The Basics of Alzheimer’s & Related Dementias

People often use the terms 'Alzheimer's disease' and 'dementia' interchangeably, but they actually mean different things. We find it useful to think about the different stages of progression, including the presymptomatic stage, mild cognitive impairment (MCI), and dementia. In the presymptomatic stage, a person has no impairments but would show an abnormal build up of amyloid plaques (“Alzheimer's pathology”) on a brain scan. Mild cognitive impairment is the term for early cognitive symptoms, when a person still may work, drive, and enjoy hobbies but notices that these activities are taking a bit longer. Dementia is a general term used to describe losses in memory and other intellectual abilities that interfere with daily life and worsen over time.

These areas may be affected:

•Remembering recent events

•Planning, problem-solving, and decision-making

•Knowing the date or the time

•Finding their way in familiar places

•Doing tasks such as cooking, driving, and paying bills

•Communicating with others

People with dementia live an average of eight years after their symptoms become noticeable to others, but survival with the disease can range from three to 20 years, depending on age, other health conditions, and the cause of the dementia (Symptoms are not always due to Alzheimer's disease pathology. See causes of dementia below). In the late stage of dementia, a person typically relies on others for all of his or her daily needs.

♦ Sources: Living with Memory Loss: A Basic Guide by the UW Memory and Brain Wellness Center; the National Institute on Aging. 

Causes of Dementia

Many things can cause changes in memory and thinking. Some of these are depression, a lack of some vitamins and minerals, and head injuries. But if these causes are ruled out or treated, and symptoms keep getting worse, the cause is likely a disease that slowly causes damage to brain cells, or a neurodegenerative disease. There are 4 common types of neurodegenerative disease:

 

1. Alzheimer's disease (AD) is the most common cause of dementia, accounting for most (50 to 70 percent) cases of dementia. It results from the buildup of protein deposits (amyloid plaques and tau) in the brain over many years. The part of the brain that helps you form new memories is affected first. The greatest known risk factor for Alzheimer’s disease is increasing age. People 65 years and older have a 10% risk of developing symptoms of Alzheimer's disease, and the risk rises from there. See Genetics.

More Information:

 

2. Lewy body dementia (LBD) occurs when protein deposits called Lewy bodies build up in areas of the brain. Symptoms include changes in movement, memory, and thinking. There are 2 types:

–Dementia with Lewy bodies

–Parkinson's disease dementia

 

3. Vascular dementia occurs when small blood vessels in the brain are damaged or when a stroke affects the brain.

 

4. Frontotemporal disorders comprise several different progressive neurological disorders that affect cognition, behavior, and/or language, and lead to dementia. These include behavioral variant frontotemporal dementia (FTD), primary progressive aphasia, and FTD-motor neuron disease or movement disorders. In about 15 to 40 percent of people, a genetic (hereditary) cause can be identified. Individuals with a family history of frontotemporal disorders are more likely to have a genetic form of the disease than those without such a history. Frontotemporal disorders usually onset before age 65. Please see Genetics.

 

• Mixed dementia occurs when more than one problem causes changes in memory and thinking. For example, someone could have protein buildup linked with Alzheimer disease and blood vessel problems that lead to vascular dementia. Or, someone could have the protein buildup of Alzheimer's disease and also have Lewy bodies.

* Other causes of dementia include Huntington’s disease, Creutzfeldt-Jakob disease, severe alcoholism, and HIV. In addition, some conditions that cause dementia, such as normal pressure hydrocephalus, thyroid problems, and vitamin B deficiency, can be reversed with appropriate treatment. 

 

Treatment & Resources

Treatments are available for the symptoms Alzheimer’s disease and related disorders. Although current treatments cannot stop neurodegenerative diseases from progressing, they can temporarily slow the worsening of symptoms and improve the quality of life for people with the disease and their caregivers. The first class of drugs aids a chemical in the brain called acetylcholine: donepezil (Aricept), rivastigmine (Exelon) and galantamine (Razadyne). Memantine (Namenda) works on a different messenger, called glutamate. UW researchers have shown that the drug Prazosin can help resolve behaviors such as agitation, nighttime wandering, uncooperativeness, and aggression in patients with dementia, while causing fewer side effects than antipsychotics.

To prolong independence and possibly delay symptoms, clinicians at the UW Memory and Brain Wellness Center (MBWC) recommend getting regular exercise, staying connected with family and friends, keeping the mind active, eating a healthy diet, reducing stress, and trying to sleep well.

The UW Memory and Brain Wellness Center (MBWC) Education and Community Impact Program aims to improve the wellbeing of people living with memory loss and their families and help them stay active and engaged in their communities:

Community Events & Programs

► The MBWC team offers a handbook for people diagnosed with Alzheimer's and related conditions, Living with Memory Loss: A Basic Guide. Read online or download.

Local & Online Resources

 

Next Up: Evidence-Based Prevention