What is Dementia?
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Dementia is an umbrella term for various diseases that affect an individual's cognitive functioning, such as thinking, remembering, decision-making, and behavior, which affects a person's daily life, relationships with others, and ability to do everyday activities. The most common types of dementia are Alzheimer's disease, which accounts for 60-70% of dementia cases, Vascular dementia, Lewy Body dementia, Frontotemporal dementia, and Mixed dementia, where symptoms of multiple types of dementia are present in a person's brain at the same time. In 2023, more than 55 million people have dementia worldwide, and there are an estimated 10 million new cases of dementia every year. Contrary to what people may believe, dementia is not a normal part of aging, as many older adults live their lives without developing dementia.
Symptoms of Dementia
Memory loss is one of the most recognizable symptoms of dementia, and it is what people usually associate dementia with. However, there are a variety of other symptoms that people may experience depending on what kind of dementia they have, but all forms of dementia share a set of symptoms that may include:
  • Memory loss, including forgetting things, confusion, and losing or misplacing things
  • Poor judgment, acting impulsively, difficulty completing tasks
  • Difficulty expressing thoughts, speaking, following conversations, and reading and writing
  • Changes in behavior or mood, like personality changes or losing interest in activities
  • Trouble with vision perception, balance, and movement
  • Losing track of time
Factors that increase the risk of Dementia
  • Age
    This is the most substantial risk factor for dementia, with most cases affecting people 65 years and older.
  • Family History
    People with family members with dementia are more likely to develop dementia themselves.
  • Poor Health
    People with poor health or conditions like high blood pressure, diabetes, being overweight or obese, high cholesterol, or a history of drinking or smoking are more likely to develop dementia.
  • Head Injuries
    Head injuries can increase the risk of someone developing dementia, especially if the injuries are severe or occur repeatedly.
  • Social isolation and depression
    Researchers are just only starting to understand the effect of social isolation and depression and how it increases the chances of people developing dementia. Some studies have linked social isolation and depression to people drinking heavily, smoking, not exercising, being overweight, and having heart problems, which are all understood factors that increase the chances of developing dementia, but no clear relation is yet to be seen between social isolation and depression and the increased chances of people developing dementia.
Most common types of Dementia
  • Alzheimer's Disease
    Alzheimer's Disease is the most common type of dementia, accounting for roughly 60-70% of dementia cases worldwide. It is a progressive disease that negatively impacts memory, cognitive abilities like conversation and problem-solving, and a person's ability to carry out simple tasks. It also shares many symptoms with other types of dementia, like memory loss, poor judgment, a person's ability to hold conversations, and behavior. It has many stages and starts with an individual becoming asymptomatic, where no symptoms are present, but changes are happening in the brain that will eventually lead to Alzheimer's Disease. Eventually, Asymptomatic will lead to Mild Cognitive Impairment, Mild dementia, Moderate dementia, Severe dementia, and death.
  • Vascular Dementia
    Vascular dementia is a type of dementia that is linked to strokes and inadequate blood flow to the brain and accounts for 10% of all dementia cases worldwide. This type of dementia can either occur suddenly after a major stroke or can occur gradually and worsen as a result of a minor stroke. Researchers have also seen a strong link between cardiovascular disease and cerebrovascular disease with dementia and other cognitive impairments. Vascular dementia and other vascular brain changes often coexist with changes and symptoms that are linked to other types of dementia, including Alzheimer's and Lewy Body dementia.
  • Lewy Body Dementia
    Lewy Body dementia is another common type of progressive dementia and occurs when abnormal deposits of a protein called alpha-synuclein occur in the brain. These deposits, called Lewy bodies, cause chemical changes in the brain, which leads to problems with thinking, movement, behavior, mood, and other common symptoms of dementia. This type of dementia is particularly challenging to diagnose, as early symptoms of Lewy Body dementia are often confused with other dementias and psychiatric disorders. Lewy Body dementia can also occur with different kinds of dementia and brain disorders.
  • Frontotemporal Dementia
    Frontotemporal dementia is a kind of dementia that occurs as a result of progressive nerve cell loss in the brain's frontal lobes or temporal lobes. There are also two kinds of frontotemporal dementia: frontal variant, which affects behavior and personality, and primary progressive aphasia, which again has two subtypes: progressive nonfluent aphasia, which affects a person's ability to speak, and semantic dementia, which affects the ability to use and understand language. Frontotemporal dementia as a whole is less common in those over the age of 65, but it is more common in younger adults aged 45 to 65, as is as common as younger-onset Alzheimer's.
  • Mixed Dementia
    Mixed dementia is where brain changes of more than one type of dementia are present in a person's brain. In the most common scenario of mixed dementia, it is usually Alzheimer's disease coexisting with problems linked to vascular dementia, issues linked to Lewy Body dementia, or in some cases, these three types of dementia are present in a person's brain at the same time. It is tough to diagnose someone with mixed dementia because they are usually diagnosed with one specific type of dementia, and it is not known that they had more than one kind of dementia until death.
Diagnosis
A dementia diagnosis is a very lengthy process of tests, evaluations, scans, and physical exams to find what type of dementia a person might have and what kind of treatment plan that person would have to undergo to lessen the effects of dementia. The first step many doctors take is identifying any underlying condition related to cognitive difficulties. Once any symptoms and conditions are out ruled, the person undergoes cognitive and neurological testing, which evaluates memory, problem-solving, language skills, math skills, balance, sensory responses, and reflexes. Brain scans like CT scans, MRI scans, and PET scans are also used to identify any possible strokes, tumors, and other brain problems in a person's brain that might cause dementia. If a person is experiencing behavioral problems or mood changes, they might undergo a psychological evaluation, in addition to all the other tests, to determine if any underlying mental health conditions are causing or contributing to a person's symptoms. Some forms of dementia are also linked to genetic variations in a person's genes, so in these rare cases, if determined necessary, a person might undergo genetic testing to determine if they have any altered genes that can cause a person to develop dementia. Some forms of dementia cause a buildup of various proteins in a person's brain, so cerebrospinal fluid tests are also sometimes conducted to measure the levels of proteins and other substances in a person's cerebrospinal fluid, which are used to diagnose Alzheimer's and some other types of dementia if present.
Early detection of symptoms and the type of dementia are essential, as some causes of dementia can be treated. Also, obtaining an early diagnosis can help families plan for the future, such as how to manage the condition and what to do in the future if their condition worsens. The first step to obtaining a diagnosis if you or a family member are experiencing changes in thinking, memory, mood, or behavior is to contact your primary care doctor, who can refer you to a neurologist, someone who specializes in disorders of the brain and nervous system. Geriatric psychiatrists, neuropsychologists, and geriatricians are specialists who can also assist in the diagnosis of dementia for yourself or your loved one.