Alzheimer’s disease
Alzheimer’s disease is a neurodegenerative disease, the characteristic features of which are memory disorder, confusion, impaired ability to understand what has been said and speak, aggressiveness and irritability. At first, doctors believed that Alzheimer’s disease was an early form of senile dementia. However, starting in the 70s, these two pathologies began to be distinguished, since Alzheimer’s disease is often found in patients under 65 years of age.
The content of the article:
Etiology and pathogenesis of Alzheimer’s disease
Symptoms of Alzheimer’s disease
Diagnosis of Alzheimer’s disease
Treatment of Alzheimer’s disease
Prognosis and prevention of Alzheimer’s disease
Alzheimer’s disease
To date, this disease is considered the most common dementia, as it accounts for about 35-45% of cases of dementia. At the same time, if at first the pathology was considered as rare, today it has already crossed the epidemiological threshold. According to WHO, about 26.6 million people suffer from this disease in the world. By 2050, this indicator may increase fourfold. The average life expectancy of patients is on average 7 years. To date, Alzheimer’s disease is among the five most dangerous medical and social problems for humanity.
Etiology and pathogenesis of Alzheimer’s disease
The exact causes of the disease have not yet been established. Several theories have been put forward in the course of research, but none is generally accepted. To date, doctors can only talk about the genetic disposition to this disease and the factors of its development.
Genetic predisposition
Alzheimer’s disease is considered a multifactorial disease, the leading role in the development of which is genetic defects. Scientists have also identified cases of familial forms of pathology, which are usually extremely rare and manifest in patients younger than 65 years. Familial forms of the disease are transmitted by autosomal dominant type. Namely, this mechanism of disease development is characterized by the blocking of a normal gene by a pathological gene that the newborn received from a sick parent. The probability of transmission of a pathological gene is 50%.
Scientists have discovered three pathological genes that can cause the disease. Most often, Alzheimer’s disease occurs in patients who have a defect in the gene located on chromosome 14. It is proved that of all cases of familial etiology of the disease, this defect is considered the most common (60-70% of all cases of the disease). Also, the disease can occur due to defects in chromosomes 1 and 21.
Risk factors for Alzheimer’s disease
Scientists have identified a number of factors that can lead to the occurrence of the disease. All these factors can be divided into two groups: congenital or acquired due to the anatomical and physiological characteristics of the patient’s body, as well as acquired, which can be corrected.
The first group of factors includes the following:
the presence of a history of serious traumatic brain injuries;
old age;
previously suffered severe stresses;
lack of higher education;
psychological shocks;
low intellectual activity.
The group of factors that can be partially corrected includes pathologies leading to oxygen deficiency in the brain. The treatment of these pathologies will be the prevention of Alzheimer’s disease. Among these factors are the following:
diabetes mellitus;
an increase in the level of lipids in the blood;
elevated blood pressure (blood pressure);
oxygen deficiency caused by pathologies of the blood system, respiratory and cardiovascular systems;
increased concentration of amino acids homocysteine in blood plasma;
atherosclerosis of the vessels of the brain, neck and head.
It is also possible to identify another group of risk factors, from which, if desired, you can completely get rid of by reconsidering your views on lifestyle. Such factors include addiction to coffee, sedentary lifestyle, obesity, low intellectual activity.
Symptoms of Alzheimer’s disease
As a result of research, it was found that the first degenerative signs of Alzheimer’s disease in the brain appear 15-20 years before the manifestation of early symptoms of pathology. Most patients do not notice the early clinical symptoms of pathology, believing that a decrease in mental abilities occurs due to aging. That is why it is usually possible to detect the disease at the later stages of its development.
The modern classification of the stages of the disease provides for the following stages of its development:
preclinical stage (pre-dementia), which is not characterized by the appearance of any symptoms;
stage of minor disorders (patients complain of weakening of mental abilities and memory loss);
moderate dementia (it is at this stage that more noticeable symptoms appear and a diagnosis is most often made);
severe dementia.
Pre – dementia
This stage of the disease is not characterized by any pronounced disorders. Some patients may experience subtle cognitive difficulties. Usually, at least 7-8 years pass from the beginning of this stage to the appearance of more pronounced symptoms of the disease. Among the most common disorders of this period of the disease are memory disorders (the patient is unable to recall recent events), difficulties with memorization. In addition, the patient gradually acquires an inability to concentrate on anything, feels difficulties with planning and abstract thinking. Usually, all these disorders are perceived by the patient and his relatives as a result of aging.
