What is cognitive reserve and why it could be essential against Alzheimer’s

This week has been commemorated World Alzheimer’s Day, a neurodegenerative disease that seriously affects the quality of life, both for those who suffer from it and for their loved ones. The scientific and medical community observes with concern the increase in its incidence rate, almost at the same time as the lengthening of life expectancy.

Alzheimer’s disease is the most common form of dementia, accounting for around 70% of cases, and according to World Health Organization data, more than 50 million people worldwide suffer from some type of dementia. , 60% of which reside in low- and middle-income countries. The trend shows that every year 10 million new cases are added; It is estimated that by 2030 the figure will reach 82 million people affected.

Dementia affects thinking, orientation, comprehension, calculation, learning ability, language and judgement. Although its best known manifestation is in the effects it has on memory. In its earliest phase, it is common to have a tendency to forget, or a loss of the notion of time, as well as a dislocation in relation to space.

These symptoms usually go unnoticed until their progression reveals the catastrophe: in the late stage, patients have difficulty recognizing relatives and acquaintances, their behavior is erratic and can even become aggressive, to which are added other problems. which make their autonomy impossible. In fact, dementia is one of the leading causes of disability and dependency among older people worldwide.

“If there’s a memory lapse that’s sustained and consistent over time, not minor things like forgetting keys or going on a date, but something big like losing money, then you need to see a specialist,” says neurologist Isabel Behrens. from the German Maria clinic. And it must be done in time, because “the sooner you try to stop the disease, the slower it will progress and the more cognitive abilities will be saved”.

Dementia, in general, is usually associated with the older adult population. However, it would be a mistake to claim that it is a natural cause of old age. “If it were a process associated with aging, all older people would have to suffer from dementia, but only one in three people suffer from it,” says Álvaro Romero, neurologist at Clínica Indisa. “That’s why the old concept of senile dementia has been removed from the neurological literature,” he adds.

However, the deterioration that the passage of years implies makes the elderly more susceptible to developing this type of disease. Figures indicate that between 5 and 8% of the population over 60 suffer from some type of dementia, a rate that increases exponentially once the 85 barrier is exceeded, fluctuating between 25 and 50%.

The problem is that as life expectancy increases – although this may vary due to the pandemic – the number of cases should also increase. Especially in women, whose incidence rate is higher. “Many studies say that between five and ten times more than men”, details Romero.

According to the neurologist, this is mainly due to two aspects. The first is that women tend to live longer than men, so there is a larger population of that sex at risk. And on the other hand, “it seems that hormones, especially estrogen, play a protective role against dementia”, but after menopause this barrier gives way and leaves the female brain more vulnerable to the development of neurodegenerative diseases.

The only good thing about the rising numbers is that there is greater worldwide awareness of dementia, which is leading to more research and high-tech designs, enabling increasingly accurate diagnoses. .

In addition to the people directly affected – such as the dead, the seriously infected and the people who left after-effects – covid-19 also claimed countless other types of victims. Cabin syndrome (a kind of phobia of leaving the house) or brain fog (which affects cognitive functions) have hit the headlines around the world, especially during the months of confinement, due to the number of cases that have proliferated.

Dementia also made a bigger dent during the most intense time of the pandemic. “There was an increase in cases, or a worsening, but it is difficult to realize it, because we remained several months without consultations”, explains Behrens.

Although the virus is not directly responsible for all mental illnesses, the uncertainty it has generated and the health restrictions it has created have created an environment conducive to the development or worsening of ailments such as anxiety. , stress and anxiety, as well as pathologies such as depression.

Added to this is an economic crisis and a general doubt about the future that generate a level of stress that affects our neuronal capacity and, with it, memory.

“These stimuli cause the release of cortisol, a hormone which, at high concentrations, and all the more so if it is constant over time, becomes toxic and kills neurons. This is how memories get lost. And when a neuron dies, it is very difficult for it to regenerate again,” explains Camila Calfio, doctor of biotechnology and researcher at the International Center for Biomedicine (CCI), where she is dedicated to studying methods of combating Alzheimer’s disease.

Insomnia and lack of sleep are other situations that increase in this type of context and which also generate a negative effect on the neural processes related to memory. It’s that when we sleep, we reject “unnecessary” information from the brain and new memories are incorporated into the mental hard drive.

Some authors describe cognitive reserve as the ability of the brain to better tolerate the effects of neuropathologies such as dementia, before reaching the threshold where symptoms begin to manifest. “To put it in a way, it’s like a backup of the main memory that is saved on a second hard drive,” explains Álvaro Romero.

Cognitive reserve develops throughout life and an intellectually, socially and physically active lifestyle is essential to this. There are studies which show that people with greater consistency in these variables, especially since childhood, showed cognitive reserve with a greater ability to alleviate the symptoms of Alzheimer’s disease.

Camila Calfio explains that the risk factors that affect the development of dementia, and in particular Alzheimer’s disease, are divided into two: some modifiable and others non-modifiable. These are linked to each person’s genetic heritage, over which there is no possible control, at least until now.

The first group, on the other hand, is related to aspects of one’s lifestyle: cognitive stimulation, physical exercise and maintaining a healthy life. “If measures are taken regarding these factors, which can be modified, up to 40% of cases of Alzheimer’s development could be reduced”, explains the CCI researcher.

In short, actions to prevent the development of dementia, or its symptoms, must focus on the lifestyle that is maintained. Here are some tips that specialists give in this regard:

• Have a socially active life “Not isolating yourself at home and trying to interact with other people,” says Behrens.
• Stimulate cognitive functions : It seems important to constantly learn new things. Behrens recommends taking classes or workshops, no matter the topic or topic. The bottom line is that it provides a stimulating intellectual challenge, not to lose momentum halfway through. The neurologist says that this measure is interesting because, in addition to promoting cognition, it also contributes to social activity, since in these cases “friendships can be created”.
• Read and listen to music: are also ways to boost cognition, as well as playing strategy and brain games such as chess, crosswords, puzzles, Sudoku something that can be done from the mobile phone or computer, in case you don’t have the hardware tools at home.
• stimulating apps : To get the most out of the technology, Behrens recommends brightness a program that offers various science-based games that allow you to exercise the brain in terms of memory, flexibility and processing speed, among other aspects.
• stay physically active : physical exercise is important, as Camila Calfio explains, because it allows the release of a hormone called irisin, “which travels in the blood and activates neurotrophic factors, which cause greater connection between neurons”, stimulating a whole cascade of cellular benefits in the brain. Álvaro Romero says the ideal is to have at least 120 minutes – two hours – of physical activity per week. This can mean walking 20 minutes a day or doing two hour-long workouts every seven days. “It decreases the possibility of developing dementia,” he says.
• Beware of risk factors : cardiovascular diseases, diabetes, obesity, hypercholesterolemia and arterial hypertension can influence the development of neurodegenerative diseases. As well as tobacco, which experts recommend quitting completely. Alcohol should also be consumed in moderate doses. Avoid blows, especially to the head, and pay attention to your hearing — don’t listen to very loud music through headphones — as there is a strong association between this problem and the development of dementia.