What is Dementia in Alzheimer’s Disease?
Dementia is a chronic or progressive brain disorder in which higher cortical functions are impaired, including memory, thinking, orientation, understanding, counting, learning ability, language and judgment. Consciousness is not darkened. Symptoms are present for at least 6 months, although a more progressive onset of dementia is possible. Long-term medication, vitamin B12 and B6 deficiencies, metabolic imbalances due to kidney and liver diseases, as well as endocrine pathology, vascular pathology, depression, infections, head injuries, alcoholism, and tumors contribute to dementia. In the diagnosis of dementia, additional symptoms, such as delirium, hallucinations, and depression, are also noted.
Causes of Dementia in Alzheimer’s Disease
The etiology of Alzheimer’s disease is similar to other dementiating processes. The genetic cause is a defect in various parts of chromosome 21 in the constriction area and lower arm; the genes of these regions control the growth of local groups of neurons. The disease is likely to be genetically heterogeneous, as recessive and dominant types of transmission are observed. The defect leads to the formation of beta-amyloid accumulations (amyloid bodies, Glenner bodies) in the posterior areas of the dominant hemisphere, which interfere with microcirculation. Deficiency of acetylcholine transferase, reduction of acetylcholine synthesis and slowing down of neuronal conductivity, as well as aluminum intoxication take part in the pathogenesis. The increase in aluminum in plasma is observed with prolonged intake of aspirin, after hemosorption and hemodialysis, as well as when living in ecologically unfavorable areas, in particular, over bauxite deposits. It is assumed that in the evolution of Alzheimer’s disease arose as a result of prion damage of 21 chromosomes by a slow infection virus, but was not selected due to the selective advantages of the affected ones, which include, in particular, the higher amount of memory characteristic of them in the early stages of ontogenesis. Reduced memory in this disease leads to sensory and social isolation, which causes secondary deprivation, and this contributes to the increase in dementia. Similarly, deprivation develops in other dementias. Atrophy of the cortex leads to compensatory hydrocephalus and expansion of the lateral ventricles. With an increase in liquor production, the severity of dementia increases. Since amyloid can accumulate around the vessels, the vascular factor is also involved in the pathogenesis. The autoimmune factor also plays a role in etiology and pathogenesis.
In one of the variants of the disease, amyloid accumulates in the occipital and parietal regions, as well as the hypothalamic nuclei (a disease with Lewy bodies). Such cases occur with hallucinatory-paranoid psychosis and epileptic seizures.
In each case of the disease, one can speak about the degree of the contribution of various factors to the etiology and pathogenesis of the disease.
Alzheimer’s disease is detected in more than half of all patients with dementia. In women, the disease is noted twice as often as in men. 5% of people over 65 are susceptible to the disease, however, the disease most often begins at age 50; described juvenile cases at the age of 28 years. It takes 4-5th place among the causes of death in the United States and Europe.
Symptoms of Dementia in Alzheimer’s Disease
The disease is more often progressed, although with the accumulation of amyloid around the vessels, paroxysmal variants associated with a combination of atrophy and vascular pathology are possible. Disease duration from 2 to 10 years. In dementia with a late onset (after 65), the degree of progression is less than in dementia with an early onset (up to 65 years). In dementia with early onset, damage to the parietal, temporal region and hypothalamic nuclei (a disease with Levi’s calves), and a more pronounced genetic predisposition are noted. Mixed, atypical options associated with combinations of vascular or traumatic and atrophic dementia.
In the initial period, prolonged and non-therapeutic neurotic states, prolonged depressive episodes, chronic paranoid states, in particular, with ideas of jealousy and damage, acute and transient psychotic disorders, are not uncommon. Already at this stage, signs of atrophy can be noted on computed tomography (CT). Primary cognitive decline is subjectively noted by the patient himself, trying to compensate for it.
In the early stages, you can notice a peculiar change in facial expression – “Alzheimer’s amazement”, in which the eyes are wide open, mimicry of surprise, blinking rare. Orientation in an unfamiliar place deteriorates. There are difficulties in the account, the letter. In general, it seems to reduce the success of social functioning.
The main symptoms of the first – manifest stage are progressive memory disorder and the individual’s reaction to cognitive deficits in the form of depression, irritability, impulsivity. Behavior regressiveness is noted: negligence, frequent gathering “on the road”, stereotype, rigidity. In the future, memory disorders are no longer recognized. Amnesia extends to habitual actions, patients forget to shave, dress, wash. Nevertheless, the last violated the professional memory. On the EEG can be noted as a paroxysmal activity, and lowering the voltage above the focus of atrophy. Patients may complain of headaches, dizziness and nausea, which is a symptom of hydrocephalus. Progressively lose weight in a short period of time with a safe and even increased appetite.
