Alzheimer’s disease, a most common cause of dementia
Alzheimer’s disease (AD) is the most common cause of dementia, which is the cause of 60% to 70% of cases of dementia. The most common early symptom is difficulty in remembering recent events (short-term memory loss). This diminishes the ability to carry out daily activities. A patient with AD may finally forget their loved ones. This is painful for both the patients and their families.
AD is an aging-related disease and its incidence increases with age. It predominantly affects the elderly who aged 65 or older and this form of the disease is known as the late-onset AD. But AD is not just a disease of old age — people younger than 65 also develop the disease, which is known as the early-onset AD.
Although AD is an incurable disease and currently no effective therapies are available to reverse or stop its progression, it is necessary to learn some knowledge about it so that we can know which things may be good and which things may be bad in the context of this disease. Raising the public awareness of AD is also very important given that the prevalence of AD is anticipated to increase due to factors like aging population and extended lifespan.
Causes of Alzheimer’s
A better understanding of the cause of a disease will inform better strategies to overcome it. Unfortunately, the cause of AD is poorly understood. But previous studies have shed some lights on this problem.
It’s now believed that 70% of the risk is genetic. Lots of candidate risk genes have identified. A gene called APOE, which encodes the protein apolipoprotein E, may be the most significant one. Individuals carrying one or two copies of the APOE e4 allele are at a much higher risk of developing AD compared with those who do not have the APOE e4 allele.
In addition to genetics, there are a variety of other risk factors of AD, including older age (the biggest risk factor), being female, a history of head injuries, Down syndrome, depression, and hypertension, high cholesterol, heart attack or other cardiovascular disorders.
Symptoms and diagnosis of Alzheimer’s
Loss of memory is a typical symptom of AD. Besides, there are a variety of other signs and symptoms, such as a decline in thinking and reasoning skills, problems with language, confusion with time or place, mood problems such depression, loss of motivation, inability to carry out daily activities, and other behavioral problems. These symptoms may develop and get worse over a long period of time. Patients with the disease generally die within 3 to 9 years after diagnosis.
The diagnosis of AD is based on a complete medical assessment of cognitive or behavioral function and performance. Besides, many other methods are also used to aid in its diagnosis. Doctors will investigate the person’s family history of AD, medical history, medication history, and changes in personality. Tests, such as blood and urine tests using ELISA kits or other diagnostic tools, can also help determine if the person’s symptoms are caused by other illnesses or conditions. Powerful brain scans like CT, MRI, and PET are also useful in the diagnosis of AD.
Treatment of Alzheimer’s
Despite progress in identifying genes involved in AD, understanding the pathogenesis of the disease, and developing medications to ease some symptoms, there is still no strategies to reverse or stop its progression. Since the affected people may have difficulties in carrying out daily activities and taking care of themselves, they often need others’ help. The caregiver may find it hard to cope with this type of burden, which includes social, psychological, physical, as well as economic elements.
In addition to drug treatment, there are other treatments for Alzheimer’s disease. Physical exercise is known to have numerous health benefits such as lowering the risk of certain diseases (cardiovascular disease and diabetes), improving the bones and muscles, and cutting stress. Research finds that exercise may also benefit the brain. For example, exercise several times a week may improve thinking, reasoning and learning skills. For those with AD, exercise may improve memory, cognition and other brain functions. For those with a risk of AD, exercise may delay the onset of the disease.
Antipsychotics are used to deal with behavioral problems or psychosis caused by dementia but are not usually recommended, as there is little benefit with an increased risk of early death.
Prevention of Alzheimer’s
First, it must be emphasized that no effective, preventive measures have been proven. Previous studies in this field have led to mixed results. Some suggest a possible link between certain modifiable factors and the risk of AD. These factors may include diet, cardiovascular risk, certain medications or intellectual activities. Their association with AD warrants more investigation.
Some studies suggest that statins, drugs that help lower cholesterol, might reduce AD risk. Long-term usage of non-steroidal anti-inflammatory drugs (NSAIDs) appears to be related to a reduced risk of AD, and these drugs seem to reduce inflammation related to amyloid plaques. However, there is still a lack of evidence that supports the preventive effects of these drugs in AD.
Regular physical exercise may cut the risk of AD by 50%. Exercise improves cardiovascular disorders.
Disrupted sleep is not only a symptom of AD, but also a possible risk factor. So, ensure high-quality sleep if you want to reduce your AD risk. This is because uninterrupted sleep is critical for flushing out brain toxins.
AD often involves inflammation and insulin resistance. It’s believed that there is a strong link between metabolic disorders and the signal processing systems.
A healthy, Japanese, or Mediterranean diet is associated with a lower risk of AD, whereas a diet high in saturated fats and simple carbohydrates correlates with a higher risk.
Tea and coffee are also brain healthy. Moderate consumption of these drinks may have beneficial effects with regards to prevention of AD.
DHA found in the healthy fats, such as cold-water fish, has been shown to reduce beta-amyloid plaques and prevent AD.
Bess Liu is a writer who often writes articles about human health and diseases. She works at Cusabio, a company that serves scientists in the field of biomedical research.