What is Alzheimer Disease?
Dementia refers to a noticeable drop in mental abilities, disrupting a person’s daily activities. Alzheimer’s disease (AD) is the most common form of dementia, representing the majority of cases in people 65 and older. Alzheimer’s is a disease that gradually causes impairment of mental functions such as memory, comprehension, language, attention, reasoning, and judgment. While it doesn’t directly cause death, it can make people more susceptible to other health issues which can lead to death.
The Centers for Disease Control and Prevention (CDC) report shows that Alzheimer’s is the seventh most common cause of death in the U.S. in 2022. Prior to the COVID-19 pandemic, it was the sixth. In most cases, Alzheimer’s develops after the age of 65, known as late-onset Alzheimer’s Disease (LOAD). A less common version, Early-Onset Alzheimer’s Disease (EOAD), can happen before 65 and affects about 5% of Alzheimer’s patients. EOAD sometimes shows unusual symptoms, and its diagnosis often happens later, resulting in a more aggressive disease progression.
There have been significant advancements in creating biomarkers for specific and early diagnosis of Alzheimer’s in the last ten years. These biomarkers are identified using brain imaging scans and analysis of cerebrospinal fluid (CSF) and blood for levels of certain proteins.
While there isn’t currently a cure for Alzheimer’s, treatments exist that can help manage some of the symptoms. Researchers have been making strides in developing medications aimed at slowing the progression of the disease, particularly with the discovery of new disease biomarkers.
The symptoms of Alzheimer’s can differ depending on the stage of the disease. There are different stages based on the level of mental impairment and disability a person experiences. These stages include the preclinical (before symptoms show), mild cognitive impairment, and dementia stage, which is further divided into mild, moderate, and severe stages. This is different from the diagnostic criteria or steps used in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5) for Alzheimer’s.
The most common early symptom of typical Alzheimer’s is episodic short-term memory loss. People may have trouble remembering new information but can recall long-term memories. They may have problems solving problems, judgment, and maintaining organizational skills. They may also find multitasking and abstract thinking challenging.
As Alzheimer’s progresses, people can face challenges with daily tasks such as driving, managing money, and planning activities. They may develop language problems and impaired visual-spatial skills. There may also be changes in behavior such as apathy, social withdrawal, restless or aggressive behavior, hallucinations, and aimless wandering. Sleep disturbances, having difficulty with learned motor tasks, and other motor symptoms may occur late into the disease. In the advanced stages, individuals may need constant care.
What Causes Alzheimer Disease?
Alzheimer’s disease is a condition that is characterized by the gradual and steady loss of nerve cells in the brain, often starting in the region known as the entorhinal cortex within the hippocampus. Both genetic and environmental factors contribute to Alzheimer’s, with certain genetic conditions, like Trisomy 21, being associated with a higher risk of early-onset dementia.
Alzheimer’s disease occurs due to many factors, with age being the most critical one. In essence, the older a person gets, the higher their chance of developing Alzheimer’s. For example, starting from the age of 65, the prevalence of Alzheimer’s doubles with every five-year increase in age.
Issues with the heart and blood vessels, collectively called cardiovascular diseases, also increase the risk of developing Alzheimer’s. These diseases can also elevate the risk of other types of dementia caused by strokes. The good news is that by managing these cardiovascular risk factors, people can potentially reduce their risk of developing Alzheimer’s.
Weight problems and diabetes are also significant factors that can increase a person’s chance of developing Alzheimer’s. Excessive weight can lead to diabetes by impairing the body’s ability to use sugar properly. Sustained high levels of sugar in the blood can lead to memory problems by causing the build-up of harmful proteins, known as beta-amyloid, and inflammation in the brain. Obesity compounds this risk by triggering the release of substances that cause inflammation and making the body resistant to insulin.
