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Dementia affects more than 55 million people around the world. It is an important cause of death and disability among older adults, and its global cost reaches 1.3 trillion U.S. dollars annually.

What is dementia?

People with dementia experience loss of memory and problems with reasoning and other mental abilities that interfere with their daily activities. Some patients with dementia may also encounter personality changes or difficulties with controlling their emotions. Notably, the term “dementia” encompasses several different diseases and not just a single disorder. Although the risk of dementia increases with age, it is not a normal part of aging.

Types of dementia

Several of the diseases causing dementia that have a particularly high impact on patients, caregivers, and society include:

  • Alzheimer’s disease,which is the most common type of dementia in older adults, accounts for approximately 60%–70% of dementia cases. In the brains of patients with Alzheimer’s disease, there is a loss of neuronal cells (neurodegeneration) and abnormal accumulation of amyloid-beta and tau proteins, forming amyloid plaques and tau tangles.
  • Vascular dementia develops when blood flow in the brain is impaired, or blood vessels are damaged. This compromises blood flow to the brain and reduces the brain’s access to oxygen.
  • Frontotemporal dementia is a rare dementia type, in which tau and TDP-43 proteins accumulate in the brain, and the frontal lobe degenerates.
  • In Lewy body dementia, a protein called alpha-synuclein accumulates inside neuronal cells in the brain and forms Lewy bodies.
  • Mixed dementia – Some patients may experience brain changes that are typical of two or more dementia types.
  • Other causes - nutritional deficiencies, heavy alcohol consumption and head injury.

What causes dementia?

Clinical signs of dementia develop due to changes in neuronal cells in the brain, but the underlying causes and mechanisms may vary.

In dementia induced by neurodegeneration, there is impaired function of neuronal cells, loss of connections among them, and progressive neuronal cell death. This, in turn, leads to brain function impairments that are severe enough to interfere with activities of daily living.

However, clinical signs of dementia may also develop due to potentially reversible causes, such as nutritional deficiencies or depression. Other conditions, such as heavy alcohol consumption or a head injury, can also cause dementia.

Clinical signs of dementia

The symptoms of dementia may vary among patients and dementia types. Some of the most common symptoms include:

  • Memory loss
  • Confusion
  • Difficulties expressing or understanding ideas
  • Needing a longer time to complete daily activities
  • Losing interest in previously enjoyed events or activities
  • Getting lost in a familiar environment

In addition, patients with dementia may experience hallucinations or changes in their mood or behavior.

How is dementia diagnosed?

The diagnosis of dementia is complex and requires a combination of examinations and diagnostic tests. Moreover, physicians search for both neurodegeneration and potentially reversible causes of dementia symptoms, such as nutritional deficiencies or depression.

The most commonly used diagnostic procedures include:

  • Collecting patients’ medical history and physically examining them
  • Assessing patients’ cognition (memory and thinking) with specific tests
  • Collecting images of the brain with brain scans
  • Evaluating the cerebrospinal fluid (fluid surrounding the spinal cord) for biomarkers (disease markers)
  • Assessing patients’ mental state
  • Using genetic tests to search for predisposing genetic factors
  • Utilizing blood tests to look for potential biomarkers

Can blood testing serve as a screening tool for dementia?

Blood samples are an attractive candidate tool for dementia screening, as they are more easily accessible than cerebrospinal fluid samples, and their analysis is more affordable than advanced brain imaging. One blood test that can serve as a screening tool is Labcorp’s Amyloid-Tau-Neurodegeneration (ATN) Profile test. It assesses the presence of three potential biomarkers for Alzheimer’s disease (markers for amyloid plaques, tau tangles, and neurodegeneration) in a blood sample. The findings of this test can help identify patients who need advanced testing for Alzheimer’s disease.

Dementia treatment

The treatment of dementia may vary depending on the underlying cause. No cure has been found yet for dementia caused by neurodegeneration, like Alzheimer’s disease. However, some medications can help slow down cognitive decline and manage changes in behavior. Moreover, educating patients with dementia on the significance of self-care and advanced planning can help improve their well-being.