What are the other Names for this Condition? (Also known as/Synonyms)

• Late-Onset FAD
• Late-Onset Familial Alzheimer’s Dementia
• Late-Onset Inherited Alzheimer’s Disease

What is Late-Onset Familial Alzheimer Disease? (Definition/Background Information)

• Late-Onset Familial Alzheimer Disease, is a form of familial Alzheimer disease (FAD), that begins after age 65
• In general, Alzheimer disease (AD) is a degenerative disease of the brain that causes gradual loss of memory, judgement and the ability to function socially
• The exact underlying cause of Late-Onset Familial Alzheimer Disease is not completely understood; however, researchers suspect that it is a complex condition, which is likely associated with multiple susceptibility genes in combination with environmental and lifestyle factors
• A gene called APOE has been studied extensively as a risk factor for the disease. In particular, a variant of this gene called the "e4 allele" seems to increase an individual's risk for developing late-onset Alzheimer disease (people who have this allele are said to have the Late-Onset Familial AD type 2)
• It is important to understand that APOE is a susceptibility gene, not a determinative gene, which means that people having two copies of this allele have an increased risk of having AD but not necessarily will have it.
• There is no cure for Alzheimer disease. Treatment is supportive and based on the signs and symptoms present in each person

(Source: Late-Onset Familial Alzheimer Disease; Genetic and Rare Disease Information Center (GARD) of National Center for Advancing Translational Science (NCATS), USA.)

Who gets Late-Onset Familial Alzheimer Disease? (Age and Sex Distribution)

• Late-Onset Familial Alzheimer Disease is a rare congenital disorder. The presentation of symptoms occurs after the age of 65 in older adults
• Both males and females may be affected
• Worldwide, individuals of all racial and ethnic groups may be affected

What are the Risk Factors for Late-Onset Familial Alzheimer Disease? (Predisposing Factors)

• A positive family history may be an important risk factor, since Late-Onset Familial Alzheimer Disease can be inherited in a few cases
• Individuals carrying one or both e4 allele(s) of APOE gene are at an increased risk of developing this condition. Those with two e4 alleles bear a higher risk than individuals with one allele
• Some variants of MS4A4/MS4A6E, CD2AP, CD33, EPHA1, APP, PSEN1, PSEN2 and BDNF genes, among others, may also increase the risk for developing this disease

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Late-Onset Familial Alzheimer Disease? (Etiology)

• The exact cause of Late-Onset Familial Alzheimer Disease is not known. It is believed that genetic, environmental and lifestyle factors contribute to the development of the condition
• Research has shown the APOE to be a susceptibility gene. In particular, the e4 allele of this gene renders an individual susceptible to developing Late-Onset Familial Alzheimer Disease. Carrying both copies of the gene as e4 alleles further increases the risk
• However, it must be noted that carrying the e4 allele(s) does not always lead to the disease. It is just one of the risk factors, and environment and/or lifestyle may play a role in the development of the condition
• A genome-wide association study has revealed that certain common variants of MS4A4/MS4A6E, CD2AP, CD33 and EPHA1 may be associated with this disorder as well
• In addition, variants of several other genes (Examples: APP, PSEN1, PSEN2 and BDNF) have also been reported to be associated with the disease 
• The inheritance pattern of Late-Onset Familial Alzheimer Disease is not clear at the present time

What are the Signs and Symptoms of Late-Onset Familial Alzheimer Disease?

The signs and symptoms of Late-Onset Familial Alzheimer Disease may include the following:

• Memory loss and associated problems
• Difficulty performing daily activities, difficulty reading, sleeping
• Agitation
• Depression
• Anxiety
• Mental retardation

How is Late-Onset Familial Alzheimer Disease Diagnosed?

Late-Onset Familial Alzheimer Disease is diagnosed on the basis of the following information:

• Complete physical examination
• Thorough medical history evaluation
• Assessment of signs and symptoms
• Laboratory tests
• Imaging studies
• Biopsy studies, if necessary

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Late-Onset Familial Alzheimer Disease?

The complications of Late-Onset Familial Alzheimer Disease may include:

• Alzheimer’s disease (AD) is the most common cause factor for dementia. Dementia is a type of disorder accompanied by a collection of symptoms that indicate brain impairment and loss of brain function
• Since AD is a progressive disorder, it can create difficulties in the life of the individual and their family members
• As symptoms worsen, it becomes more and more difficult for those affected by the condition to carry out even simple, everyday tasks. They are usually unable to live on their own
• The symptoms may also worsen to the point of death

Complications may occur with or without treatment, and in some cases, due to treatment also.

How is Late-Onset Familial Alzheimer Disease Treated?

There is no cure for Late-Onset Familial Alzheimer Disease. Medical professionals have developed various treatment options to help treat the symptoms of the disorder. These include:

• Use of medications (to treat behavioral problems, aid in performing daily activities)
• Use of therapy sessions (helps an individual to better remember basic activities, things, etc.)

How can Late-Onset Familial Alzheimer Disease be Prevented?

Since multiple factors, such as genetic, environmental and lifestyle factors, may play a role in the development of Late-Onset Familial Alzheimer Disease, currently there are no methods or guidelines available for its prevention.

• However, the following measures may lower the likelihood of developing the disorder. These include:
  • Mental stimulation/brain exercises
  • Regular exercising
  • Healthy, balanced diet
• Active research is currently being performed to explore the possibilities for treatment and prevention of inherited and acquired genetic disorders

Regular medical screening at periodic intervals with tests and physical examinations are recommended.

What is the Prognosis of Late-Onset Familial Alzheimer Disease? (Outcomes/Resolutions)

• As the length of time with Late-Onset Familial Alzheimer Disease increases, symptoms of the disease progressively worsen. In most cases, individuals lose the ability to function in day-to-day life, making them dependent upon their family members, or else by having to move into a nursing home
• Normally life-long management of the condition is necessary. Early detection and aggressive management of Alzheimer’s dementia, with regular health checkups and supportive care are essential. This will prevent further rapid deterioration of the condition and help sustain the quality of life
• Typically, the prognosis may be assessed on a case-by-case basis

Additional and Relevant Useful Information for Late-Onset Familial Alzheimer Disease:

The following DoveMed website link is a useful resource for additional information:

http://www.dovemed.com/diseases-conditions/rare-disorders/