Alzheimer's disease

Alzheimer's disease (AD) is a neurodegenerative disorder that causes cognitive impairment and behavioral disorders. It is characterized, in its typical form, by a loss of memory and other mental abilities that worsen as different areas of the brain atrophy. It is the most common form of dementia, affecting more than 32 million people worldwide.

The exact causes of Alzheimer's disease are unknown, although research has shown the presence of neuronal damage, with loss of connections and cell death.

The development of AD appears to be triggered by a combination of genetic and environmental factors that affect the brain over time. There are also cases of familial Alzheimer's disease, caused by point mutations, but they account for less than 1% of the total. Among the most important risk factors, the following stand out:

• Age: this is the most important risk factor, with a significant increase in cases after the age of 65.
• Family history: the risk of developing Alzheimer's disease increases if there is a first-degree relative affected. The APOE4 gene is the most studied.
• Down syndrome. Many people affected by Down syndrome develop Alzheimer's disease in adulthood, probably due to the presence of three copies of chromosome 21.
• The incidence is slightly higher in women than in men.
• Presence of mild cognitive impairment.
• Head trauma.
• Cardiovascular disease.