Head injuries, depression, parental age at the time of a person’s birth, smoking, certain genetic factors, levels of a certain type of protein in the blood (homocysteine) and a strong family history of dementia can all increase the risk of developing Alzheimer’s. For example, having a close relative with Alzheimer’s can increase a person’s risk by 10% to 30%. The risk becomes three times higher for those with two or more siblings with late-onset Alzheimer’s.
On the flip side, there are several things that individuals can do to potentially reduce their risk of developing Alzheimer’s. This includes pursuing higher education, engaging in leisure activities such as reading or playing musical instruments, following a healthy diet, and regular aerobic exercise. In women, estrogen use and anti-inflammatory agents have also been linked to a lower risk of Alzheimer’s.
Risk Factors and Frequency for Alzheimer Disease
Alzheimer’s disease (AD) is mainly seen in older people. There has been a significant increase in the global cases of dementia from 1990 to 2016. In 1990, there were about 20.3 million cases reported. This number grew to 43.8 million by 2016, a substantial increase of 116%. From 1990 to 2019, the number of people with Alzheimer’s disease and other forms of dementia increased by around 148% and 161% respectively. It’s expected that by 2050, the number of people affected by dementia could reach 150 million, which is four times today’s number.
- After the age of 65, the number of people getting Alzheimer’s disease doubles every five years.
- Before age 65, less than 1% get Alzheimer’s each year. But after age 85, it jumps to 6% per year.
- The percentage of people aged 65 and over with Alzheimer’s jumps from 10% to 40% once they reach 85.
- Women are slightly more likely to get Alzheimer’s, especially after turning 85.
Signs and Symptoms of Alzheimer Disease
When diagnosing Alzheimer’s disease (AD), it’s really important to take a full medical history and carry out a complete physical examination. Doctors should collect as much information as possible, even from family members and caregivers, because sometimes the patient might not realize the full extent of their symptoms. It’s also useful to know how well a patient is managing with everyday tasks. This involves looking at both simple activities of daily living (ADL), such as bathing and eating, and more complex tasks known as instrumental activities of daily living (IADL), which cover things like shopping, managing money, cooking, and housekeeping.
Doctors will also need to know the timing, pattern, and speed of disease progression. This involves tracking changes in a patient’s memory, thinking skills, behavior, or ability to function over time. It’s important to review the patient’s medication history too, as some drugs can affect cognitive function. Furthermore, the patient’s lifestyle choices, such as alcohol consumption and any past or present illicit drug use, can also impact brain function and should be taken into consideration.
Alongside this, a thorough physical exam is vital. This will include a detailed neurological exam and mental status assessment to help evaluate the stage of Alzheimer’s disease and rule out other conditions that could be causing the symptoms. In most cases, it’s possible to diagnose Alzheimer’s disease with a good level of accuracy from clinical assessments.
The neurological exam is a crucial piece to the puzzle when diagnosing Alzheimer’s, and it’s specifically used to rule out other potential conditions. With Alzheimer’s disease, this exam tends to be normal, except that the patient may have lost their sense of smell (anosmia). It’s worth noting that anosmia can also occur in people with Parkinson’s disease, dementia with Lewy bodies, or traumatic brain injury (TBI), but not in those with vascular cognitive impairment (VCI) or depression.
Doctors should also perform and document a Mini-Mental Status Exam (MMSE) or, even better, a Montreal Cognitive Assessment Exam (MOCA) as part of the cognitive neurological exam. The MOCA is particularly handy because it’s more sensitive to mild cognitive impairment than the MMSE. Another great cognitive screening test for primary care physicians is the Mini-Cog exam, which includes a clock drawing test and 3-item recall. Interestingly, a person’s level of education doesn’t really influence the results of the Mini-Cog exam.
In the latter stages of Alzheimer’s disease, patients may show more specific neurological signs, such as difficulty forming movements (apraxia) and difficulty with language (aphasia), along with other frontal release signs, and primitive reflexes.
As Alzheimer’s disease progresses, patients might lose their ability to speak and respond to verbal commands, making them heavily reliant on caregivers. In extreme cases, patients may end up bedridden and may even fall into a persistent vegetative state.
