12 May 2017

Getting old without getting old

Post -science

sen.jpgTogether with Ivan Limbach Publishing House we publish an excerpt from the book "Getting old without getting old. On vital activity and aging" by Professor of Gerontology Rudi Westendorp, dedicated to increasing life expectancy and those ways that allow you to maintain health for a longer period.

New causes of death

The recent history of developed countries clearly shows that a person's life path has changed a lot. If earlier the venerable age was the privilege of a few, those who managed to safely pass the underwater reefs of life, today, as a rule, people live to old age. The aging process has become noticeable and tangible for almost everyone, and we can all point to the same signs. We reach the age of much older than fifty, the threshold to which, with normal care, our body recovers and is not subject to serious defects. After fifty, chronic diseases and disorders gradually become noticeable in our life. The disappearance of deadly infectious diseases and the appearance, at the same time, of chronic diseases and various disorders — a change in the causes of mortality — is called an epidemiological transition.

Many believe that we are now dying from "new diseases", but most of the new diseases are not new at all. In the past, they either could not be recognized, or were called something else, because only very few lived to the age when these diseases could manifest themselves. There has been an explosive increase in the number of patients with heart disease and vascular diseases due to atherosclerosis (calcification of blood vessels) — loss of elasticity and narrowing of blood vessels. This epidemic is attributed to an increase in well-being, but upon closer examination it becomes clear that the relationship between well-being and atherosclerosis is not at all unambiguous and can be interpreted in different ways. According to popular opinion, the cause of our ailments is universal well-being, because we smoke, eat too much and move too little. But meanwhile, representatives of the highest social strata — those who enjoy the greatest well—being - are just moving on to a healthy lifestyle. Atherosclerosis affects, as a rule, elderly people from lower social strata. It appears because now we are getting old enough to become a victim of this disease. Age is the most important risk factor, and many elderly people who are not overweight, have never smoked, and lead a mobile lifestyle eventually develop heart disease and vascular diseases.

There are clear indications that atherosclerosis is not developing due to current well-being and that it is not a new disease at all. This is confirmed by studies of mummified bodies of people who died many years ago; now mummies are studied using modern X-ray technology. It turns out that middle-aged men and women who died in the distant past already show signs of atherosclerosis. For a long time, doctors believed that this disease was just a consequence of poor nutrition, causing the deposition of cholesterol on the walls of blood vessels. Now, however, the prevailing opinion is that damage to the walls of blood vessels is caused primarily by prolonged inflammation. Cells of our immune system penetrate from the bloodstream into the inner walls of blood vessels. Once there, they react to cholesterol coming from food, and an inflammatory reaction develops. It damages the walls of blood vessels, because the immune system behaves as if it is dealing with the penetration of an external infection, which should be destroyed at any cost. And elastic, well-permeable blood vessels become narrowed and stiff.

Prolonged inflammation of the vascular walls can be considered as an undesirable side effect of our immune system. Therefore, longevity is associated with a serious risk of atherosclerosis. In principle, there can be no objection to a strong immune system capable of immediately engaging in the fight against external pathogens. But if the fight is carried out too fiercely, if the inflammatory reaction is excessively prolonged, or if your own body is attacked without any exposure to pathogens, then the shortcomings of the immune system become too noticeable. However, in the light of evolution, everything looks completely different. If, in order to survive, you must have the ability to fight pathogens and if at the same time women must be able to tolerate pregnancy, a balance must be established in the immune system.

Healthy and diseased vessels // Oregon State University. Flickr.com

The fact that much later, in old age, you will develop atherosclerosis is irrelevant. Elderly people suffering from atherosclerosis have an unintended side effect of an effective immune system designed to fight influenza, tuberculosis and other infectious diseases. This property is called antagonistic pleiotropy — an important concept to explain the aging of organisms. It means the following: a property developed during natural selection has various (pleiotropy) consequences for an individual and in old age has a negative (antagonistic) effect on his survival. Atherosclerosis is primarily a manifestation of the aging process. If in youth, due to increased well-being, the risk of mortality from infectious diseases decreases, then at the same time — indirectly — in old age, the risk of mortality from cardiovascular diseases increases.

Antagonistic pleiotropy is a good comprehensive explanation of diseases. Crohn's disease[1] or ulcerative colitis (chronic inflammation of the mucous membrane of the colon) is accompanied by an increased risk of atherosclerosis. Chronic gum inflammation (periodontal disease) is also accompanied by an increased risk of atherosclerosis. An acceptable evolutionary explanation could be that patients with Crohn's disease, ulcerative colitis or periodontal disease have a stronger immune system than others, which leads to the development of a general antibacterial inflammatory reaction, which apparently affects the walls of blood vessels. An alternative explanation may be that such patients are carriers of a certain type of bacteria that causes this inflammatory reaction. But the immune system can deviate even more from the right path. Patients with rheumatoid arthritis develop an inflammatory reaction in the absence of any causative agent of the disease. After a few years, it leads to joint destruction and atherosclerosis.

