2019 article in the Journal of Experimental Medicine.

Authors of a September 2019 article in Smithsonian Magazine succinctly sum up these findings: “The microbes in the gastrointestinal tract influence the immune system and the brain, possibly playing a role in the development of Alzheimer’s.”

Decreasing Inflammation with Prebiotin

The next stage of clinical research is focusing on how supplementation with prebiotics and probiotics can improve cognitive, sensory, and emotional functions in people with AD.

In a 2017 study where rats receive Lactobaccillus bacteria strains, scientists note positive results on the progression of AD.

Similarly, authors of a 2018 study with mice who were fed prebiotic inulin note that supplements can create a healthy microbiome. These supplements “could be effective in counteracting the onset of AD.”

Because Prebiotin is a known product in the scientific community, researchers who are investigating ways to impact gut health to improve brain function and other health conditions often select Prebiotin.

“We are incredibly excited to collaborate with prestigious medical centers such as the University of Maryland, Columbia University, and the University of Pittsburgh as they study the “gut to brain connection,” says Greg Cooper, Prebiotin Director of Product and Business Development.

“Recent findings indicating the benefits of Prebiotin® Prebiotic Fiber have led to millions of dollars in grants from the NIH to further study the relation our gut microbiome has with diseases that affect cognition and other chronic health concerns.”

Dr. Jackson concludes, “By keeping the gut healthy, Prebiotin may play an important role in helping to combat Alzheimer’s disease.”

“Scientists have already determined that a wide range of lifestyle factors—from fiber-rich, heart healthy diets and exercise to social engagement and stress reduction—can impact gut health and reduce disease risk.

Although we are facing an increase in Alzheimer’s disease as our population ages, a growing body of research is finetuning the link between specific gut bacteria and the prevention of AD symptoms. This can give us tremendous hope.”

Image of healthy, happy, functional woman of advanced years

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