During a mental status examination, it’s important for the doctor to evaluate different aspects of cognitive function. These include concentration, attention, memory (both recent and old), language skills, visuospatial skills, praxis (the ability to perform learned movement sequences), and executive functioning (planning and decision-making tools). These assessments are key in evaluating the extent of cognitive decline.
When individuals with Alzheimer’s disease come in for follow-up visits, doctors should always carry out a thorough mental status examination. This allows them to assess the progression of the disease and monitor the development of neuropsychiatric symptoms.
Testing for Alzheimer Disease
If your primary care doctor suspects you may have Alzheimer’s disease (AD), a common type of dementia, they will take several steps to assess your condition. First, they will carefully review both your personal health history and your family’s health history. They will also check any medications you are currently taking, as some can lead to or worsen problems with memory or thinking. To better understand how your memory is working, your doctor may ask you to take cognitive tests, such as the MMSE or MOCA.
Next, your doctor may arrange for blood tests to be done. While these tests won’t directly show if you have AD, they help your doctor rule out other causes of cognitive trouble like low thyroid function or vitamin B12 deficiency. The blood tests taken are usually a Complete Blood Count (CBC), Complete Metabolic Panel (CMP), Thyroid-Stimulating Hormone (TSH), and evaluation of vitamin B12 levels.
Your doctor could also possibly suggest that you undergo different types of brain scans, such as a brain CT (Computed Tomography) scan or an MRI (Magnetic Resonance Imaging). These brain scans could show signs of changes or damage in your brain related to Alzheimer’s, although the changes could also be a result of other conditions or even normal aging. An MRI is generally a more sensitive tool in assessing individuals with dementia when compared to a CT scan.
Estimating the volume of specific areas in the brain, a technique known as ‘volumetric MRI’, can sometimes be utilized with Alzheimer’s patients. This type of MRI can reveal shrinking in the medial temporal lobe of the brain, specifically in the area known as the hippocampus, which is often associated with memory loss in Alzheimer’s disease. While promising, the use of volumetric MRI in early detection of Alzheimer’s and differentiation from normal aging changes is still under study and discussion.
There are more advanced techniques, such as PET (Positron Emission Tomography), fMRI (functional Magnetic Resonance Imaging), and SPECT (Single-Photon Emission Computed Tomography), which provide a map of brain activity and are increasingly being used in research studies for early detection and monitoring of Alzheimer’s disease. However, these functional imaging methods are not yet fully established in making an Alzheimer’s diagnosis.
Electroencephalogram (EEG), a test that measure electrical activity in the brain, is generally not useful for diagnosing Alzheimer’s and other neurodegenerative disorders. While an EEG may show some changes (like slower wave activity) in an Alzheimer’s patient, it’s typically considered a normal finding.
Your doctor may also refer you for neuropsychological testing, which is the most reliable method for detecting mild cognitive impairment – a condition that often develops into Alzheimer’s – in its early stages.
Beyond these methods, recent advancements have led to the development of specific imaging and laboratory tests that can help to diagnose Alzheimer’s in its early stages. However, these are currently mostly used in research settings and are not widely available for routine clinical practice.
Genetic studies are also not usually included in routine Alzheimer’s diagnosis but may be considered in rare cases, especially for families with a history of early-onset AD.
Remember, obtaining a definitive diagnosis of Alzheimer’s even after comprehensive testing is not always possible. Some patients may show signs of mild cognitive impairment, which is a middle stage between normal aging and dementia, rather than full-blown Alzheimer’s disease. These patients may continue to function normally in their daily lives, despite minor cognitive troubles. They are, however, at risk of developing full dementia within 5-7 years and hence should continue to receive follow-up evaluations.
Treatment Options for Alzheimer Disease
Alzheimer’s disease (AD) is a chronic condition that affects the brain, causing problems with memory, thinking, and behavior. It currently has no known cure and doctors focus on managing the symptoms as best as possible in everyday clinical practice.