Early dementia
One of the first pronounced symptoms of the disease is memory impairment. It is after the appearance of this symptom that the doctor may assume that the patient is progressing with Alzheimer’s disease. It is worth noting that pathology affects different types of memory in different ways. Short-term memory suffers most seriously. Less – episodic memory (the patient is able to recall events of his life that are distant in time), semantic memory (information learned a long time ago), implicit memory (memorized actions).
The impairment of the ability to remember is progressive. Therefore, patients do not immediately notice that due to memory problems they are forced to use diaries and notebooks much more often. Unfortunately, most patients try to hide their health problems from others, so it is possible to detect pathology only after its symptoms become more noticeable.
Gradually, the ability to remember deteriorates so much that the patient also has problems with long-term memory. Namely, he hardly remembers events that happened a long time ago. At the same time, he manages to remember only with the help of associations or leading questions. At an early stage of dementia, it can be difficult for a patient to remember the surnames and names of acquaintances, the names of the streets of his hometown. Often, the patient may also forget individual words.
At this stage of the disease, a progressive decrease in thinking abilities is also possible. However, the patient’s condition depends on the initial level of his intelligence. That is why the signal to see a doctor in some patients may be the inability to perform simple arithmetic operations without using a calculator, and for others — difficulties in solving puzzles or crosswords. Many patients at this stage of the disease lose the ability to perceive information holistically, so relatives may notice a change in their interests: for example, patients may stop reading serious literature and prefer watching movies. A decrease in intelligence leads to the fact that the patient has difficulties with orientation in space.
At an early stage of pathology, patients also experience psychoemotional instability. Namely, many patients are diagnosed with depression due to the manifestation of signs of mental distress. Many patients have increased anxiety and sleep disorders. There are also frequent crises that are similar in their manifestations to acute psychosis. Usually, anxiety increases in the evening and is accompanied by such pathological disorders as delusions and obsessions, paranoia, inability to recognize loved ones.
Such crises are usually caused by a sharp change in the usual situation. Moreover, in the early stages of the disease, patients are very vulnerable to various kinds of changes, since their brain is not able to process a large array of information due to dementia. Further progression of Alzheimer’s disease leads to complete indifference of the patient to everything that is happening.
Moderate dementia
At this stage, most patients lose the ability to write and read. In addition, oral speech deteriorates significantly, as patients begin to replace forgotten words with words close to them in sound. At the stage of moderate dementia, the patient’s ability to self-serve deteriorates: he cannot navigate in space, is unable to independently select clothes according to the weather, forgets the way home, does not remember the phone and address.
Patients need constant supervision, as they may forget to turn off the water or gas. In the later stages of the disease, the patient has urinary and fecal incontinence, so he needs to be reminded to visit the toilet.
Severe dementia
This is the last stage of the disease, at which the ability to self-care is completely lost. Therefore, patients need constant supervision: they need to be fed with a spoon, they often have urinary incontinence.
Patients also lose the ability to speak normally, their gait is disturbed, so they cannot walk without assistance. In the future, patients cannot smile, sit, hold their heads, swallow normally. The death of the patient in most cases occurs due to infection of the body against the background of its weakening and exhaustion.
Diagnosis of Alzheimer’s disease
If early symptoms of Alzheimer’s disease are detected, it is necessary to consult a neurologist for advice. If the disease is accompanied by depression and psychosis, an appointment with a psychiatrist may also be required. Among all the methods of diagnosis of the disease, the most significant place is occupied by the patient’s survey. Of course, there is no single survey methodology, since in many respects the selection depends on the severity and course of the disease in a particular patient.
Patient survey
There are a number of questions that the doctor asks the patient in any case. First of all, the neurologist is interested in whether the patient has any specific symptoms of Alzheimer’s disease: mental disorders (anxiety, hallucinations, sleep disorders, irritability, frequent episodes of bad mood), memory disorders, decreased intelligence. During the interview, the doctor is also interested in the history of the development of the disease. To do this, he is interested in the following information:
the time of manifestation of the first symptoms of pathology;
the circumstances of their appearance;
measures that the patient took to eliminate the symptoms;
dynamics of symptoms.
