Diagnosis of Alzheimer’s Disease
According to ICD-10:
– decrease in memory (objectively, assessment of severity)
– loss of intellectual abilities (reduced ability to express judgment and think)
– decrease in the control of affect, stimuli, social behavior (irritability, apathy)
– destruction of higher cortical functions (aphasia, apraxia)
– minimum duration – 6 months.
– neuropsychological studies: rating scales, such as Mini Mental Status Test (MMST), DemTec, test for determining the time by the hour
– laboratory tests: in the cerebrospinal fluid (cerebrospinal fluid) an increase in tau protein, a decrease in A-beta peptide, the exclusion of syphilis of the nervous system, HIV infection, hypothyroidism, hypovitaminosis
– EEG: slow rhythm
– MRI: atrophy (primarily in the hippocampus) NINCDS-ADRDA clinical diagnostic criteria for Alzheimer’s disease (Mc Khannet al.) I.
Questionable signs of Alzheimer’s disease:
• Availability of documented (for example, according to the results of the MMST psychological test) progressive dementia syndrome with deficiencies in two or more areas of knowledge
• Continuously progressive impairment of memory and other cognitive functions.
• Lack of consciousness disorders
• Slow development of the disease between the ages of 40 and 90 years, mainly after the age of 65
• Exclusion of other diseases (brain diseases or systemic diseases) that may cause the development of dementia
Ii. Likely signs of Alzheimer’s disease:
• Progressive deterioration of specific cognitive functions, such as speech (aphasia), motor abilities (apraxia) or perception (agnosia)
• Strangeness in behavior and inability to cope with various household activities
• The presence of such diseases in family history, especially with neuropathological confirmation
• The following results of instrumental studies: cerebrospinal fluid – without pathology, EEG – without pathology or contains nonspecific changes (for example, slowing down the rhythm), an indication of brain atrophy at CT with an increase in the study of longitudinal section
III. Significant signs of Alzheimer’s disease:
• The diagnosis can be made on the basis of one dementia syndrome in the absence of other diseases that may be the cause of dementia, in the presence of the main signs of initiation, a picture of the disease or clinical course
• Also in the presence of another systemic or brain disease that is itself capable of causing dementia, but is not considered the only cause
• If, with the exclusion of other possible causes of the disease, only a progressive, severe cognitive deficit is present, it should be carefully examined.
Diagnostic criteria for Alzheimer’s disease according to ICD-10:
• presence of dementia
• Gradual onset with slowly progressive dementia
• Lack of clinical guidelines or specific examination data indicating a systemic or brain disease that could trigger dementia
• Absence of a sudden apoplectic onset or indication of a neurological focus
Important: A typical patient feels quite healthy, does not complain about forgetfulness, tries to be inconspicuous, “ordinary”, avoids answering questions, and goes to a doctor not on his own initiative. Alzheimer’s disease is a diagnosis of exclusion. It is possible to confirm the diagnosis only neurologically.
Differential diagnosis of Alzheimer’s disease
• Depressive pseudodementia: most often appears in the differential diagnosis, but does not have pathognomous signs
• Vascular dementia: undulating course, focal symptoms of damage to the nervous system; on MRI multiple microinfarcts
• Other organic brain processes leading to dementia, such as Pick’s disease, Parkinson’s disease, Creutzfeldt-Jakob disease, Huntington’s chorea, progressive paralysis, etc.
• Hydrocephalus with normal pressure
• Korsakovskiy syndrome: amnesia, confabulations, impaired oculomotor functions and gait
• Mild cognitive impairment; in case of “benign” age forgetfulness, certain “things” and “objects” are forgotten, first of all; in Alzheimer’s disease, first of all, “incidents” and “events” are forgotten.
• Drug therapy:
– antidement drugs, acetylcholinesterase blockers (galantamine, donepezil, rivastigmine) or K-methyl-O-aspartate receptor antagonist (NMDA) memantine
– in the presence of depression, antidepressants may be used.
– in a state of anxiety, confusion and sleep disorders, the use of (atypical) antipsychotics is possible
Important: Anti-dementia drugs slow down the progression of the disease, but do not cure.