Two types of medications are approved to help manage AD symptoms – cholinesterase inhibitors and partial N-methyl D-aspartate (NMDA) antagonists.
Cholinesterase inhibitors work by increasing levels of acetylcholine, a chemical that helps nerve cells communicate and is involved in learning and memory. Three drugs in this category that have been approved for treating AD are donepezil (often the first choice for AD with mild dementia), rivastigmine (used in mild cognitive impairment and mild dementia stages), and galantamine (also approved for mild cognitive impairment and mild dementia stages). Common side effects of these medications include stomach problems like nausea, vomiting, and diarrhea. They can also cause slow heart rates, heart rhythm problems, and fainting, so they’re not suitable for patients with severe heart problems.
The partial N-methyl D-aspartate (NMDA) antagonist called memantine helps slow down the buildup of calcium inside brain cells. The side effects may include dizziness, body aches, headache, and constipation. Memantine is approved for treating moderate to severe AD. It can work together with cholinesterase inhibitors, particularly in individuals with moderate to severe AD.
As our understanding of AD has evolved, newer treatments that modify the disease itself are being developed, targeting the earlier stages of the disease. Some, such as Aducanemab, and Lecanemab, and potentially Donanemab, are a type of targeted therapy known as monoclonal antibodies, which work by removing harmful proteins (in this case, amyloid) from the brain. These drugs have shown the ability to reduce the burden of amyloid-beta in the brain and slow cognitive decline, but some patients may experience changes seen on brain scans, known as Amyloid Related Imaging Abnormalities (ARIA), which can cause brain swelling and bleeding.
Along with medication, it’s essential to manage accompanying symptoms like anxiety, depression, and psychosis, especially in the later stages of AD. Certain antidepressants and antipsychotic medications can help, but it’s important to use these cautiously due to possible side effects like stroke, and increased risk of death. Simple strategies such as creating a safe environment, addressing personal comfort needs, providing comforting objects, redirecting attention, removing hazardous items, and avoiding confrontations can be beneficial in managing behavioral issues.
Maintaining good sleep hygiene can enhance the quality of life for individuals with AD. Strategies to enhance sleep include exposure to sunlight, physical exercise during the day, and establishing a bedtime routine to regulate the sleep-wake cycle.
Regular aerobic exercise can also help to slow the progression of AD. The effectiveness of these treatments varies between individuals, and if no significant benefits are seen or if a patient experiences intolerable side effects, the treatment plan should be reevaluated.
What else can Alzheimer Disease be?
When doctors try to diagnose Alzheimer’s disease, they also have to consider a range of other conditions that might be the real source of the patient’s symptoms. Some of these conditions include depression, Lewy body dementia, vascular dementia, frontotemporal lobar degeneration, age-related memory problems, drug or alcohol abuse problems, a lack of vitamin B12, problems related to dialysis, issues with the thyroid, and the impact of taking multiple different medications.
About 15% of all dementia cases are caused by Lewy body dementia (DLB). In people with DLB, there are identifiable bodily changes, including brain cell inclusions that contain certain proteins. This condition could be diagnosed if the patient has symptoms such as changes in mental abilities, visual hallucinations, signs of Parkinson’s disease, REM sleep disorder, and sensitivity to antipsychotic medications.
Frontotemporal dementia (FTD) is another condition that can look similar to Alzheimer’s disease. The people who have FTD tend to start showing symptoms around age 53, and it is more common in men. Symptoms of FTD include personality changes, language problems, and dementia. There are two types of FTD: one featuring behavioral changes and another that impacts language abilities. To diagnose FTD, doctors look for specific symptoms and also use imaging tests to identify changes in the brain.
Dialysis dementia is rare but can occur in people who are receiving long-term dialysis treatment. This problem can be caused by a range of factors, including vascular problems and metabolic abnormalities. The exact cause of this type of dementia is still not fully understood.
