Dementia

One of the types of dementia, affecting one in 20 people over the age of 65. It is named after the German psychiatrist and neurologist Alois Alzheimer.

There are varieties of this disease that also affect younger people. The "gray matter" of the brain is affected, leading to memory loss and progressive dementia. It is a disorder of brain processes, not of physical functions.

It is caused by the accumulation of ß-amyloid (a breakdown product of a protein, the amyloid precursor — Amyloid Precursor Protein, or APP for short), which is capable of forming fibrous structures (fibrils).

Scientists studying this disease have split into two camps: some argue for the important role of tau protein, while others — for ß-amyloid (Aß) and its varieties (Aß42, Aß40, oligomeric forms of both varieties, as well as their N-terminal modifications) in the development and course of the disease.

Three genes are known whose mutations largely explain the origin of the rare early-onset form, but the common form of Alzheimer's disease does not yet fit into a purely genetic model. APOE is currently considered the most pronounced genetic risk factor, but variations of this gene are associated with only some cases of the disease.

Prevention of Alzheimer's disease: international studies designed to assess how much a particular measure can slow down or prevent the onset of the disease often yield contradictory results.

There is still no firm evidence of the preventive effect of any of the factors considered. At the same time, epidemiological studies indicate that some modifiable factors — diet, cardiovascular disease risk, medication use, mental activity and others — are associated with the likelihood of developing the disease.