Mild cognitive impairment is a slight decrease in the cognitive functions of the patient compared to a higher premorbid level. The symptoms remain objectively invisible, but the patients themselves complain of forgetfulness, difficulty concentrating, fatigue during mental work. Diagnosis involves a pathopsychological and neuropsychological study of the intellectual sphere, a conversation with a psychiatrist, an examination by a neurologist. Treatment is aimed at eliminating the cause of cognitive disorder, includes psychocorrective classes, drug therapy, diet and daily routine.
ICD 10
F06.7 Mild cognitive impairment
General information
The word “cognitive” in Latin means “cognitive, introductory”. Thus, mild cognitive impairment (MCI) is a slight decrease in mental abilities: the ability to memorize and reproduce information, concentrate attention, solve abstract logical problems. MCI does not reach the level of mental retardation, dementia or organic amnestic syndrome. Precedes, accompanies or occurs after an infectious or organic disease. Older people are more susceptible to the disorder, with a prevalence of 10% among people over 65. Of this group, 10-15% develop symptoms of Alzheimer’s disease during the year. MCI is more often diagnosed in people with a low level of education.
Causes
Mild cognitive impairment is not a separate nosological form, but a peculiar condition that occupies an intermediate position between normal intellectual development and dementia. By origin, it is heterogeneous (polyetiological), the causes of development can be a variety of pathological processes in the central nervous system:
- Neurodegenerative diseases. The disorder is formed with senile dementia of Alzheimer’s type, Parkinson’s disease, Huntington’s chorea, dementia with Lewy bodies, progressive supranuclear paralysis. Cognitive decline precedes the appearance of the main symptoms.
- Vascular pathologies of the brain. MCI is diagnosed in patients with cerebral infarction, multiinfarction, chronic cerebral ischemia, hemorrhagic and combined vascular brain damage. Symptoms of cognitive impairment are found in the disease and in the period of consequences.
- Dysmetabolic encephalopathies. Due to metabolic disorders, insufficiency of internal organs, disorders in the functioning of the central nervous system occur. MCI is determined in hypoxic, hepatic, renal, hypoglycemic, dystyroid encephalopathy, deficiency of B vitamins and proteins, poisoning.
- Demyelinating diseases. The disorder is detected at an early stage of progressive paralysis, multiple sclerosis, progressive multifocal leukoencephalopathy. It increases in accordance with the dynamics of the underlying disease.
- Neuroinfections. Cognitive insufficiency is determined at the initial stages of HIV-associated encephalopathy, Creutzfeldt-Jakob disease. In acute and subacute meningoencephalitis, MCI unfolds as a consequence of the infectious process.
- Traumatic brain injuries. Mild cognitive impairment may be temporary or relatively persistent in the long-term period of traumatic injury. The symptoms are determined by the nature of the injury (depth, diffuseness or locality of the lesion).
- Brain tumors. The disorder occurs at the beginning of the disease. The clinical picture is determined by the localization of the neoplasm.
Pathogenesis
The pathogenetic mechanisms of MCI are diverse, depending on the leading etiological factor. In old age, the processes associated with aging have an impact: weakening of attention, focus, memory. Clinical and experimental psychological studies confirm that age-related cognitive impairment develops independently, without concomitant neuropsychiatric diseases against the background of natural aging processes of the central nervous system (age-related loss of neurons, changes in nerve fibers of the white matter and synaptic apparatus).
In 68% of cases, MCI occurs on the basis of cerebrovascular disorders, in which a decrease in the cognitive sphere is due to pathological changes in cerebral vessels, insufficiency of cerebral circulation. The second most common is degenerative brain tissue damage (atrophy). Another 13-15% of elderly and senile patients have anxiety-depressive disorders and tend to exaggerate the severity of memory disorders.
Symptoms
Clinical manifestations correspond to the state of cerebrastenia: patients are outwardly preserved, there are no gross violations of criticism and intelligence, a slight attentive-mnestic decrease is determined, fatigue is rapid. Patients complain of forgetfulness, absent-mindedness, difficulties in memorizing new material, the need to focus attention and hold it. With vascular mild cognitive disorders, behavioral and emotional disorders are observed at the onset – increased anxiety, affective instability, fussiness and absent-mindedness, mnestic symptoms manifest later. Patients with degenerative pathologies of the central nervous system primarily have problems with memory.
