Alzheimer´s Disease is a devastating neurodegenerative disease of the central nervous system without the availability of disease-modifying treatment. It is the most common cause of dementia (60-80% of cases) where most of the 100 billion nerve cells die and the brain dramatically shrinks and therefore destroys the patient's personality, intelligence and life and severely affects the patients families and their environment.
Alzheimer´s Disease is named after Dr. Alois Alzheimer. In 1906, he noticed changes in the brain tissue of a woman who had died of an unusual mental illness. Her symptoms included memory loss, language problems, and unpredictable behavior. After she died, he examined her brain and found many abnormal clumps (plaques) and tangled bundles of fibers (tangles) which are today considered as the main features of Alzheimer´s Disease.
The prime suspect of the causes of the Alzheimer´s Disease is a small protein fragment called Abeta which is overproduced and changes its structure. The misfolded Abeta can then accumulate to microscopic “plaques” considered as one of the pathological hallmarks of Alzheimer´s Disease. The other hallmark is “tangles” formed from a different protein called Tau. Together with inflammation and oxidative damage, these factors lead to catastrophic brain damage and the symptoms usually developing in three general stages:
Mild Alzheimer´s Disease
People are often diagnosed with mild Alzheimer´s Disease facing problems with memory loss and changes in other cognitive abilities. Problems can include getting lost, trouble handling money and paying bills, repeating questions, taking longer to complete normal daily tasks, poor judgment, and mood and personality changes.
Moderate Alzheimer´s Disease
In this stage, damage occurs in areas of the brain that control language, reasoning, sensory processing, and conscious thought. Memory loss and confusion increase, and people begin to have problems recognizing family and friends. They may be unable to learn new things, carry out tasks that involve multiple steps (such as getting dressed), or cope with new situations. They may have hallucinations, delusions, and paranoia, and may behave impulsively.
Severe Alzheimer´s Disease
By the final stage, plaques and tangles have spread throughout the brain and brain tissue has shrunk significantly. People with severe Alzheimer´s Disease cannot communicate and are completely dependent on others for their care. Near the end, the person may be in bed most or all of the time as the body shuts down.
Currently there is no efficient diagnostic test that detects early onset of the Alzheimer´s Disease. The disease can be definitively diagnosed only after death by linking clinical course with an examination of brain tissue and pathology in an autopsy. Currently, Alzheimer´s Disease is primarily diagnosed via a battery of cognitive tests performed by a physician. A number of novel diagnostic methods are under development, which may lead to an earlier and more accurate diagnosis. Today, the diagnostic techniques under evaluations are biophysical evaluations, biochemical evaluations of spinal fluid and blood as well as brain scans. Recent studies suggest that Alzheimer´s Disease can be detected through biomarkers in an even earlier phase - prodromal Alzheimer´s Disease, when patients face first problems with memory loss.
Early diagnosis is beneficial for several reasons. Having an early diagnosis and starting treatment in the early stages of the disease can help preserve function for months to years, even though the underlying process cannot be changed so far. Having an early diagnosis also helps families plan for the future, make living arrangements, take care of financial and legal matters, and develop support networks.