Late-onset Alzheimer’s Disease
This is the most common form of Alzheimer’s disease, accounting for about 90% of cases and usually occurring after age 65. Late-onset Alzheimer’s disease strikes almost half of all people over the age of 85 and may or may not be hereditary. Late-onset dementia is also called sporadic Alzheimer’s disease.
Although they have not yet identified the actual gene, researchers have evidence that a gene located on human chromosome 10 could be more potent than previous risk factors for late onset Alzheimer’s disease.
The report follows closely on another study reporting that statins, widely prescribed cholesterol-lowering drugs, could prevent certain neural changes that signal the progression of Alzheimer’s disease. Additional earlier studies support the idea that statins could benefit Alzheimer’s patients; however, other studies have found no such protective effect from statins.
Genetic factors for late onset Alzheimer’s disease
1. ApoE4 is associated with a higher risk of Alzheimer’s. About a quarter of the population inherits one copy of the ApoE4 gene, which increases their risk of developing Alzheimer’s disease by up to four times.
2. Two per cent of the population get a ‘double dose’ of the ApoE4 gene, one from each parent. Their risk of developing Alzheimer’s disease is increased by about ten times.
Do genes cause late-onset Alzheimer’s?
In this version of the disease, which strikes after age 65, genes are thought to influence the risk but do not directly lead to disease, says Marilyn Albert, spokeswoman for the Chicago-based Alzheimer’s Association. Late-onset Alzheimer’s is different from the early onset of the disease: In a tiny fraction of families, a gene mutation does directly lead to Alzheimer’s, she says. People who inherit the bad gene almost always develop the disease, usually in their 40s.
Symptoms Of Late-Onset Alzheimer’s Disease
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.
Facts about Alzheimer’s Disease
Alzheimer’s disease, which affects 4.5 million Americans, is differentiated as either early-onset or late-onset. The early-onset form is rare and tends to affect those between the ages of 30-60. Most cases of early-onset are genetic, caused by a mutation of the APP gene. The late-onset form is much more common – accounts for 90 percent of all cases of Alzheimer’s – and tends to affect those aged 65 and older.
