Alzheimer's dementia
Luciana Christante de Mello<o:p</o:p





<o:p</o:p What is it? <o:p</o:p It is a brain degenerative condition described by the first time in 1910 by German physician Alois Alzheimer. <o:p</o:p Dementias are characterized, in general, by memory troubles associated with logical reasoning, spatial orientation and affectivity, language and other cognitive functions impairments. These disturbances are present in Alzeihmer's disease, but what characterizes this condition in particular are the anatomical changes in the patient's brain. There is brain tissue atrophy and decrease of  encephalic volume. However, these changes, do not come suddenly, rather, they progress slowly, affecting people who are 60 years old or more. <o:p</o:p According to the  Associação Internacional para Doença de Alzheimer  (International Association for Alzheimer's Disease) (that joins some 50 associations from different countries), there are approximately 18 million people who suffer from dementia all over the world; Alzheimer's Dementia constitutes about a third of all cases (that is, some 12 million patients). In developed countries, the prevalence of the condition is about 3% among people aged 60 years old or more, and although we lack data about developing countries, it is estimated that the prevalence is about the same. Several institutions have been promoting the divulgation and awareness, as well as sponsoring and stimulating new research on this condition, given the alarming increase of the aged population all over the world, which is more noticeable in the developing countries.
 
  <o:p</o:p Mind Mystery <o:p</o:p Alzheimer's Dementia constitutes a great challenge to  neurologists and a vast range of  researchers who study the disease. Despite being described at the beginning of the 20th century, we enter the third millenium without any known preventive measure, no effective treatment much less a cure. Despite the hardly optimistic scenario, a lot has been accomplished regarding patient care, family psychological support and social intervention in order to improve the quality of life of the patient and his/her family.
  <o:p</o:p What do we know already? <o:p</o:p Some aspects of Alzeihmer's Dementia are known, even if not yet fully understood.  Familial inheritance is one of them. We know that there is higher risk of developing the disease in case a patient has a brother/sister, parent or relative affected; however, this risk is only slightly higher compared to a person without affected relatives. The concordance between twins (monozygotic and dizygotic)  is around 40%, indicating that other non-genetic factors or a complex type of inheritance. However, a relevant fact puzzles the scientists: patients with Down Syndrome (resulting from an abnormality in chromosome 21) present a much higher risk of Alzheimer Dementia when they reach the age of 35. Down Syndrome has a inheritance pattern that has been exhaustively studied and this may shed some lights on Alzheimer's disease; several researches are investigating the relationship between both conditions and chromosomal abnormalities. <o:p</o:p Although there is no definitive treatment, diagnosis has been done at earlier stages and drugs and medicine can be prescribed to alleviate the symptoms. Earlier diagnosis and improvements in patient care has increase the survival of affected people. Presently, patients live over, in average, from 6 to 8 years after being diagnosed. Differences between men and women, both in terms of survival as well as prevalence, do not seem to prevail in this condition.
 
  <o:p</o:p Disease evolution <o:p</o:p As mentioned earlier, Alzheimer Dementia is a progressive disease and the first signs of the symptoms appear more frequently after 60 years of age, although in a few cases it can manifest earlier. At first, the most evident symptom is intellectual deterioration. There are no cases of symptoms remission and periods of plateau stabilization are extremely rare.  In other words, once the first symptoms manifest themselves, the course of the disease is progressive and continuous in all patients. The clinical evolution of the disease can be divided into three stages: <o:p</o:p Stage I (first 3 years): <o:p</o:p

The patient can feel "at loss" in the home environment and although he/she manages to cope with routine tasks,  there are difficulties to deal with new challenges.
Indifference, irritability or distrust, sometimes, can be among the first symptoms. In the first stage of the disease, there is no significant changes from the neurological point of view, except for a slight hipometabolism in a specific area of the brain (posterior parietal lobes).
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Stage II (from 2 to 10 years) <o:p</o:p

Urinary incontinence can occur occasionally. Patient becomes increasingly indifferent to whatever surrounds him/her.  In this stage, neurological changes are more visible, the electroencephalogram  (EEG) pattern is altered, cerebral ventricle begin to expand and  the sulcus widen up. Metabolism under normal is observed in posterior parietal regions and also in the frontal region of the brain.
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Stage III (from 8  to 12 years) <o:p</o:p

In this last stage the dilatation of ventricle and the widening of sulcus are more evident, as well as hipometabolism in parietal and frontal areas of the patient's brain.
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Other less severe disturbances are present in the evolution of the disease, such as: <o:p</o:p

Pacients frequently died due to pneumonia, urinary infections or some other problem derived from a deteriorated health. The time of life following diagnosis, as already mentioned, is in average, from 6 to 8 years, although it can range from 2 to 20 years. The patients who express the disease at a later age, frequently died by others causes, before the final stages are reached.
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Treatament
 

Treatment for Alzheimer Dementia is based upon the symptoms shown by the patient. Depression, irritability, and agitation can be soothe by means of psychiatric medicines.
The patient's environment can both improve or worsen his clinical condition. A series of changes in the domestic settings are necessary to deal with the affected person.  Awareness and collaboration of family members are fundamentally important and frequently, especially at the terminal stages, professional assistance is needed. Many members of the household experience a great anxiety and deep sorrow as they see their beloved ones ever more alienated, dependent and incapable. Studies show that these family members ( in general, daughters and sons, husband and wives) suffer from chronic stress and show an increased risk of depression.  In this sense, as the disease progress and the care increases, the work of a trained professional such as a nurse can improve not only patient life but also of all the family.  Becoming an in-patient is recommended only at the final stage of the disease, given the great family stress and the need for intensive care.
 
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The search for cure <o:p</o:p To be able to cure Alzheimer's Dementia, scientists will have to understand  better the origins of the disease. Although there are many trails, we lack conclusive results; nevertheless, researches on Alzheimer are fast paced.  There are at least five different theories which have been investigated and up to now cannot be accepted or rejected categorically. They are: <o:p</o:p Chemical theories: it would involve the participation of neuronal growth factor, of acetylcholine (a neurotransmitter) and toxic factor such as aluminum and mercury; <o:p</o:p Genetic Theory: it would involve the participation of genes located at chromosomes 14, 19 and 21. <o:p</o:p Auto-immune Theory: it would involve the production of antibodies which would cause damage to the brain. <o:p</o:p Viral Infection Theory: it would involve a possible viral  infection during some stage of patient's life. <o:p</o:p Brain Vascular Theory: it would involve a decrease in brain blood flux resulting from changes in brain's arteries.
 
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