Alzheimer’s disease (AD) is a progressive neurologic disorder that causes the brain to shrink (atrophy) and brain cells to die, and is the most common cause of dementia which leads to deterioration in cognitive function. Out of the approximately 50 million people worldwide with dementia, between 60-70% are estimated to have AD. The exact cause of AD is not yet fully understood, but factors like increasing age, family history, untreated depression and lifestyle factors associated with CVDs are thought to increase the risk of developing AD.

In AD, many neurons stop functioning, lose connections with other neurons because proteins build up and form abnormal structures called ‘plagues’ and ‘tangles’, and eventually nerve cells die and brain tissue is lost. As AD is a progressive disease, which means gradually, over time, more parts of the brain are damaged and more symptoms develop. At early stage of AD, the first sign is usually minor memory problems like forgetting about recent activities. However, as the condition develops, memory problems become severe and may develop further symptoms, including:

The major signs and symptoms are:

Currently, medications may temporarily improve or slow progression of symptoms. These treatments can sometimes help people with AD maximize function and maintain independence for a time. However, there is no treatment that cure AD or alters the disease process in the brain. Before the doctor can prescribe medications to AD patients or companies can sell products targeting AD patients, pre-clinical studies and drug screening are important to ensure the safety.