Is Alzheimer’s Hereditary?
Alzheimer's disease is one of several forms of dementia. Dementia is a general syndrome which includes Alzheimer's and other similar conditions. Vascular dementia, dementia with Lewy bodies (DLB), mixed dementia and Parkinson's disease are other conditions which can cause symptoms sometimes similar to Alzheimer's.
Any disease or affliction which damages the brain can result in dementia symptoms. Memory loss, cognitive problems, issues with communication and speech -- all are signs that can suggest dementia.
There are tens of millions of people around the world suffering from some form of dementia. The majority of them, 60% to 70%, have Alzheimer's disease. Alzheimer's and other types of dementia most commonly affect those over 50 or 60 years of age. If your parents or grandparents have Alzheimer's, you might wonder about your own chances of developing the condition. Is it hereditary?
Dementia Is Rarely Inherited
One person diagnosed with dementia might wonder about the chance of passing the condition along to their children. The good news is that, in most cases, dementia is not inherited. However, this depends on the type of dementia that is involved. One exception is Huntington's disease, which can be inherited and can cause dementia.
Studies indicate that 99% of Alzheimer's cases have nothing to do with a person's heredity. It is true that if your parents and/or grandparents developed Alzheimer's your risk is slightly increased. However, this has more to do with the fact that the longer you live, the higher your risk of developing Alzheimer's.
If the people that passed on your family genes consistently lived past the age of 80, the odds are that you will also. That's probably because they passed on healthy living practices that will give you have a good chance of living longer than average. The 80 year hallmark is where incidence rates of Alzheimer's rise dramatically.
When Is Dementia Inherited?
There is a very small number of people with a greater risk of developing Alzheimer's linked to hereditary factors. Less than 1% of all undiagnosed Alzheimer's patients have one of three genes which have been linked to early onset Alzheimer's. When the APP, PS1 and PS2 genes are present, Alzheimer's can start causing problems when the person is in their 30s or 40s. This is often inherited.
In the case where those specific genes are identified, Alzheimer's can be passed on, and was often present in previous generations. This is extremely rare. Other than Huntington's disease, the rare Alzheimer's exceptions, and a small number of Lewy body dementia cases, dementia is not an inherited problem.