For Alzheimer's disease (AD), age is by far the greatest risk factor. Most individuals with the disease are 65 or older, and the likelihood of developing AD doubles about every 5 years after age 65. After age 85, the risk reaches nearly 50 %. Another important risk factor for AD is family history. Research has shown higher risk among those with the first-degree relatives with AD. The risk increases if more than one family member has AD.

Despite the fact that certain risk factors such as age, genetic dispositions, and family history cannot be changed, there are many risk factors that you can identify and manage by choosing a healthy life style and by using appropriate risk-reducing treatments.

These risk factors include but are not limited to:

• Stroke increases an individual's risk of developing vascular dementia by 6-10 times. So maintaining good cardiovascular health and proper blood flow to the brain is important.
• Diabetes increases the risk for stroke, heart disease and hypertension, all conditions that increase the risk of vascular dementia. Additionally, diabetes also impairs cognitive function in those with AD.
• Heart diseases including heart valve diseases, coronary artery disease and atrial fibrillation reduce blood flow to the brain. Poorly controlled heart diseases lead to large or small strokes anywhere in the brain.
• High cholesterol increases the production of beta amyloid, one of the hallmarks of AD, and doubles the risk of the disease.
• High blood pressure is a major risk for vascular dementia.
• Head injury especially with loss of consciousness in individuals with a genetic disposition to AD increases the risk of the disease ten fold. Also, head injury with or without loss of consciousness increases the risk for seizure, which can begin up to several years after the injury. Seizure is a risk factor for cognitive impairment or dementia if it is not controlled well.

Additional risks include:

• Severe estrogen deficiency
• Severe testosterone deficiency
• Certain cancer treatments
• Alcohol or chemical abuse
• Regular tobacco use now or in the past
• Unhealthy diet
• Lack of mental and physical exercise