What Is Alzheimer’s Disease?

Deterioration in cognitive capacities including thinking, memory, language, judgment, and learning are hallmarks of Alzheimer’s disease (AD), a degenerative brain disorder. The National Institute on Aging (NIA) reports that there is currently no cure for Alzheimer’s disease, but that certain medicines may help with symptom management.

Alzheimer’s disease often strikes adults over the age of 65 (in more than 90% of cases). A research published in Alzheimer’s & Dementia in March 2021 estimated that 6.2% of the 65+ population in the United States were living with Alzheimer’s disease that year. Without a medical breakthrough, the illness might affect 13.8 million Americans by 2060, when the population is expected to have increased further. Knowing the symptoms, causes, and potential dangers of Alzheimer’s disease is crucial.

Why Do We Have Alzheimer’s?

Alzheimer’s disease is often misdiagnosed as dementia and vice versa. The National Institute on Aging (NIA) defines dementia as "persistent and severe cognitive impairment that causes significant distress or impairment in daily life." This includes difficulties with thinking, remembering, and reasoning. Alzheimer’s disease is the most typical cause of dementia and is associated with permanent brain abnormalities. According to a report published in Nature Reviews Disease Primers in May 2021, 60-90% of patients with dementia have Alzheimer’s disease.

Natural cognitive changes are possible as people age. On rare occasions, people may experience memory lapses, misplace items, or struggle to express themselves adequately. Memory, learning, judgment, and personality are all affected in people with Alzheimer’s disease. The March 2021 report states that these symptoms are disruptive to daily life. According to the National Institute on Aging (NIA), persons with Alzheimer’s may experience hallucinations and a loss of ability to care for oneself as the illness develops.

Alzheimer’s disease can manifest in either an early or a late onset form. Early-onset Alzheimer’s disease often affects people in their 30s to mid-60s. According to the NIA, this only accounts for around 10% of all instances of Alzheimer’s. The typical onset age for late-onset Alzheimer’s disease is the mid-60s. According to StatPearls, the average lifespan of a person with late-onset Alzheimer’s disease is 4-8 years, however this can be as high as 20 years in certain cases. According to the NIA, the delay between diagnosis and death increases with patient age.

Mild cognitive impairment (MCI) is a kind of dementia that can be caused by Alzheimer’s disease but often only impairs one or two cognitive functions (such as memory) and does not cause significant functional impairment. Temporary factors like medicine, alcohol, or a head injury can trigger MCI without causing it to proceed to dementia. According to Alzheimers.gov, there is hope for certain patients. According to the study published in May 2021, Alzheimer’s causes around 50% of instances of MCI.

Causes

Because it affects the brain’s nerve cells (neurons), Alzheimer’s is classified as a neurodegenerative disorder. The shrinking and inflammation of the brain are brought on by changes in neurons and the loss of connections between them. The March 2021 article indicates that this process can begin long before any symptoms appear.

Amyloid plaques and tau tangles were once thought to be the primary biological brain alterations in understanding Alzheimer’s disease. Outside of neurons, amyloid plaques (clumps of poisonous beta-amyloid 42 protein) accumulate. Naturally occurring beta-amyloid 42 is elevated to pathological levels in Alzheimer’s disease. Inside neurons, tau tangles develop when tau molecules clump together in an unnatural way.

According to the NIA, neuronal microtubules (structures that give form to and route nutrients through the neuron) are typically stabilized by tau molecules. However, a July 2022 study suggested that the significance of beta-amyloid proteins as a main predictor of Alzheimer’s disease may have been exaggerated due to the use of faked research data.

Researchers into Alzheimer’s disease continue to hold that beta-amyloid proteins are crucial to our knowledge of the illness. However, this discovery may prompt researchers to investigate alternative protein models.

According to the NIA, the causes and consequences of these metabolic alterations on mental capacity remain unknown. Some genetic, environmental, and behavioral risk factors have been identified, but there is currently no method to predict how they will impact an individual or implement effective preventative measures.

Risk Factors

Age is the single most important risk factor for developing Alzheimer’s disease, accounting for more than 90% of all cases in those aged 65 and over. According to StatPearls, roughly 10% of persons over 65 and about 40% of those over 85 have Alzheimer’s disease. Additional danger causes can be:

• Having a family history of Alzheimer’s might put you at a higher risk of developing the disease yourself. According to the NIA, the predominant cause of Alzheimer’s disease in younger adults is genetics.
• NIA classifies hypertension, coronary heart disease, and stroke as vascular (blood vessel) disorders. The March 2021 research states that the brain consumes 20% of the body’s oxygen supply, making a strong heart crucial to the proper functioning of the brain. Regular exercise and a heart-healthy diet are two ways to lower your chance of developing cardiovascular disease.
• Risk factors, according to the May 2021 research, include metabolic disorders including diabetes, obesity in middle age, and low HDL cholesterol ("good" cholesterol). In order to convert the nutrients in meals into usable energy, your body uses a process called metabolism.
• According to a paper published in the journal Lancet Commissions in July 2020, depression can raise the risk of Alzheimer’s. There is some evidence that antidepressant medication lowers risk, although it is inconclusive. Dementia and the first stages of Alzheimer’s disease share several symptoms with depression.
• The NIA found that illnesses including high blood pressure, heart disease, and depression, as well as social isolation and loneliness, were all associated with an increased chance of developing Alzheimer’s disease. On the other hand, studies suggest that engaging in more group activities might boost brain power.
• According to research published in the journal Lancet Psychiatry in April 2018, having a history of traumatic brain injury (TBI) increases the likelihood of developing Alzheimer’s disease.
• Changes in the brain and cognitive problems, such as dementia, are linked to chronic heavy alcohol consumption. According to a report published in Alzheimer’s Research & Therapy in January 2019, it is still unknown if alcohol usage might promote Alzheimer’s disease.
• According to research published in Annals of Clinical and Translational Neurology in September 2018, smoking raises risk but quitting lowers risk, especially for the elderly.
• A research published in the International Tinnitus Journal this past August suggests a possible link between hearing loss and Alzheimer’s, however the exact process remains unknown.
• Memory loss is the most common first symptom of Alzheimer’s disease. The March 2021 study suggests that people may have trouble recalling recent discussions, names, or events. These alterations are more profound than the effects of aging and might start off slowly. Daily life is hampered by them.

