Although there are no definitive causes for Alzheimer's, there are two key risk factors for this disease that have been identified by researchers:
- Age: Senior citizens are at a higher risk for this disease, especially once they reach the age of 65. In fact, about five percent of Americans aged 65 to 74 have Alzheimer's disease. Estimates also claim that almost half of Americans 85 years or older have the disease.
- Genetics: Some cases of Alzheimer's appear to run in the family. Scientists have found a gene called Apolipoprotein E (ApoE) that appears to be a risk factor for the disease. The gene comes in three forms: ApoE2, ApoE3 and ApoE4. Interestingly, the gene ApoE4 may increase the risk for Alzheimer's, while ApoE2 may help to prevent it. In general, having a close blood relative with the disease indicates an increased risk of developing Alzheimer's.
There are a few other risk factors that may be linked to Alzheimer's. Although these indicators are still being researched, scientists have reason to believe that these factors may increase an individual's risk of developing Alzheimer's:
- Cardiovascular disease: The presence of cardiovascular diseases may increase the risk of developing the disease. Many factors that increase the risk of heart disease, such as high cholesterol, smoking and lack of exercise, may also increase the risk of Alzheimer's.
- Type 2 diabetes: Type 2 diabetes involves the body converting blood sugar into energy inefficiently, which leads to higher levels of insulin and blood sugar. This may harm the brain and contribute to the development of Alzheimer's.
- Oxidative damage: Free radicals often attack other molecules to attain stability, harming cells and tissues in the process. This could lead to brain cell damage linked to Alzheimer's disease.
- History of head traumas: Those who have experienced multiple head injuries tend to have a higher risk for this disease.
- Female gender: Women may be at a higher risk for Alzheimer's, due in part to the fact that they tend to live longer than men.