Alzheimer’s Disease: Causes, Symptoms, Treatment and Prevention Tips
Alzheimer’s disease (AD) is a progressive brain disorder that slowly causes a decline in memory and other cognitive functions. It is one of the most common forms of dementia – a group of symptoms associated with loss of memory and other mental abilities that are severe enough to interfere with daily life. Alzheimer’s disease accounts for 60 to 80 percent of all dementia cases.
Alzheimer’s disease is named after Dr. Alois Alzheimer, a German psychiatrist and neuropathologist, who was first identified it. In 1906, Dr. Alois noticed changes in the brain tissue of a woman who had died of an unusual mental illness. Her symptoms included memory loss, language problems, and unpredictable behavior. After she died, he examined her brain and found many abnormal clumps called amyloid plaques and tangled bundles of fibers called neurofibrillary tangles (NFTs) or tau.
Scientists continue to unravel the complex brain changes involved in the onset and progression of Alzheimer’s disease.
During this preclinical stage of Alzheimer’s disease, proteins build up in the brain to form structures called ‘plaques’ and ‘tangles’. This leads to the loss of connections between nerve cells, and eventually to the death of nerve cells and loss of brain tissue.
As neurons die, additional parts of the brain are affected. By the final stage of Alzheimer’s, damage is widespread and brain tissue has shrunk significantly. At this stage, individuals experience not only a significant decline in mental function but also in physical capabilities. They are likely to need extensive help and assistance with daily activities.
Alzheimer’s is a terminal illness, and no cure is currently available. The average person diagnosed with Alzheimer’s has an estimated lifespan of about 4-8 years after diagnosis, but some people can live with Alzheimer’s for up to 20 years.
According to Alzheimer’s association, an estimated 5.5 million Americans of all ages have Alzheimer’s disease. The majority of people with Alzheimer’s are 65 and older, but Alzheimer’s is not just a disease of old age. Approximately, 200,000 Americans under the age of 65 have younger-onset Alzheimer’s disease.
What are the causes and risk factors of Alzheimer’s?
Scientists don’t know exactly what causes Alzheimer’s disease, but they have identified factors that increase the risk of Alzheimer’s. These include:
Although Alzheimer’s is not a normal part of aging, but the greatest risk factors of Alzheimer’s disease is increasing age. In fact, most individuals with Alzheimer’s disease are over the age of 65 and the amount increased nearly half of those aged over 85.
Another major risk factor of Alzheimer’s disease is genetic. Scientists have identified two different kinds of genes that increase a person’s chances of developing Alzheimer’s: Risk genes and deterministic genes.
Risk genes increase a person’s likelihood of developing Alzheimer’s, but they do not guarantee it will happen. That’s means, even if you carry this gene, there is not a 100 percent likelihood that you will develop the disease. The primary risk gene that is thought to be associated with AD is called apolipoprotein E-e4, or APOE-e4. It is the first risk gene identified and remains the one with strongest impact.
The other genes associated with Alzheimer’s are deterministic genes, which are much rarer than risk genes. If a deterministic gene is inherited, there is 100 percent certainty that the person will develop Alzheimer’s, probably before the age of 65.
If a person has one of these genes, he or she has almost 100 percent chance of developing AD, probably at a much earlier age. Some examples of the deterministic genes are amyloid precursor protein (APP), presenilin-1 (PS-1) and presenilin-2 (PS-2).
People who have a parent or siblings with Alzheimer’s are more likely to develop the disease. The risk increases if more than one family member has been affected by the disease.
Apart from the age, family history, and genetic factors, research has shown that lifestyle factors such as diet, physical activity, and social engagement, can affect someone’s Alzheimer’s risk as well.
What are the symptoms of Alzheimer’s?
The early symptoms of Alzheimer’s vary from person to person. They are commonly mild to start with, but they get worse over time and start to interfere with daily life.
For most people with Alzheimer’s, the first signs are memory problems, particularly difficulty recalling recent events and learning new information. These symptoms occur because the early damage in Alzheimer’s is usually to a part of the brain called the hippocampus, which has a central role in day-to-day memory.
Although memory problems are usually the earliest symptoms of Alzheimer’s, someone with the disease will also have mood and personality changes. They may become anxious, irritable or depressed. Many people become withdrawn and lose interest in activities and hobbies.
People with moderate Alzheimer’s may have difficulty concentrating and take much longer to do things than they did before. They may also have trouble following or joining a conversation. They may struggle with vocabulary, have problems finding the right word or call things by the wrong name.
As Alzheimer’s progresses, problems with memory loss, communication, reasoning and orientation become more severe. People with Alzheimer’s may develop behaviors that seem unusual or out of character. These include agitation repeating the same question, disturbed sleep patterns or reacting aggressively. Such behaviors can be distressing or challenging for the person and their career. They may require separate treatment and management to memory problems.
In the later stages of Alzheimer’s disease, someone may become much less aware of what is happening around them. They may have difficulties eating or walking and become increasingly frail. Eventually, the person will need help with all their daily activities.
It is important to remember that every case is unique, and if you notice any of the symptoms in yourself or someone you know, schedule an appointment with your doctor. Early diagnosis and treatment may slow the progression of the disease and delay the cognitive decline.
How Alzheimer’s is diagnosed?
Currently, there is no single test that confirms you have Alzheimer’s disease. Your GP will determine whether Alzheimer’s is the most likely cause of your symptoms based on the information you provide and results of various tests that can help clarify the diagnosis.