According to a research from March 2021, some of the earliest signs of Alzheimer’s disease are:

• Memory loss severe enough to cause problems doing everyday tasks
• incapacity to do routine activities, such as making payments or playing a game
• Dates and times are being forgotten.
• Problems with problem-solving, decision-making, and even routine tasks like grocery shopping and meal preparation due to impaired cognition and judgment.
• Disorientation due to problems with vision and/or spatial perception
• Suddenly developing language difficulties, such as stumbling over words or needing to rewrite passages
• Taking time away from regular activities
• Symptoms of sadness or anxiety-like changes in mood
• Alterations in character, including more volatile behavior

The severity of Alzheimer’s symptoms and the degree of care required increase over the disease’s three phases. Indicators of each phase include the following:

• Mild disease: Disruptions to daily function, memory loss, and confusion may be noticed by friends and family, leading to a diagnosis. At this point, most people are able to continue living on their own. The National Institute on Aging warns that as people age, they may exhibit changes in their mood and demeanor, as well as poor judgment, anxiety, and violence. Handling changes in character manifested by Alzheimer’s disease.
• Moderate Disease:The NIA says, greater surveillance is needed since the disease has spread to other parts of the brain. As a result, people have trouble picking up new skills and completing tasks requiring several steps, including getting dressed. The National Institute of Mental Health (NIA) reports that patients may also experience hallucinations and paranoia, impulsive conduct, wandering, and repeated words or motions.
• Severe Disease: As it progresses, robs patients of their abilities to think, speak, and care for themselves. The National Institute on Aging warns that they may experience problems with swallowing and bowel and bladder control. Aspiration pneumonia, which happens when a person loses the capacity to swallow correctly, is the leading cause of mortality in Alzheimer’s.

Diagnosis

The NIA stresses the need for early detection of Alzheimer’s disease because most current treatments are only effective in the early stages of the illness. Typically, healthcare practitioners may use a battery of tests, including:

• Inquiries concerning a patient’s health background, current symptoms, and any recent changes: In addition to asking the patient, providers will often talk to their friends and relatives.
• Evaluation by a psychiatrist is necessary since some mental health issues might produce symptoms similar to Alzheimer’s disease.
• Memory, problem-solving, focus, numeracy, and lexical fluency may all be gauged with a battery of cognitive tests.
• According to StatPearls, thyroid hormone and vitamin B12 may be measured using blood and urine testing.
• Diagnostic imaging: To rule out other potential causes, a CT scan, MRI, PET scan, or electroencephalogram may be performed.

Diseases that cause brain changes are not the only cause of dementia-like symptoms. It is possible to cure the cognitive symptoms of some diseases. According to the study from March 2021, your doctor should be able to assist you rule out the following reasons for your cognitive decline:

• Depression
• Sleep apnea, a disease that prevents normal breathing patterns during sleep, can be fatal if left untreated.
• Adverse reactions to medication
• Lyme disease is a bacterial illness spread by ticks.
• Disorders of the thyroid
• According to a report published in Cureus22 in February 2020, you may be deficient in vitamins like B12.
• Excessive alcohol consumption

Treatment

Alzheimer’s currently has no treatment options. The goal of treatment is to alleviate symptoms and decrease the course of the disease. According to the NIA, options differ depending on the individual’s circumstances:2

Medications that have been authorized by the US Food and Drug Administration (FDA) are available to treat the symptoms of Alzheimer’s disease at various stages. The NIA reports that because they cannot prevent neuronal death, their benefits are temporary and unevenly distributed. According to a study from March 2021, doctors may occasionally give medication to treat behavioral and mental problems like aggressiveness and hallucinations, but they will do so cautiously owing to the risk of major side effects including stroke.

Aduhelm (aducanumab) is the first pharmaceutical authorized by the FDA that specifically targets an Alzheimer’s mechanism, making it an important step forward in the treatment of brain damage. The NIA claims that data from the ongoing follow-up experiments should become available in the early 2030s. According to the Centers for Medicare & Medicaid Services (CMS), Medicare will only pay for aducanumab beginning in April 2022 if the patient is enrolled in a research study.

The March 2021 research suggests that, for symptoms like aggressiveness and agitation, non-pharmaceutical treatments may be preferable to pharmaceutical ones. Quality of life and brain function may potentially benefit from therapies that don’t include medication. Mental deterioration can be slowed by working out (especially cardiovascular exercise). Memory exercises, psychiatric treatments, and music therapy are all possibilities.

Prevention

There is currently no cure for Alzheimer’s disease, however some risk factors can be mitigated.

• Controlling heart disease requires maintaining a healthy blood pressure and cholesterol level. Make smart food choices to protect your heart.
• Stop smoking and cut back on drinking.
• Regular exercise, especially cardiovascular exercise, may decrease the course of illness.
• Reading, playing games, and making things may all be beneficial to brain health. Formal and nonformal learning both have their benefits.
• Keep up your social life.

The news that you or a loved one has Alzheimer’s disease can be devastating. However, there is a great deal of ongoing investigation into the disease’s origins and potential treatments. If you or a loved one is experiencing cognitive changes, discuss the possibility of a cognitive exam with a doctor.