When talking with the patient noticeable disturbances of attention, unstable fixation of the gaze, stereotypical pickup movements. Sometimes the disease manifests acutely in the form of amnestic disorientation. Leaving home, patients cannot find it, forget their last name, year of birth, cannot predict the consequences of their actions. The period of disorientation is replaced by relative memory preservation. Acute manifestation and paroxysmal flow indicates the presence of a vascular component.
In the second stage, apraxia, acalculia, agraphia, aphasia, and alexia join the amnesic disorders. Patients confuse the right and left side, can not name part of the body. There is an autoagnosis, and they cease to recognize themselves in the mirror. Surprisingly examining themselves, they touch the face. The handwriting and character of the painting is changing. Epileptic seizures and short-term episodes of psychosis are possible. Joining somatic pathology, for example, pneumonia, which can cause delirium. Muscle stiffness, stiffness are increasing, parkinsonian manifestations are possible. In the speech of perseveration, in bed, patients are stereotypically covered with the head or make “obscharyvayuschie” movement.
Dementia in early-onset Alzheimer’s disease (F00.0).
This option is characterized by the presence of common signs of Alzheimer’s disease, the onset of the disease before the age of 65, the rapid progression of symptoms. In the family history are noted: atrophic dementia, Down syndrome, lymphoidosis.
Dementia in late-onset Alzheimer’s disease (F00.1).
For this variant, common signs of Alzheimer’s disease occur at the beginning after 65 years or, more often, after 75 years, and slow progression with impaired memory, often according to Ribot’s law.
Dementia in Alzheimer’s disease is atypical or mixed type (F00.2).
These options include combinations of Alzheimer’s disease and vascular dementia, as well as atypical variants of the disease. It is close to the Heckebushe-Geyer-Geimanovich syndrome described in the Russian literature. The course of the disease is intermittent, with an increasing cognitive deficit. This group also includes diffuse disease with Lewy bodies. At the initial stage, it is characterized by agitation, verbal hallucinosis, persecution delusions, orthostatic hypotension, dysphagia, and sometimes parkinsonism. Further develop amnesic violations.
Diagnosis of Dementia in Alzheimer’s Disease
The diagnosis requires signs of dementia, that is, decreased memory, other cognitive functions, reduced control over emotions, impulses, as well as objective confirmation of atrophy on CT, EEG or neurological examination. At CT scan, there is an expansion of the lateral ventricles from the side of atrophy, which can lead to a shift of the median brain structures towards the atrophic focus, thinning of the furrows and expansion of the subarachnoid spaces. The focus of atrophy itself is only slightly higher than the density of the surrounding brain tissue.
Criteria for the diagnosis of Alzheimer’s disease: the presence of criteria for dementia, a gradual onset of slowly advancing dementia, lack of data from clinical or special studies in favor of another systemic or brain disease; lack of focal cerebral symptoms in the early stages of dementia.
Dementia in Alzheimer’s disease can be combined with vascular dementia, with such a combination is likely a wave-like course of the disease (Geyer-Heckebushe-Geimanovich syndrome).
Alzheimer’s disease should be differentiated from affective disorders, especially often with prolonged depressive episodes starting at a later age. Depression may be accompanied by a pseudodementia clinic described by Wernicke. In addition, prolonged depression can lead to cognitive deficits as a result of secondary deprivation. For the distinction have anamnestic information, the data of objective research methods. In depressed patients, typical daily mood swings and relative success in the evening are more frequent, and attention has not been disturbed. In depressed patients mimicry, Veraghuta fold, lowered corners of the mouth are noted, and there is no confusion and rare blinking characteristic of Alzheimer’s disease. When depression is also not marked gestural stereotypy. With depression, as with Alzheimer’s disease, progressive involution is noted, including decreased skin turgor, dull eyes, increased fragility of the nails and hair, but these disorders in brain atrophy are more often ahead of psychopathological disorders, and in depression they are noted with a long duration of decreased mood. Weight loss with depression is accompanied by a decrease in appetite, and in Alzheimer’s disease, appetite is not only not reduced, but can also increase. Patients with depressions react more clearly to antidepressants by increasing activity, but in Alzheimer’s disease, they can increase sustainability and astenisation, giving the impression of overloading patients.
