Risk Factors Associated with Alzheimer’s Disease
The greatest known risk factor for Alzheimer’s is advancing age. As we age, our body’s ability to repair itself becomes less efficient. Most individuals with the disease are age 65 or older. One out of eight people over age 65 has Alzheimer’s. Nearly half of people over age 85 have the disease. The likelihood of developing Alzheimer’s doubles about every five years after age 65. After age 85, the risk reaches nearly 50 percent.
Family history and Genetics
Another strong risk factor in developing Alzheimer’s Disease is family history. Those who have a relative, be it a parent, brother, sister or child with Alzheimer’s are more likely to develop the disease. The risk of Alzheimer’s increases if more than one family member has it.
Twice as many women get Alzheimer’s disease than men. A lot of people believe that it is in a large part a result of the changes to women’s hormones at menopause, particularly the decline of estrogen. However, hormonal changes are not the only factor contributing to the increased incidence of Alzheimer’s disease in women. On average, women live longer than men and age is a risk factor. Women are also more prone to diabetes, which is also a risk factor and recently, a gene was identified that occurs only in women, and appears to somewhat increase the risk for Alzheimer’s disease.
All the risk factors for cardiovascular disease (such as high blood pressure and high cholesterol levels) are also risk factors for both Alzheimer’s disease and Vascular Dementia. The risk of developing Alzheimer’s or vascular dementia appears to be increased by many conditions that damage the heart or blood vessels. These include high blood pressure, heart disease, stroke, diabetes and high cholesterol.
Type 2 diabetes has been known to be a risk factor for Alzheimer’s disease for quite some time. Generally, it has been assumed that the two are linked by cardiovascular disorders, which are associated with diabetes and are risk factors for Alzheimer’s disease. It has also been known that the utilization of glucose in the brains of people with Alzheimer’s disease is impaired, somewhat resembling the situation in the bodies of people with type 2 diabetes. Recently evidence was also presented that children with type 1 (“Juvenile”) diabetes are at risk for developing Alzheimer’s disease in later life.
Scientists don’t know yet exactly how Alzheimer’s and diabetes are connected, but they do know that excess blood sugar or insulin can harm the brain in many ways.
Interestingly, almost all individuals with Down syndrome who live into their forties and beyond will develop Alzheimer’s characteristics. It is important to note, however that not all people with Down syndrome who develop these brain changes will go on to develop dementia.
There is a strong link between serious head injury and the future risk of developing Alzheimer’s disease. Brain injuries are accepted by most doctors as a risk factor for the later development of Alzheimer’s disease.
Other Risk Factors
In addition to the risk factors described above, the following have been shown to be risk factors for developing Alzheimer’s disease: inflammatory conditions (perhaps reflecting immune system malfunction), a history of episodes of clinical depression, stress, and inadequate exercising of the brain.