(LifeWire) - Given that Alzheimer's disease is on the rise worldwide, it's important to know whether certain Alzheimer's risk factors increase or decrease one's chances for developing the disease. In 2006, according to the CDC, Alzheimer's passed diabetes to become the sixth-leading cause of death in the United States.
More than 5 million people in the United States are now living with the disease, and experts predict that number could climb as high as 16 million by 2050. By 2010, the number of new cases could reach half a million per year.
But who gets Alzheimer's disease, and why? Research has revealed important Alzheimer's risk factors that affect one's chances of developing the disease.
The Role of Age and Gender
The greatest risk factor for Alzheimer's Disease is age. About 13% of people older than 65 have dementia. There are observed differences in gender -- 16% of women 71 years or older have dementia, while that rate is 11% in men of the same age group. Many researchers are quick to note that this difference may have more to do with women's greater longevity than with any gender-based propensity to dementia.
Lifestyle and Race/Ethnicity
A growing body of Alzheimer's research links the disease to lifestyle-related factors, such as obesity, high blood pressure, high cholesterol and diabetes, which are all associated with a modern Western lifestyle.
In addition, certain racial/ethnic groups in the United States are more prone to the disease than their counterparts abroad. Japanese-American men, for example, have significantly higher rates of Alzheimer's disease than men of comparable age in Japan. Other studies have found higher rates of the disease among African-Americans than among Africans.
There are also studies that address differences between racial/ethnic groups within the United States. The Alzheimer's Association estimates that the rates of dementia may be higher among African-Americans than among whites. African-Americans also have significantly higher rates of high blood pressure and type 2 diabetes.
Emotional Health, Mental Activity and Alzheimer's
People with a history of depression also appear to be more vulnerable to Alzheimer's disease. A study from the Netherlands found that the earlier a person experienced symptoms of depression, the more likely they were to develop Alzheimer's later in life.
On the other hand, Alzheimer's is less common among the highly educated. This doesn't appear to be the result of a more health-conscious lifestyle. Rather, some researchers believe it is a beneficial consequence of lots of learning and use of memory among people who have more education.
Experts stress that Alzheimer's risk factors such as age, gender, race/ethnicity, lifestyle, psychological well-being, and education will not necessarily cause or prevent Alzheimer's disease. Understanding their role, however, is an important step in facing the challenges of this disease.Suggested Reading:
- What Causes Alzheimer's Disease?
- Can Alzheimer's Be Prevented?
- Exercise and Brain Fitness
- Depression and Alzheimer's Disease: A Complex Relationship
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