What are the signs and symptoms of dementia?

Signs and symptoms of dementia result when once-healthy neurons (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 signs and symptoms can vary depending on the type 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 in these cases, 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.

What causes dementia?

Dementia is the result of changes in certain brain regions that cause neurons (nerve cells) and their connections to stop working properly. Researchers have connected changes in the brain to certain forms of dementia and are investigating why these changes happen in some people but not others. For a small number of people, rare genetic variants that cause dementia have been identified.

Although we don’t yet know for certain what, if anything, can prevent dementia, in general, leading a healthy lifestyle may help reduce risk factors.

What are the different types of dementia?

Various neurodegenerative disorders and factors contribute to the development of dementia through a progressive and irreversible loss of neurons and brain functioning. Currently, there is no cure for any type of dementia.

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, treatment, and care strategies.

Other conditions that cause dementia or dementia-like symptoms include:

• Normal pressure hydrocephalus, an abnormal buildup of cerebrospinal fluid in the brain
• Creutzfeldt-Jakob disease, a rare brain disorder
• Huntington’s disease, an inherited, progressive brain disease
• Chronic traumatic encephalopathy, caused by repeated traumatic brain injury
• HIV-associated dementia, a rare disease that occurs when the HIV virus spreads to the brain
• Heavy alcohol use over a long period of time
• Head injury, such as a concussion from a fall or accident
• Emotional problems, such as stress, anxiety, and depression
• Delirium, a sudden state of confusion and disorientation

In addition, medical conditions such as tumors, vitamin deficiencies, medication side effects, or problems with the thyroid, kidney, or liver can also cause serious memory problems that resemble dementia. Some causes of dementia symptoms can be halted or even reversed with treatment. For example, normal pressure hydrocephalus often resolves with treatment.

The similarity in symptoms of various dementias can make it difficult to get an accurate diagnosis. But a proper diagnosis is important to get appropriate treatment.