What is Alzheimer's disease?
Alzheimer's disease is one of the most common forms of dementia (60 to 70 percent of all cases). It is a progressive, degenerative, incurable brain disease. The intellectual power of the memory is constantly decreasing, and the neurons are dying in the entire brain. The sufferer is unable to perform the simplest tasks of daily life. Usually the symptoms occur after the completion of the 60th birthday. The disease is first described in 1906 by Dr. Alois Alzheimer, a German physician, as a "peculiar disease of the cerebral cortex".
Germany alone has over 1 million people living with this disease, mainly people over 70 years. The number of patients is a growing trend, since the proportion of older citizens is increasing.
The following figure shows that increases with increasing age, the frequency of the persons concerned. On the basis of this, it is more likely with 90+ years of Alzheimer's disease as excluded with 65 but it is not.
Scientists are still trying to determine the real causes of the disease. The probable causes could be genetic, environmental or health factors.
The deposition of protein breakdown products - amyloids - avert the transmission of impulses between neurons, which are essential for learning processes, orientation and memory.
One typical sign is a progressive deterioration of cognitive performance, which usually goes with a decrease of daily activities associated with behavioral problems and neuropsychological symptoms. Already many years before the first clinical symptoms become visible, plaques are formed in the brain of the individual, which consist of faulty folded beta-amyloid-(Aß)peptides. In addition to plagues, neurofibrils, which are depositing in the neurons, are characteristic (pathognomonic) for the disease.
See also: www.nia.nih.gov , www.nia.nih.gov
The underlying changes are not yet treatable. But drugs are able to delay the progression of the disease.
To date, the cause of Alzheimer's disease is not fully understood. Mutations that are considered to be triggers for the early subtypes have been found in 3 different genes. Despite of that, a relation between ApoE and the chance to come down with Alzheimer's has been recognized. The changes in all four genes contribute about 30 percent of the total genetic profile and result in especially large amounts of Aß accumulations in the brain.