Late-onset Alzheimer's Disease - Sporadic Alzheimer's
Late-onset Alzheimer’s disease is the most common form of the illness affecting about 90% of sufferers. It only occurs in people over the age of 65 – hence the name. And alarmingly it appears to affect around 50% of all people over the age of 85.
Late-onset Alzheimer's is also known as “sporadic Alzheimer’s” because there appears to be no genetic factor or family link involved.
What scientists do know, however, is that the likelihood of developing the illness doubles every five years once a person has reached 65. It could be that if we all lived to 150, every single one of us might at some point develop sporadic Alzheimer’s because it may be something that affects everyone eventually - only some get it quicker than others.
Early and late onset Alzheimer’s differs because of the link to family history. However the symptoms and the progression of the disease appear to be exactly the same even though the trigger is believed to be different.
Symptoms Of Late-Onset AD
Late onset Alzheimer’s causes memory loss, confusion and difficulties in carrying out even the simplest tasks. Eventually a person will need constant care as they will be unable to look after themselves.
On average people live roughly eight to ten years after diagnosis. Sometimes with sporadic Alzheimer’s, because it affects people so late in life, another disease associated with old age could also be the cause of death.
There is no cure and the jury is still out as to why some people get it and others don’t. It is indiscriminate of race, colour, creed and lifestyle. In fact the only thing sufferers have in common appears to be old age.
Unfortunately finding genes for incredibly complex conditions like sporadic Alzheimer’s is a complicated business as there appears to be no link between who gets it and who doesn’t.
So far researchers haven’t come across one single gene to determine the eventual development of sporadic Alzheimer’s. What they have done however is identify a gene which may be a risk factor. Apolipoprotein E (ApoE) is found on chromosone 19. What makes that gene so interesting is that it has both a negative and positive side in the development of Alzheimer’s. The e4 type of the gene is found to carry a higher risk of Alzheimer’s while the e2 type is believed to offer protection against it.
It’s important to remember that having this gene doesn’t mean that you will either get or not get Alzheimer’s. Environmental factors, lifestyle and toxins can all play a part in weakening genes and making a person more susceptible to an illness.
Sporadic Alzheimer’s is a very difficult and complex disease for researchers because there is no real rhyme or reason to it. Until they can come up with an identifying factor other than age, there will be no cure.