While physicians can almost always determine if a person has dementia, it may be difficult to determine the exact cause. Diagnosing Alzheimer’s requires careful medical evaluation. These include:
Physical and neurological exam
Your doctor will perform a physical exam and is likely to check your overall neurological health by testing your:
- Muscle tone and strength
- Sense of sight and hearing
- Ability to get up from a chair and walk across the room
Blood tests may help doctor to rule out other potential causes of memory loss and confusion, such as thyroid disorders or vitamin deficiencies.
Brain-imaging technologies may enable doctors to detect specific brain changes caused by Alzheimer’s. These include:
- Magnetic resonance imaging (MRI). An MRI uses radio waves and a strong magnetic field to produce detailed images of your brain. MRIs are used to rule out other conditions that may account for.
- Computerized tomography (CT). A CT scan produces cross-sectional images (slices) of your brain. It’s currently used primarily to rule out tumors, strokes and head injuries that may cause cognitive change.
- Positron emission tomography (PET). During a PET scan, you’ll be injected in a vein with a low-level radioactive tracer. The tracer may be a special form of glucose (sugar) that shows overall activity in various brain regions. This can show which parts of your brain aren’t functioning well.
Can Alzheimer’s be treated?
While there is no cure for Alzheimer’s disease, but there are drug and non-drug treatments that may help with both cognitive and behavioral symptoms.
Alzheimer’s medications can temporarily alleviate some symptoms or slow down their progression in some people. Two types of drugs that are currently used to treat Alzheimer’s or dementia symptoms are:
Cholinesterase inhibitors. These medications work by boosting levels of a cell-to-cell communication by providing a neurotransmitter (acetylcholine) that is depleted in the brain by Alzheimer’s disease. Cholinesterase inhibitors can improve neuropsychiatric symptoms, such as agitation or depression, as well.
Commonly prescribed cholinesterase inhibitors include donepezil (Aricept), rivastigmine (Exelon), and galantamine (Razadyne). The main side effects of these drugs include diarrhea, nausea, loss of appetite and sleep disturbances. In people with cardiac conduction disorders, serious side effects may include a slow heart rate and heart block.
Memantine (Namenda). This medication keeps brain cells from using too much of a brain chemical called glutamate, which Alzheimer’s-damaged cells make too much of. The drug seems to protect against nerve damage and has fewer side effects than other drugs. It may keep moderate to severe symptoms from getting worse quickly. People who have moderate to severe Alzheimer’s disease may take this drug along with donepezil, rivastigmine, or galantamine.
Sometimes other medications such as antidepressants may be prescribed to help control the behavioral symptoms associated with Alzheimer’s disease. But some medications should only be used with great caution. For example, some common anti-anxiety medications, such as clonazepam (Klonopin) and lorazepam (Ativan), increase the risk of falls, confusion and dizziness. Always check with your doctor before taking any new medications.
Non-drug treatment such as get physically active, stress management, and cognitive therapy may also help.
Be physically active. Being physically active is an important part of everybody’s wellness plan, and those with Alzheimer’s are no exception. Activities such as brisk walking and swimming can help improve mood and maintain the health of joints, heart and the brain.
Exercise can also promote restful sleep and prevent constipation. People with Alzheimer’s who develop trouble walking may still be able to use a stationary bike or participate in chair exercises.
Stress management. Chronic or persistent stress can lead to shrinkage in areas of the brain associated with the regulation of emotions, metabolism, and memory, increasing the risk of Alzheimer’s disease and dementia. To de-stress, try these stress management techniques.
Cognitive therapy. There are several types of cognitive therapy that could benefit people with Alzheimer’s. These therapies are designed to stimulate thinking skills and engage people who have Alzheimer’s. They are often group-based and include games with an emphasis on enjoyment. The benefits of cognitive therapy for people with Alzheimer’s could include improvement in memory, thinking skills and quality of life.
Other types of cognitive therapy are currently being tested to see if they can benefit people with dementia. These include reminiscence therapy, where past activities and experiences are discussed, usually with photographs and other familiar objects from the past.
Are there ways to prevent Alzheimer’s disease?
As the exact cause of Alzheimer’s disease is still unknown, there’s no way to prevent the condition. However, there are steps that you can take to reduce the risk of developing Alzheimer’s disease.
Eat a healthy diet
Diet play an important role in brain health and may help ward off Alzheimer’s. Try to consume plenty of omega-3 rich foods and limit the intake of fast foods, fried, packaged foods, and anything that contains “trans fats” as these fats can cause inflammation and produce free radicals – both of which are hard on the brain.
In addition to slowing down the progression of cognitive decline, exercise can also help in preventing Alzheimer’s disease. According to the Alzheimer’s Research & Prevention Foundation, regular physical exercise can reduce the risk of developing Alzheimer’s disease by up to 50 percent.
Exercise protects against Alzheimer’s by stimulating the brain’s ability to maintain old connections as well as make new ones.
Try to aim for at least 150 minutes of moderate intensity exercise each week. The ideal plan involves a combination of cardio exercise and strength training. Good activities for beginners include brisk walking and cycling.
Smoking is one of the most preventable risk factors for Alzheimer’s disease. One study found that smokers over the age of 65 have a nearly 80 percent higher risk of Alzheimer’s than those who have never smoked. If you still smoke, now is the time to quit.
Keep your brain active
Those who continue learning new things throughout life and challenging their brains are less likely to develop Alzheimer’s disease and dementia. Activities that help keep the brain active include:
- Learning new languages
- Playing puzzle games
- Reading frequently
- Listening to the music or radio
Control blood pressure and cholesterol levels
Both high blood pressure and high total cholesterol are associated with an increased risk of Alzheimer’s disease. Improving those conditions are good for your brain as well as your heart. So, make sure your blood pressure and cholesterol levels are controlled.