In the 19th century, vesanic dementia, which Ganser K. in 1898 called “minimal brain weakness,” was first described by Weknicke, called it pseudo-dementia, although later these clinical manifestations were referred to as dissociative (hysterical). The author, however, suggested that it occupies an intermediate place between organic and affective disorders. For her, according to the researcher, were characterized by a periodic course, a decrease in mood, answers by and the background of organic disorders. In subsequent years of clinical observations, it became clear that depression always contains a cognitive deficit, especially if it lasts more than three months and begins after the age of 40 years. R. Abrams in 1997 in his review of electroconvulsive therapy of depression indicates Rip Van Winckle syndrome, which was first described in a 72-year-old patient. At the age of 58, he was diagnosed with Alzheimer’s dementia, but then, after 14 years, he was given a course of electroconvulsive therapy, after which the patient fully recovered. Throughout the entire time of observation, he answered the questions concisely, did not concentrate attention, he had mask-like facial expressions, he was indifferent to contact and did not react to his own cognitive deficit. Price T.R., McAlister T.W. in 1989, 22 cases of depressions were recorded, beginning at an average age of 64.2 years, 6 men and 16 women, the duration of the disease was from 12 to 14 years, which proceeded with a clinic that masks dementia. Among other clinical components in the affect structure, obsessions, depressive stupor, parkinsonism, muscular rigidity, thrombophlebitis and tachycardia, thalamic headaches were included. The authors for the first time suggested starting treatment for dementia after the age of 50 with electric shock, isoflurane, drug therapy or tricyclic antidepressants. However, they did not offer sufficiently convincing criteria for distinguishing between depression and dementia after the age of 50, and suggested that long-lasting depression at a late age in fact only predates dementias, since they later began anyway. Cromwell R.L., Snyder C.R. in 1993, they found that when treating patients with schizophrenia after the age of 50, an neuroleptic syndrome is formed, which is typologically similar to the clinic of prolonged anesthetic depression and “mild” dementias, they also found that this phenomenon is associated with organic changes in the pale ball and subcortical structures. These patients were taciturn, hypomimic, inhibited, and showed decreased attention and learning.
The states of amnesic disorientation and psychosis in Alzheimer’s disease have to be differentiated from asthenic confusion and confusion, cognitive deficits in other organic disorders, for example, after craniocerebral injuries, stroke, vitamin deficiencies, endocrine diseases. These conditions are more often transient, accompanied by impaired consciousness, and focal neurological symptoms are present in the clinic. Decisive for the differential diagnosis are data CT or nuclear magnetic resonance studies.
Schizophrenia, which occurs on an organic background, at a stage of defect at a later age, can also resemble Alzheimer’s dementia. The differential diagnosis is especially difficult when there are no anamnestic data. However, the presence of formal thinking disorders in patients with schizophrenia, for example, paralogical, including autistic, symbolic, identifying, contrasts with the amnesic syndrome. Psychological research in patients with schizophrenia reveals reliance on latent signs, diversity and judgments based on their own attitudes, the presence of a cognitive deficit is not typical, although semantic aphasia is possible. It is more difficult to make a differential diagnosis in the presence of mutism. Emotional-volitional disorders characteristic of schizophrenia are characterized by coldness, loss of social connections and regression of behavior without cognitive deficit adequate for such regression.
Often, dementia in Alzheimer’s disease differentiates with dementia in Pick’s disease. At distant stages, these disorders are not clinically distinguishable, but if Alzheimer’s disease begins with memory disorders, then Pick’s illness is caused by behavioral disorders that are caused by lesions of the frontal areas.
Apraxia in Alzheimer’s disease has to be differentiated from similar disorders in corticoregeneral degeneration, but in the latter it is combined with a mask-like face, rigidity and tremor of the extremities, and loss of the ability for subtle hand movements. That is, it is not so much apraxia as dyspraxia.
Mnestic disorders in Alzheimer’s disease differentiate from normotensive hydrocephalus (Hakim-Adams disease). Along with progressive changes in memory, usually also at a later age, it is characterized by slowness, gait imbalance, and urinary incontinence at a late stage.
Dementia Treatment for Alzheimer’s Disease
The treatment should limit the use of tranquilizers and neuroleptics due to the rapid development of intoxication phenomena. Usually, their use is possible during periods of acute psychosis and in minimal doses. The focus is on the prevention of secondary deprivation with the help of special instructions from relatives, cognitive deficits, anti-Parkinsonian, and vascular agents. Certain place belongs to the methods of reducing the pressure of cerebrospinal fluid, hormonal drugs.
Secondary deprivation is overcome by an increase in the sensory enrichment of the environment, that is, relatives should be convinced of the need to “teach the patient again.” Persistent repetition and memorization of the forgotten should become the rule; constant communication and patient employment, which are planned for the whole day, are important. Relatives under the influence of patient observation may develop a feeling of guilt, neurotic states.
Nootropics and cholinesterase inhibitors are among the means of cognitive deficiency, this therapy should be constant and in high doses, megavitamin therapy (megadoses of vitamins B5, B12, B2, E). The most proven agents among cholinesterase inhibitors are tacrine, donepezil, rivastigmine, physostigmine and galantamine. Among the anti-parkinsonian drugs, jumex is most effective. Periodic therapy with small doses of angiovazine and cavinton (sermion) affects the vascular component. The most effective means against CSF is shunting (cranio-peritoneal, cranio-fascial, cranio-lymphatic). The combination of shunting with active learning and nootropics makes it possible to significantly slow down the dementiating process. The means affecting the processes of short-term and long-term memory include somatotropin, prephysone and oxytocin. Short courses of these drugs are especially indicated in cases of a combination of atrophy with accelerated involution.