Alzheimer's disease is a type of dementia that causes problems with memory, thinking and behavior. Its symptoms can take years to develop, worsening over time until they prevent you from leading a normal daily life. It is the most common form of dementia, being responsible for between 60 and 80% of cases and is closely related to aging. Most people with Alzheimer's are over 65 years old. But there are also cases in which this disease can occur in younger people.
It is difficult to determine exactly how many people live with Alzheimer's, since it can often be confused with other types of dementia. “It is probably an underdiagnosed disease, but the World Health Organization estimates that worldwide there will probably be about 50 million people who have Alzheimer's or another dementia,” explains Dr. Marc Suárez Calvet, clinical neurologist at Hospital del Mar de Barcelona and researcher at the Pasqual Maragall Foundation, who explains how the aging of the population means that it is estimated that by the year 2050 this figure will possibly triple, being a real public health problem.
A disease without treatment
Alzheimer's is a chronic disease for which there is currently no curative treatment. Thanks to the research carried out in recent years, it has been possible to begin to understand well all the mechanisms that occur in affected people.
This disease is caused by the accumulation in the brain of two proteins: TAU and beta amyloid. A whole series of changes also take place, including an inflammatory reaction of the brain, loss of the neuronal synapse or connection between neurons, and vascular alterations. “This disease does not appear suddenly, but it can take decades until the first symptoms are visible. But in the asymptomatic phase, all these changes, which we know very well, begin to occur,” says the neurologist.
Although these mechanisms are well known, the truth is that currently the medications that exist are only capable of treating the symptoms of the disease. “Translating all this knowledge we have about Alzheimer's into treatments that modify the evolution of the disease and not only treat its symptoms is the great pending issue we have,” says Dr. Suárez Calvet.
Can it be diagnosed early?
Although the obvious symptoms of Alzheimer's are not visible until many years have passed since the onset of the disease, today it is possible thanks to all the research carried out to diagnose it much earlier. There are a whole series of biomarkers (substances present in the body or that are introduced and that allow us to detect a disease) that make this possible.
The best test to detect Alzheimer's is a lumbar puncture, a procedure used to collect cerebrospinal fluid – a watery, clear, colorless fluid that circulates in and around the brain and spinal cord – which serves both to diagnose the disease in the early asymptomatic as when symptoms have already started. There are also neuroimaging tests and a test is being developed that would allow the disease to be detected with a blood test.
“However, although we can detect the disease in the asymptomatic phase, as we do not have any treatment that modifies the evolution of the disease, there is some debate about whether or not it is advisable to carry out this early diagnosis. When there are treatments, then it will make all the sense in the world to make these diagnoses,” says the expert.
Genetics and risk factors for Alzheimer's
In general, Alzheimer's is not a hereditary disease. It is true, however, that there is a small group of people who suffer from what is known as familial Alzheimer's, where some genes are affected. “But they are very rare and exceptional cases, with very particular characteristics within Alzheimer's, affecting young people between 30 and 50 years old and with slightly different symptoms,” explains Dr. Marc Suárez Calvet.
What is known as sporadic Alzheimer's, which is the most common and the one that almost everyone knows, is a complex disease where many environmental and family factors come into play. Yes, there is a certain genetic predisposition, related above all to a gene called APOE and which is associated with the risk of developing the disease. “But the fact that you have a family member with the disease does not mean at all that you will have it too. And vice versa, not having any history does not mean that it cannot develop,” adds the neurologist.
Apart from the genetic predisposition, a whole series of risk factors are also known, which are common for other dementias:
- Cardiovascular risk factors: High blood pressure, diabetes, cholesterol or a sedentary lifestyle, for example, in addition to being a risk for cardiovascular diseases, they are also a risk for neurological diseases such as Alzheimer's.
- Hearing loss: Having hearing problems is also a risk factor for Alzheimer's, so it is important to treat them.
- Physical exercise: It is extremely positive for the brain to do physical exercise at all ages.
- Social activities: Leading an active life and being in contact with other people also influences a lower risk of developing Alzheimer's.
How to identify the symptoms of Alzheimer's?
Although there are currently no treatments for Alzheimer's that are capable of curing the disease, there are others that can help make its symptoms more bearable. Therefore, it is important that when the first symptoms appear, you consult a neurologist who can perform a proper evaluation. However, one of the most common symptoms of Alzheimer's is precisely anosognosia, that is, not being aware of the disease.
This does not always happen, but it does happen in many patients who do not realize their symptoms. That is why it is important that family members, caregivers and those closest to you be alert to the appearance of any of these problems:
- Cognitive alterations: The most common and recognized is memory loss. The inability to remember recent events or things that were said a few hours ago is the most frequent and characteristic. But other disorders can also occur, such as having language or orientation problems.
- Behavioral alterations: These can be as different as depression, anxiety, sleep disorder, eating disorders and even hallucinations or delusions.
- Functional alterations: The person with Alzheimer's gradually loses the capacity for daily life, preventing them from carrying out previously daily activities that they performed normally.