Alzheimer’s disease symptoms can be quite different depending on the patient’s age. For most patients over the age of 70, memory loss is the first symptom. However, for patients diagnosed before the age of 60, symptoms may also include impaired judgment and problems with spatial abilities. The list of possible symptoms includes:
- Issues with language and spatial orientation
- Trouble with visual perception and other symptoms related to the back part of the brain, while memory and personality remain relatively unaffected
- Primary progressive aphasia, which primarily impacts language and spares memory in the early stages
- Executive function disorders, where decision-making abilities are more impacted than memory
What to expect with Alzheimer Disease
Alzheimer’s disease is a condition that progressively worsens over time. On average, those aged 65 or older who are diagnosed with Alzheimer’s disease may live for about 4 to 8 years. However, in some instances, individuals with Alzheimer’s disease may live up to 20 years after firstly showing signs of the disease.
Due to Alzheimer’s, the overall physical strength and immune function of patients generally deteriorate. This, along with mobility issues and trouble swallowing, makes Alzheimer’s patients susceptible to infections. Pneumonia, in particular, is quite common among these patients and is often the cause of death.
Possible Complications When Diagnosed with Alzheimer Disease
According to the latest statistics from the CDC in 2023, Alzheimer’s disease (AD) is the sixth leading cause of death, resulting in around 120,000 fatalities every year. The disease mainly affects people over the age of 65, making them more prone to health complications that could drastically affect their lifestyles. Complications from Alzheimer’s can be broadly divided into mental/behavioral and physical challenges.
Mental and behavioral complications:
- Depression: Many Alzheimer’s patients also experience depression which complicates the management of their condition. Some symptoms include changes in mood, trouble sleeping, isolation from social activities, and problems concentrating.
- Agitation and delirium: Patients in advanced stages commonly suffer from confusion and excessive restlessness, especially in the late afternoon or evening, a phenomenon called “sundowning”. Managing these symptoms is crucial to ensure their safety and comfort. However, using antipsychotic medications has several risks, including an increased chance of death and other adverse effects.
- Wandering: It is not uncommon for people with AD to wander off without any specific aim or direction.
Physical complications:
- Fever and infections: Elderly individuals with AD commonly suffer from fevers and infections, especially those related to the respiratory system and urinary tract. Difficulties in swallowing can result in aspiration pneumonia, which exacerbates their health condition.
- Dehydration and malnutrition: Alzheimer’s patients often face difficulties with maintaining proper hydration and nutrition.
- Falls: Due to impaired physical coordination, falls are a common issue among people with AD.
- Bladder and bowel problems: The disease can also cause issues with bladder and bowel control.
Recovery from Alzheimer Disease
Exercise and rehabilitation are key to both treating and preventing dementia. Regular physical activity has been found to greatly help individuals with dementia, by enhancing their mental function, preventing falls and improving their ability to perform daily tasks. In addition, participating in regular physical activities can decrease the occurrence of mental health issues like depression in dementia patients.
While there isn’t yet a specific set of guidelines for exercise routines for dementia patients, researchers are always on the look out to find the most effective forms of exercise, along with their intensity and duration. Currently, they suggest that exercises ranging from moderate to high intensity could provide more benefits than less intense activities.
Caregivers and healthcare teams play an important role in providing constant care and necessary support for individuals with dementia. Given these individuals might find it hard to remember information, regular reminders and guidance are crucial for helping them maintain their abilities to function and quality of life.
Preventing Alzheimer Disease
Alzheimer’s Disease (AD) is a common health problem worldwide. Even though this is the case, there are no specific rules for what kind of training or qualifications healthcare providers must have to offer care to patients with this condition.
It’s incredibly important that both patients and their caregivers learn more about Alzheimer’s Disease as this can greatly improve the level of care that Alzheimer’s patients receive. A team success model is crucial here and should include doctors, social workers, therapists, and family members all working together to provide total care. Moreover, it’s key that theory taught in education is properly applied in a practical, real-world setting, to give Alzheimer’s patients the care they need.
