Health and Space (UN, 1986)
In my presentation today I would like to draw your attention to the question of what space nights can teach us — and in particular lengthy flights — on deepening and expanding our medical knowledge about human beings.
Nature is not only around us, but also within us. We ourselves are a part of nature, to which we need to give thought, and which needs to be as carefully protected as the environment.
In general terms, abstractly speaking, everyone understands this. The problem — and it is a real one — lies in that fact that few of us associate this with our own health, with our own life-style.
Prevention of illness, the maintenance of good health, and an active and long life have long been regarded as the major goal of medicine. And here impressive results have been achieved. We need only recall the successful elimination of many dangerous infectious diseases.
It has now become clear that space medicine has made a valuable contribution to the expansion of medical knowledge.
Our (so-called) “patients,” astronauts, are healthy individuals whom we monitor for rather long periods of their lives. These include
the period of selection and training, the very difficult duties during space flights and during the return to earth’s gravitational pull, preparations for new launches and then the actual flight itself. During all these stages the astronauts are given thorough physical examinations and are under close medical observation.
Our knowledge of the mechanisms governing the cardiovascular system, muscle tone, movement coordination, and fluid-electrolyte metabolism has been considerably expanded. We also know a great deal more about the structure and functioning of bone tissue and of the inner ear mechanism.
It is common knowledge that among types of illnesses various diseases of the cardiovascular system play a very important role. Among these, first and foremost, coronary heart disease and hypertension with complications, primarily involving disorders in cerebral circulation, are responsible for mortality and morbidity of people in many countries. The pathology of the cardiovascular system can with good reason be called an illness of the 20th century.
This, it seems to me, is precisely why for the diagnosis and prevention of cardiovascular disease the experience of space medicine can be extremely useful.
It is known that in space flights the most significant changes occur in the cardiovascular system. These are primarily attributed to a decline in motor activity, increased nervous-emotional strain, and a shift in blood flow towards the upper part of the body due to zero gravity in blood circulation, and some other less important factors. This is why medical monitoring of the health of astronauts continues to attach great importance to a leading role for cardiovascular examinations.
It is clear that such illnesses as coronary heart disease, hypertension and a number of other circulatory diseases do not emerge without warning. They develop gradually as a result of negative conditions, so-called “risk factors.” The results of large-scale epidemiological studies have demonstrated that the basic risk factors of cardiovascular disease are a sedentary life style, nervous-emotional stress, poor nutrition (obesity), disorders of the lipid metabolism, smoking, etc.
Individual risk factors include three non-controllable ones: age, sex, and heredity. Moreover, it is known that the frequency of cardiovascular diseases increases with age, that the incidence among men is twice as high as among women, and that the probability of such illness is higher among individuals whose parents had heart attacks when they were under 50.
The most important of these factors are: genetic traits; age; a family history of cardiovascular disorders; sedentary life style; poor nutrition, and stress.
Another important risk factor accompanying the development of cardiovascular disease is poor diet.
Our human nature is ancient, but it is by no means antiquated. It should not be preserved by protecting the organism from physical or information overload, or by creating for it some kind of hothouse living conditions.
The opposite is true. Only intense, varied, harmonious and useful activity can protect our health and make our lives interesting and productive.
The experience of work with astronauts clearly shows a simple truth: regular physical examinations and the use of rational preventive procedures can maintain good health, and an enhanced capacity for work.
Space medicine, since it is by definition preventive and prophylactic, is a model for the medicine of the future.
Its methods and means of stabilizing the health of the astronauts, together with the experience and achievements of clinical medicine, already can make a significant contribution to improving the health of people throughout the world.