Commonly known as plaques and tangles, these abnormalities are:
Neurofibrillary Tangles
Tangled structures formed from dendrites and axons hinder communication between neurons and networks.
Beta Amyloid
This sticky substance forms clumps which are called plaques.
Tangles and plaques cause damage to healthy brain cells around them which causes the brain to whither and shrink.
Other Risk Factors for Alzheimer’s Disease
Age
The most implicated factor in assessing risk for developing Alzheimer’s disease. Studies indicate that 10% of persons over the age of 65 will develop the disease, and 50% of persons over 85 have it.
Family History
Researchers estimate a 35% probability that the offspring of those who have Alzheimer’s will also develop the disease themselves.
Gender
Women have a significantly greater chance of developing the disease than do men. Women are estimated to face a 1 to 6 chance of manifesting symptoms whereas men have a 1 to 11 chance of developing the disease.
Down Syndrome
For reasons that are not understood, those with Down Syndrome frequently develop Alzheimer’s between the ages of 30 and 45.
Head Injury
Significant head injuries are linked to increased risk of Alzheimer’s. Injuries that require hospitalization or medical treatment are thought to increase the risk by 50%.
Low Education Level
While not clearly understood, a number of studies indicate that low levels of education are correlated with an increased risk for Alzheimer’s. Some believe that because connections in the brain increase as we learn, that the less someone has learned over a lifetime, the less protection they will have against the onset of the disease.
Environmental Toxins
Many researchers believe that exposure to toxic substances can enhance the risk of Alzheimer’s. While those who live and work in environments with high levels of ambient toxicity also commonly meet many other risk factors, clinicians are concerned about the Alzheimer’s risk posed by such exposure.
High Cholesterol/High Blood Pressure
Common circulatory problems are thought by some researchers to impose a tax on the entire body over time, including stress to the tissues in and around the brain which they believe may cause an increased vulnerability to the effects of Alzheimer’s.
Heart Disease
The brain is the most nutrient intensive organ in the body. When decreased cardiovascular efficiency and hindered circulation are present over time, it is thought that the brain may sometimes be deprived of the nutrients it needs to remain healthy into advanced age.
Stroke
After a stroke has damaged large portions of brain tissue, remaining brain structures are relied upon to compensate for lost functionality. Once this compensation has taken place the brain’s normal plasticity is decreased, leaving the brain more vulnerable to the effects of Alzheimer’s.