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Understanding Terms "Dementia" - "Alzheimer's" -

Brain  Diagram

There is often confusion and misunderstanding with the use of the terms “Alzheimer's” and “Dementia”, but there is a distinct difference.

The term “Dementia” is not a disease but rather it describes a set of symptoms while the term “Alzheimer’s” is a disease that causes dementia Symptoms.

The terms are discussed and further defined below by the Mayo Clinic:

Dementia isn't a specific diseaseThe term dementia refers to a set of symptoms, not the disease itself. These symptoms might include language difficulty, loss of recent memory or poor judgment. Symptoms affecting intellectual and social abilities severely enough to interfere with daily functioning. In other words, when an individual is said to have dementia they are exhibiting certain symptoms. Many causes of dementia symptoms exist. Alzheimer's disease is the most common cause of a progressive dementia. With a thorough screening including blood tests (to rule out other causes of dementia such as vitamin deficiency), a mental status evaluation, neuropsychological testing, and sometimes a brain scan, doctors can accurately diagnose the cause of the dementia symptoms such as Alzheimer’s in 90 percent of the cases.”

(1) Memory loss generally occurs in dementia, but memory loss alone doesn't mean you have dementia. (2) Dementia indicates problems with at least two brain functions, such as (a.) memory loss and (b.) impaired judgment or (c.) language. Dementia can make you (d.) confused and unable to remember people and names. You also may experience changes in (e.) personality and (f.) social behavior. However, some causes of dementia are treatable and even reversible.” (Alzheimer’s however is not reversible.)

     Note: Although Alzheimer's disease accounts for 70-80 percent of all cases of dementia symptoms, Mayo Clinic lists 16 other diseases and  disorders that cause dementia symptoms:

(1.)  Lewy Body Dementia

(2.)  Vascular Dementia

(3.)  Front Temporal Dementia

(4.)  Huntington's Disease

(5.)  Dementia Pugilistica - Chronic Traumatic Encephalopathy

(6.)  HIV - associated Dementia

(7.)  Creutzfeldt-Jakob Disease

(8.)  Parkinson's disease 

(9.)  Infections and Immune Disorder Dementias

(10.)  Metabolic and Endocrine abnormalities Dementias

(11.)  Nutritional deficiencies Dementias

(12.)  Reaction to Medication Dementia

(13.)  Subdural Hematomas Dementia

(14.)  Posioning Dementia

(15.)  Brain Tumor Dementia

(16.)  Anoxi (Hypoxia) Dementia.

Mayo Clinic advises that the dementia symptoms such as those caused by a reaction to medications or an infection, are reversible with treatment.


Early stage Alzheimer's would normally not involve dementia symptoms!  -  (Mild memory and thinking functions that do not affect ability to carry on normal daily activities.)


Dementia symptoms vary depending on the cause, but common signs and symptoms include:

1.  Memory loss

2.  Difficulty communicating – language

3.  Inability to learn or remember new information

4.  Difficulty with planning and organizing

5.  Difficulty with coordination and motor functions

6.  Personality changes

7.  Inability to reason

8.  Inappropriate behavior

9.  Paranoia

10.  Agitation

11.  Hallucinations

(Other physical manifestations of Alzheimer’s include incontinence, difficulty swallowing, and inability to walk, or use arms. Inability to talk, seizures --)


New Criteria and Guidelines for Alzheimer’s disease Diagnosis – April 2011. As established by workgroups of the National Institute on Aging (NIA) of the National Institutes of Health and the Alzheimer’s Association.

The new guidelines with the three stages of Alzheimer’s are intended to replace the Alzheimer's Association's old and present classification of 7 stages of Alzheimer’s. The previous 7 stages of classification were to my mind ridiculous and unnecessarily complicated. The medical profession ignored the previous 7 stages of AA and used their own classification system of Early (Mild), Middle (Moderate), and Late (Severe) Stages. The Medical profession's three stage system is still to my mind the most practical and efficiently used method as well as the most easily understood by both the medical profession and the general public. Going from 7 stages to the new 3 stages is however, a huge improvement!

The new Criteria and Guidelines are briefly discussed and outlined:


Three Stages of Alzheimer’s Disease

1st - Preclinical Alzheimer’s Disease

Measureable changes in biomarkers that indicate the earliest signs of disease, before symptoms such as memory loss and confusion about time or place are noticeable. This reflects current thinking that Alzheimer’s begins creating measurable changes in the brain years, perhaps decades, before symptoms occur. While the criteria and guidelines identify this as a stage of Alzheimer’s disease, they do not establish diagnostic criteria that doctors can use now. Rather, they propose additional biomarker research to tell doctors what biomarker results confirm that a person is in this – or another – stage of the disease.

    Note: The recommendations in the article on preclinical Alzheimer’s disease are intended for research purposes only. They have no clinical utility at this time. Much additional research needs to be done to validate the use of biomarkers as they are proposed in the new criteria and guidelines. These studies are likely to take a decade or more to fully accomplish

2nd - MCI  due to Alzheimer’s Disease  (Mild Cognitive Impairment)

Mild changes in memory and thinking abilities that are noticeable to the person and to family members and friends and that can be measured, but that do not affect one’s ability to carry out everyday activities. Many, but not all, people with MCI go on to develop dementia due to Alzheimer’s disease. The guidelines define four levels of certainty for ruling out other causes of MCI and arriving at a diagnosis of MCI due to Alzheimer’s.

3rd - Dementia due to Alzheimer’s Disease

Memory, thinking and behavioral symptoms that impair a person’s ability to function in daily life.

Note: In the year 2011, it is estimated that there were 5.4 million cases of Alzheimer's in the United States. (MCI due to Alzheimer's and Dementia due to Alzheimer's) The stage 1, which is preclinical Alzheimer's is not included in this total.


 Definition of Biomarker as used in stage 1.: A biomarker is something in the body that can be measured and reliably indicates the presence or absence of disease, or the risk of later developing a disease. Two biomarker categories are identified in the criteria and guidelines: (1) biomarkers showing the level of beta-amyloid accumulation in the brain and (2) biomarkers showing the nerve cells in the brain are injured or actually degenerating. The use of biomarkers for all three stages of the disease is proposed, but is intended only for research at this time.