Patients often experience headaches, a feeling of heaviness in the head, general weakness, drowsiness, dizziness. Ailments are of a non-systemic nature, have different intensity throughout the day, in many patients they are noted in the morning and in the evening. Possible instability when walking, restless and intermittent sleep, insomnia, lack of appetite, nausea. The condition worsens after mental and physical exertion. The course of MCI depends on the underlying disease, it can be fluctuating (often with cerebrovascular shifts), progressive, turning into dementia (with atrophic processes, tumors, some infections) and regredient (after stroke, TBI, acute passing infections).
Complications
A mild cognitive disorder with a progressive course in the absence of treatment quickly leads to the development of dementia. Patients lose the ability to solve everyday tasks, need help with self-care. Socialization is disrupted – the circle of communication is narrowed, patients cannot perform professional duties, attend social events. With the fluctuating course of the disorder, patients experience difficulties during the performance of intensive mental tasks, but with the correct correction of the regime and reduction of loads, they retain their usual vital activity.
Diagnostics
The study of MCI is performed by a neurologist, psychiatrist, clinical psychologist. For diagnosis, criteria are used, defined taking into account the emphasis on memory loss, normal or borderline general state of the cognitive sphere, absence of dementia, oligophrenia and psycho-organic syndrome. Differentiation of MCI and these diseases is based on the data of clinical and psychodiagnostic examination. The following methods are used:
- Discussion. A psychiatrist and a neurologist interview the patient, finding out the anamnesis and the existing symptoms. Typical complaints of increased fatigue, difficulty remembering and concentration, general confusion. Patients whose professional activity is associated with high intellectual loads may note difficulties in formulating abstract ideas, logical conclusions.
- Psychological testing. Depending on the anamnesis data, the psychologist conducts a pathopsychological or neuropsychological examination. A slight degree of short-term memory decline, fluctuations in the dynamics of mental activity, slight instability of attention are revealed. Reducing the abstract-logical function is possible, but not necessary. The results of the samples are interpreted taking into account the age, level of education and the sphere of professional activity of the patient.
- Neurological examination. A neurologist’s examination is prescribed for the purpose of differential diagnosis and determination of the causes of MCI. Mild but persistent neurological disorders are often identified: anisoreflexia, discoordination phenomena, oculomotor insufficiency, symptoms of oral automatism. No distinct syndromes are detected.
Treatment
Therapy is aimed at preventing dementia, slowing the rate of cognitive decline, eliminating existing mnestic disorders. The main therapeutic measures – etiotropic, pathogenetic – are aimed at the cause of the disorder. They may include correction of dysmetabolic disorders, vascular changes, depression, the use of antioxidants, vasoactive, neurotransmitter, antiviral drugs, chemotherapy, surgical removal of the tumor. Common methods of therapy are:
- Psychocorrection. Systematic exercises are used to improve memory and attention: reading and retelling texts, memorizing poems, words, drawings. Classes are conducted together with a psychologist and independently. At meetings with a specialist, new techniques of memorization are mastered – the formation of semantic and situational connections, the analysis of situations and objects. Periodically, the effectiveness of classes is monitored, the set of exercises is adjusted.
- Medical treatment. The scheme of drug therapy is selected by the doctor individually. The most common drugs for the treatment of cognitive disorders are nootropics and metabolic agents.
- Correction of nutrition and daily routine. Middle-aged and elderly patients need to follow a diet with a reduced fat and salt content, with sufficient intake of antioxidants. Moderate regular exercise, full sleep, rational alternation of physical and mental stress are important. After completing your work, you need to remain socially active – visit clubs of interest, meetings with friends, etc.
Prognosis and prevention
With effective etiotropic treatment, the prognosis of MCI in most patients is favorable: the process of cognitive decline is suspended, the resulting disorders are reduced (with a regredient course of the underlying pathology). The main prevention is reduced to the prevention of vascular and atrophic processes in the brain. It is important to maintain physical activity, give up smoking and alcohol consumption, adjust nutrition by reducing the intake of fatty, smoked and salty foods, introduce a sufficient amount of vegetables, fruits, cereals, vegetable oils into the diet.