All biological systems of the body and brain are primarily aimed at procreation and survival in the young years. Not only our immune system, but also the energy economy of our body has evolved for the same purpose. American geneticist James Neal characterized man as the result of natural selection aimed at economical energy consumption. Those who, when food is scarce, need fewer calories — so to speak, arranged more "economically" — get a better chance of survival. Over the years of evolution, we have developed the habit of constantly searching for food and consuming it efficiently. When there is a shortage of food, you have to eat everything that comes to hand. That's why we eat with such pleasure, and in times of abundance, many of us eat to the brim.

In addition to the passion for food, natural selection, aimed at achieving efficiency, explains why we get fat so quickly and why we should lose weight. In developed countries, overweight and — as a consequence — the risk of diabetes is the price we have to pay for easily available food, which is now sold literally on every corner.

However, overweight is not only a problem of developed countries. Even a developing country like Ghana is struggling with obesity. Wealthy people live in its capital, Accra. They do not experience hardships, but they are biologically programmed to be economical. A fatal combination — and in the capital, the percentage of overweight people is constantly growing. In developing countries, obesity is a status symbol: it means you can pay for everything you ate! These countries face a double problem. It is necessary to combat child mortality in backward areas where hunger and poverty prevail. At the same time, in cities where industrial development is underway, there is an explosive increase in the number of elderly people with overweight, diabetes and cardiovascular diseases. In addition, in developing countries, the predominant causes of mortality are no longer poverty and infectious diseases, but diseases that arise as a result of affluence or in the process of aging. That's what the local healthcare should pay attention to as soon as possible.

Medical and technical revolution

Since the 1950s, we have known that the process of atherosclerosis has a very long run-up. At the autopsy of American soldiers who died in the Korean war, it turned out that almost three quarters of them had the first signs of atherosclerosis. Then it was a big surprise, because the most obvious manifestation of atherosclerosis — a heart attack in men — in most cases occurs after fifty. Similar studies of soldiers who died in the 1970s in the Vietnam War showed early signs of atherosclerosis in half of all cases, and among those who died after 2000 in the Iraq war, signs of atherosclerosis were found only in a quarter of cases. The conclusion that can be drawn on the basis of these data, despite their terrifying background, is nevertheless very positive. Obviously, atherosclerosis is less common now, and our cardiovascular system is in better condition than ever before. Maybe because they started smoking less? And shouldn't we smoke even less? Or is the reason here that we are eating better? And then what could be considered the best diet? Or are there other factors that we could influence to eradicate atherosclerosis or at least delay it as much as possible? No one knows for sure, but it is indisputable that the preventive approach — the desire to avoid risk factors — has helped significantly improve the functioning of the cardiovascular system.

It is to prevention that we owe the fact that atherosclerosis is less common now than before. And first of all, the development of medical and technical means has led to the fact that the fatal consequences of cardiovascular diseases have clearly declined. A blood vessel that has narrowed due to atherosclerosis may suddenly become clogged. A blood clot forms at the site of narrowing, which can result in a heart attack or stroke. Therefore, it is necessary to clear the vessel as soon as possible with the help of blood clot-dissolving medications in order to prevent accumulating damage due to the cessation of oxygen access. Less than fifty years have passed since a heart attack could do nothing but reduce severe chest pain with morphine. Then all that remained was to wait. Many patients died because the heart failed. The heart, working as a pump, stops due to a rhythm disturbance. In the 1960s and 1970s, the first cardiology departments were opened in hospitals to monitor patients with the first signs of a heart attack, when the risk of cardiac arrhythmias is greatest. Cardiac arrhythmia, fibrillation, can be stopped with an electroshock defibrillator. At first it was a heroic deed, but now it has become one of the most common procedures in the whole world, and defibrillators are hanging on the wall in every shopping center and at every train station. As soon as the defibrillator is applied to the patient's body, the device immediately "feels" what is happening at the moment, and "knows" exactly when the electric shock should be done. Miniature implantable defibrillators have also been developed and used for patients with recurrent unpredictable cardiac arrhythmias.

One of the possible positions of the defibrillator in relation to the heart // wikimedia.org

Over the past 25 years, medical technology has stepped far ahead. So why delay the intervention until the blockage of the blood vessel leads to the death of the heart tissue? Now the ambulance delivers heart patients no longer to the intensive care unit of cardiovascular diseases, but directly to the laboratory of catheter examination of the heart. There, a probe with mini-instruments is inserted into the femoral artery in the inguinal region of the patient, which reaches the coronary artery. In most cases, the formed thrombus can be removed, the narrowing of the vessel is expanded and the blood flow is fully restored. For the majority of patients taken to the hospital with a heart attack, the risk of premature death has decreased to several percent.

In just a few decades, the prognosis after a heart attack has improved strikingly thanks to medical and technical innovations. In the Netherlands, the risk of having a heart attack in middle age decreased by 80-90%.

About the author:
Rudi Westendorp is a professor of gerontology at Leiden University, director of the Leiden Academy of Vital Activity and Aging.

Portal "Eternal youth" http://vechnayamolodost.ru  12.05.2017

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