Signs and symptoms of dementia result when once-healthy neurons, or nerve cells, in the brain stop working, lose connections with other brain cells, and die. While everyone loses some neurons as they age, people with dementia experience far greater loss.
The symptoms of dementia can vary and may include:
Experiencing memory loss, poor judgment, and confusion
Difficulty speaking, understanding and expressing thoughts, or reading and writing
Wandering and getting lost in a familiar neighborhood
Trouble handling money responsibly and paying bills
Repeating questions
Using unusual words to refer to familiar objects
Taking longer to complete normal daily tasks
Losing interest in normal daily activities or events
Hallucinating or experiencing delusions or paranoia
Acting impulsively
Not caring about other people’s feelings
Losing balance and problems with movement
People with intellectual and developmental disabilities can also develop dementia as they age, and recognizing their symptoms can be particularly difficult. It’s important to consider a person’s current abilities and to monitor for changes over time that could signal dementia.
The causes of Alzheimer’s and related dementias can vary, depending on the types of brain changes that may be taking place. While research has found that some changes in the brain are linked to certain forms of dementia, in most cases, the underlying causes are unknown. Rare genetic mutations may cause dementia in a relatively small number of people.
Although there is no proven prevention, in general, leading a healthy lifestyle may help reduce risk factors that have been associated with these diseases.
Types of dementia include:
Alzheimer’s disease, the most common dementia diagnosis among older adults. It is caused by changes in the brain, including abnormal buildups of proteins, known as amyloid plaques and tau tangles.
Frontotemporal dementia, a rare form of dementia that tends to occur in people younger than 60. It is associated with abnormal amounts or forms of the proteins tau and TDP-43.
Lewy body dementia, a form of dementia caused by abnormal deposits of the protein alpha-synuclein, called Lewy bodies.
Vascular dementia, a form of dementia caused by conditions that damage blood vessels in the brain or interrupt the flow of blood and oxygen to the brain.
Mixed dementia, a combination of two or more types of dementia. For example, through autopsy studies involving older adults who had dementia, researchers have identified that many people had a combination of brain changes associated with different forms of dementia.
Scientists are investigating how the underlying disease processes in different forms of dementia start and influence each other. They also continue to explore the variety of disorders and disease processes that contribute to dementia. For example, based on autopsy studies, researchers recently characterized another form of dementia, known as LATE. Further knowledge gains in the underlying causes of dementia will help researchers better understand these conditions and develop more personalized prevention and treatment strategies.
