Alzheimer's disease is the most common cause of dementia. It’s a neurodegenerative disease that affects your brain. This means it damages and destroys cells in your brain over time. Eventually, people with AD lose some of their brain functions, including memory and language. Alzheimer’s disease affects approximately 24 million people worldwide. One in 10 people older than 65 has it. Nearly 1 in 3 people older than 85 has AD.

Source: Cleveland Clinic