The type of dementia known as Alzheimer's disease was first described in 1907 by Alois Alzheimer. This physician published a description of a 52 year old woman who began to exhibit extreme jealousy of her husband to the point of paranoia and then later developed memory loss and eventually agnosia (poor ability to recognize typical objects), apraxia (difficulty with activities such as walking, despite good strength), and aphasia (loss of the ability to produce and/or understand language).
Upon the death of this woman Dr. Alzheimer examined her brain and noted changes that we now call "senile plaques" when compared with the brains of similarly aged individuals dying from other causes. Soon after Alzheimer's description, this disorder became known as Alzheimer's disease as more and more cases were reported. For the past century, further study of memory loss and dementia in older individuals has shown that Alzheimer's dementia or Alzheimer's disease accounts for most of dementia in older people.
Alzheimer's disease increases rapidly after the age of 60 and the prevalence of Alzheimer's doubles every 5 years until at least the age of 85 and probably beyond. Because life expectancy is expanding in the developed world, it is likely that physicians and families will face more and more cases of Alzheimer's dementia in the coming 25 to 50 years. It is expected that the number of persons with Alzheimer's dementia may triple within the next four decades.
What we now know about Alzheimer's is that it is a condition that begins even before memory loss appears. Families of people with Alzheimer's often note changes in personality and needs well before the diagnosis of Alzheimer's is made in a physician's office. A major goal of the Kulynych Center is to develop methods for early identification of persons who might develop dementia of the Alzheimer's type, so that strategies for preventing memory loss and treating the changes in the brain consistently with Alzheimer's dementia may be developed and implemented.
Unusual Forms of Alzheimer's Disease
Most patients with Alzheimer's disease show initial problems with memory. However, about 15-20% of patients with Alzheimer's disease will have changes in personality, language ability, or difficulty processing spatial images and interpreting them as their first symptoms. Over time, most of these patients begin to resemble patients with typical Alzheimer's disease. However, Alzheimer's disease is complex and our understanding of the factors that contribute to Alzheimer's disease is consistently growing. It is likely that in the future some diseases we currently call Alzheimer's disease may indeed not be Alzheimer's. Or perhaps we will develop a better classification system for variations in Alzheimer's disease just as we now have different classifications for different types of heart disease and heart failure.
Is there a genetic or family history component of Alzheimer's disease? Am I more likely to get Alzheimer's disease if my parent has Alzheimer's disease?
Most cases of Alzheimer's disease are not inherited. Alzheimer's disease that has an onset before age 65 is more likely to have a genetic link. Gene mutations have been discovered on the 21st, 14th, and 1st chromosomes which cause familial Alzheimer's disease. However, these mutations account for less than 5% of all cases of Alzheimer's disease in the world.
For those individuals with family members (a brother, sister, father or mother) over the age of 65, the presence of the ApoE e4 indicates a higher risk for developing dementia of the Alzheimer's type. Even so, this still accounts for only about 30% of Alzheimer's dementia. The majority of patients with Alzheimer's disease do not have a family history. Even among identical twins, if one has Alzheimer's, the other will develop it less than 40% of the time.
It is important to remember that ApoE-e4 does not cause Alzheimer's disease. It is only associated with a higher chance of developing Alzheimer's disease. Half of the people with Alzheimer's disease worldwide do not carry the ApoE-e4 gene and only about 30-40% of the people who carry the ApoE-e4 gene are likely to develop Alzheimer's disease.
Can Alzheimer's disease be treated?
At present there is no medication that can halt the progression of memory loss and disability associated with Alzheimer's disease. All dementias, including Alzheimer's disease, are treatable, although the treatment does not reverse the disease.