Alzheimer's and dementia are often used interchangeably by many people. Alzheimer’s and Dementia are similar, but they are not the same.
Dementia is an umbrella term used to describe a set of symptoms that impacts cognitive functioning (such as memory, language, reasoning, problem solving, processing speed, etc.). Dementia is considered a collection of symptoms with no specific cause. As a result, dementia has various different diseases and conditions.
Alzheimer's disease is the most common form of dementia, in which there is a continuous decline in thinking, memory, behavioral, and social skills that disrupts a person's ability to function independently. The early signs of Alzheimer’s may be forgetting recent events or conversations. As the disease progresses, a person with Alzheimer's can develop severe memory impairment and lose the ability to carry out everyday tasks that used to be routine in their daily lives.
But there are several other types of dementia, including:
Vascular dementia: which results from strokes or other conditions that block blood flow to the brain. Vascular dementia (or multi-infarct dementia) is general term describing problems with reasoning, planning, judgment, memory and other thought processes caused by brain damage from impaired blood flow to your brain.
Lewy body dementia (LBD or DLB): which is a result of abnormal protein deposits in the brain which can lead to problems with thinking, movement movements, hallucinations, and mood.
Frontotemporal disorders (FTD): which are types of dementia resulting from damage to the frontal and temporal lobes of the brain that typically impacts behavior/personality and/or language skills.
Mixed Dementia: A form of dementia in which it is possible to have multiple types of dementia at the same time.
More recently, the DSM-5 replaced the terminology of the dementias with a characterization of these neurodegenerative disorders as neurocognitive disorders. Neurocognitive disorders are of concern when there is a clinically significant acquired deficit in cognition that results in a significant decline from a previous level of functioning. They can include delirium, major neurocognitive disorder (such as a dementia), and mild neurocognitive disorder (such as mild cognitive impairment). The underlying etiology varies among individuals, but in the case of major neurocognitive disorder (dementia), several subtypes have been recognized.
The neurocognitive disorders comprise delirium, major neurocognitive disorder, or mild neurocognitive disorder (NCD). The DSM-5 introduced the terms “major neurocognitive disorder” and “mild neurocognitive disorder” as a way to indicate the severity of the impairment. The term “dementia” is avoided in the DSM-5 criteria but may still be used where physicians and patients are accustomed to this term. The term “neurocognitive disorder” is often preferred, especially for conditions affecting younger adults.
Major Neurocognitive Disorder can be distinguished from Mild Neurocognitive Disorder by the severity of the cognitive decline and the impact the symptoms have on the individual’s ability to carry out his or her daily living activities. To meet the diagnostic criteria for an Neurocognitive disorder, individuals must present with significant (major Neurocognitive disorder) or modest (mild Neurocognitive disorder) cognitive decline in one or more domains (including complex attention, executive function, learning and memory, language, perceptual-motor, or social cognition). There should be prior concern that there has been a significant (major) or mild (mild) decline in cognitive function, which is evidenced by substantial (major) or modest (mild) impairment in cognitive performance (preferably evidenced by a standardized cognitive test). The deficits should not occur exclusively in the context of delirium and should not be better explained by another mental disorder. For a diagnosis of mild neurocognitive disorder, the cognitive decline should not interfere with everyday life. For a diagnosis of major neurocognitive disorder, the symptoms must interfere with independence in everyday activities. The clinician must specify the severity of the symptoms for major neurocognitive disorder and whether there are any behavioral disturbances with both mild and major neurocognitive disorder. In addition to cognitive decline, psychosis, mood disturbances, agitation, apathy, and other behavioral symptoms are frequently observed.
A number of conditions, including treatable conditions, can result in memory loss or other dementia symptoms. If you are concerned about your memory or other thinking skills, talk to your doctor for a thorough assessment and diagnosis. The essential feature of a neurocognitive disorder is the development of multiple cognitive deficits that are noticeable enough to cause impairment in daily functioning and represent a decline from a previous level of functioning. If you are concerned about thinking skills you observe in a family member or friend, talk about your concerns and ask about going together to a doctor's appointment.