About 27 million of people suffer from Alzheimer’s disease. According to doctors, this value will be increased thrice by 2040. As a man ages, the risk for Alzheimer’s disease or dementia of the Alzheimer type is increasing. Thus, signs of this disease are displayed in about 20 percent of people aged 75 to 84, and in over 40 percent of those who are 85 years old.
The disease name was in honor of Alois Alzheimer, a doctor, who was the first to describe the clinical picture in his female patient with the signs typical of senile dementia though she was only 50. According to postmortem examination, she had degenerative changes in the cerebral cortex.
Consequently, similar histopathological findings were also seen in cases when the disease was manifested in much later years. This was a revolution in views on the nature of senile dementia as previously the disease was thought to be the result of atherosclerotic damage to brain vessels.
It should be stressed that the degenerative processes that occur due to Alzheimer's may begin years or even decades before its first clinical manifestations.
In the early stages of Alzheimer's disease, patients usually have a rapid decline in memory. Memory impairment conforms to the so-called Ribot’s Law: there is a time gradient in retrograde amnesia, so that recent memories are more likely to be lost than the more remote memories.
Some patients remain critical about the existing disorders for a long time. So, they feel anxious and distracted.
As the disease progresses, people experience more long-term memory loss. They can’t remember the date of their birth and names of their family members. Disturbances in memory are frequently replaced by distorted memories (confabulations). Critical perception of own condition is gradually lost.
Moreover, people with dementia of the Alzheimer type suffer from self-obsession, grumbling, suspiciousness and proneness to conflict which are markers of senile personality remodeling.Subsequently, delusion of detriment can be developed. The patient believes that family members and neighbors are trying to steal their possessions, or wish him to be dead.
Besides, other behavioral disturbances can develop such as unwelcome sexual behavior, abnormal eating with longing for sugary food, fugue state, and bustling activity (pacing, rearrangement of things, etc.).
In the severe stage of dementia, behavioral disturbances become less intense due to extremely declined mental function. The patients suffer from apathy and feel no hunger or thirst. Later movement disturbances develop, they show difficulties walking and chewing. The causes of death are concurrent diseases or conditions developed as a result of being immobile.
Dementia in Alzheimer’s disease is always diagnosed on the basis of the clinical status. The diagnosis is never definite.
A diagnosis can be made based on medical history, patient’s examination, estimation of common physical state, results of a psychological testing and laboratory research, interview with relatives and caregivers. Computed or magnetic resonance imaging are required to confirm the diagnosis. Modern methods of tomography detect signs of Alzheimer’s disease in the early stages. However, differential diagnosis between Alzheimer's disease and vascular dementia is difficult. Thus, the final diagnosis is often possible only on the basis of histological examination of post mortem brain tissue.
The goal of treatment of dementia of the Alzheimer type is to slow down the disease progression and decrease the severity of symptoms. It must be a combination therapy. Apart from anti-dementia drugs, drugs to treat concurrent diseases (hypertensive disease, atherosclerosis, diabetes mellitus, obesity, etc.) are used.
Anti-dementia drugs such as NMDA receptor antagonists and anticholinesterase drugs demonstrating significant effectiveness related to decreased intensity of dementia symptoms and slow disease progression form the background therapy of dementia of the Alzheimer type. In addition to that, neurotrophic drugs, ginkgo biloba extracts, cholinergic agents, etc. can be used as adjunctive therapy. However, further studies are required to confirm their effectiveness.
Obesity, high blood pressure, high cholesterol and blood sugar level leading to metabolic and vascular disturbances are factors for dementia of the Alzheimer type. Preventive measures include physical and mental activity, healthy eating and healthy lifestyle.
N. M. Zalutskaya
Doctor of Medical Sciences, St. Petersburg Psychoneurological Research Institute bearing today the name of V. M. Bekhterev
