Alzheimer’s disease
Alzheimer`s disease is a degenerative brain disease characterized by progressing loss of intellect. The disease first described in1907 by German psychiatrist and neuropathologist Alois Alzheimer is one of the most common forms of acquired dementia. Only in the USA more than 1,5 million people suffer from Alzheimer`s disease. 30 % out of total number of 1,3 million aged in the US nursing homes make up Alzheimer`s patients.
This disease affects people independently of their nationality or socio-economic status. The youngest Alzheimer`s patent known was 28 years old, though the disease usually affects people above 40. Though very often Alzheimer`s diseases goes unrecognized, it is the fourth leading cause of death: in the US more than 100 thousand people die of Alzheimer`s disease every year.
Alzheimer’s disease was first described in patients under 65 years old; that is why earlier it was called presenile dementia. It was also wrongly considered as manifestation of aging or brain vessel sclerosis. In truth the disease is associated with degeneration of nerve cells (neurons) rather than with the affection of blood vessels.
The symptoms of Alzheimer`s disease may vary from person to person and from stage to stage. Alzheimer’s symptoms include: memory and attention impairment, thought disorder, cognition disintegration, disorientation in time and space, speech impairment, communication disorder, personality disintegration. The symptoms of dementia gradually progress leading to full inability of the patient of self-service. The process of disintegration of the psyche may last several years causing a lot of sufferings to the patient and his family.
Diagnosing Alzheimer`s.
There is no such a test which could help diagnose Alzheimer`s disease accurately. That is why the doctor should exclude other diseases causing dementia symptoms too, especially those ones which are curable, i.e. benign tumors, injuries, infections, metabolism disorders, medicine overdose and mental disorders such as depression or anxiety syndrome. Even after exclusion of other diseases the diagnose of Alzheimer’s disease is still considered hypothetical. It could only be confirmed after post-mortem microscopic examination of brain tissue. Rarely this type of examination is applied to live people. For this purpose biopsy is done (a small sample of brain tissue is removed for examination).
Changes in brain confirming the diagnose of Alzheimer`s disease are usually found in outer layer of the brain (cortex) and hippocampus, which lays deep in the hemispheres and plays an important role in the memory processes. Microscopic examination reveals neurofibrillar tangles and neuritic plaques in these region of brain of Alzheimer`s patients. The tangles consist of pathologically changed neurons containing anomalous proteins. Plaques represent are extracellular deposits of amyloid (protein and carbohydrate complexes) in the gray matter of the brain. The greater the number of tangles and plaques in the brain the more evident the intellectual disorders are.
Biochemical researches show that Alzheimer`s disease cause considerable reduction in acetyltransferase rate in brain – a ferment necessary for acetylcholine synthesis. The latter is a neurotransmitter, i.e. a substance transmitting stimulation from one cell to another and participating in memory processes.
The treatment of Alzheimer`s disease.
The disease is incurable. Tacrine is a medicine that can only suspend or decelerate the progression of the disease. That is why the treatment generally carries symptomatic nature. The patients and their families are usually helped to adjust themselves to the disease. It is important to make the patient lead an active life. In case of delirium, excitation or other behavioral changes medical therapy is recommended.
The cause of Alzheimer`s disease is yet unknown. Presently many researches are carried out in order to determine the role of viral infections, heredity, pathological immune responses, environmental factors and toxic agents in the development of the disease.