To establish the etiology of the disease, the doctor is also interested in the presence of concomitant diseases in the patient that could cause the development of the disease. These include:
past strokes;
violation of blood circulation in the brain in the chronic stage;
episodes of fainting;
excruciating headache;
epileptic seizures;
arterial hypertension;
diabetes mellitus;
severe anemia;
heart failure;
atherosclerosis.
During the patient’s interview, the doctor also necessarily collects information about his lifestyle, since some life circumstances could become risk factors for the appearance of the disease. In particular, the neurologist is interested in the psychological trauma of the patient, the level of his education, the type of professional activity, the presence of traumatic brain injuries, episodes of depression. For this reason, the doctor asks the patient to describe his lifestyle: the level of social, intellectual and physical activity, work and rest regime, the nature of nutrition, the presence of bad habits.
Psychological and neuropsychological tests
To make a diagnosis, the patient will also have to undergo a consultation with a psychotherapist. During the reception, the patient undergoes a series of psychological tests, with the help of which the doctor assesses the level of depression. Neuropsychological tests designed to assess cognitive functions are also of great importance in the diagnosis of the disease:
perceptions;
memory;
speeches;
intelligence;
the ability to perform purposeful actions.
Instrumental methods
In order to exclude other pathologies of the nervous system from the patient, the doctor may prescribe an EEG (electroencephalography). In addition, this method allows you to identify changes in the brain characteristic of pathology and trace their development. At the stage of pronounced clinical manifestations of the disease, the doctor prescribes a computed tomography of the brain, which allows you to detect and assess its anatomical damage. It is possible to detect the disease at an early stage after conducting a modern diagnostic technique — positron emission tomography.
Laboratory tests
Conducting laboratory tests allows you to determine risk factors that may contribute to the development of the disease. These include an increase in cholesterol, glucose and the concentration of the amino acid homocysteine in the blood. If all these indicators are normalized in time, it is possible to prevent or at least slow down the development of pathology.
Treatment of Alzheimer’s disease
When choosing a pathology treatment method, doctors must take into account its multifactorial nature. Treatment always begins with the correction of somatic metabolic disorders: normalization of the kidneys, thyroid gland, liver, respiratory and cardiovascular systems, replenishment of the lack of trace elements and vitamins.
Medications for the treatment of Alzheimer’s disease
However, if the correction of disorders did not give the desired result, the appointment of pathogenetic drugs that affect the internal mechanism of the disease is indicated. Symptomatic treatment is also recommended at all stages of pathology, the main purpose of which is to eliminate its symptoms: depression, hallucinations, anxiety.
The basis of drug treatment is the appointment of acetylcholiesterase inhibitors to patients, which have an effect on the central nervous system. As a rule, drugs from this group are taken for a long time or even for life. After the stabilization of the patient’s condition, a new course of drugs may be required in a year. However, it is premature to refuse to take inhibitors only at the late stages of pathology, since otherwise a rapid deterioration of the patient’s health is possible.
Another effective drug that is actively used to treat Alzheimer’s disease is memantine. It is able to normalize the exchange of glumamate in astrocytes, as well as prevent intoxication of nervous tissue. The drug is indicated for epilepsy and kidney disorders.
Psychological treatment of Alzheimer’s disease
Patients with Alzheimer’s disease urgently need psychological help. Psychological consultations may also be required by his relatives who take care of him. Most patients, feeling manifestations of the disease such as a decrease in intelligence and memory impairment, experience fear, confusion and anxiety.
As a result, they develop depression, which can be relieved by consulting a psychologist and taking medications. In addition to psychological assistance, the relatives of the patient should also receive very specific practical advice on caring for the patient, which would ensure his safety and comfort.
Prognosis and prevention of Alzheimer’s disease
The following recommendations will help prevent the development of Alzheimer’s disease:
it is advisable to avoid lack of sleep;
do not smoke;
limit yourself to sweets and sweet products;
do not abuse alcohol and nicotine;
control body weight.
Doctors also advise regularly checking blood sugar and blood pressure, since it is the violation of these indicators that is a risk factor for the development of pathology. Scientists have managed to establish that residents of Mediterranean countries are much less likely to suffer from senile dementia. Therefore, as a prevention of Alzheimer’s disease, a Mediterranean diet is indicated, which provides for the predominance of fresh fruits and vegetables, fish, lactic acid products, and a small amount of red wine in the diet. It is also advisable to observe the following preventive measures:
plan a normal rest and work regime;
daily walk in the fresh air;
train memory and intelligence.
