Why more women get Alzheimer's disease

We know that more women than men get Alzheimer's disease, and an emerging body of research is challenging the common wisdom as to why. Recent studies suggest that biological, genetic, and even cultural influences may play heavy roles. Suffering from depression later life is one of those.

Of the more than 5 million people in the United States who have been diagnosed with Alzheimer’s, the leading cause of dementia, two-thirds are women. Because advancing age is considered the biggest risk factor for the disease, researchers largely have attributed that disparity to women’s longer life spans. The average life expectancy for women is 81 years, compared with 76 for men.

With the number of Alzheimer’s cases in the United States expected to more than triple by 2050, some researchers are urging a greater focus on understanding the underlying reasons women are more prone to the disease and on developing gender-specific treatments.

Running counter to the longevity argument, the research suggests that women who are 70 to 79 years old are twice as likely as men the same age to develop Alzheimer’s or other forms of dementia. After 80, the risk is identical and remains similar throughout the rest of life.

Other variables and theories are at work, such as educational attainment and susceptibility to depression and other ailments that affect women more than men. People with limited education appear to be at higher risk for dementia than those with advanced degrees. Women in the susceptible age group, many born before the modern feminist movement, often were shut out of universities and generally relegated to menial jobs.

Women have a 70 percent risk of developing depression in their lifetime compared with men, and a study published last year in the British Journal of Psychiatry found a link between depression late in life and dementia.

Researchers have focused on sex-specific genetic causes, particularly a specific gene variant, known as APOe4, which is found in about 20 percent of the population. Men and women have about the same chances of carrying the gene, which produces a protein in the liver that transports cholesterol and fatty acids in the body. The risk is 10 times higher for those who have two copies of the gene.

But research suggests that the APOe4 gene confers its Alzheimer’s risk unevenly in women. A recent study led by Michael Greicius, medical director of Stanford Medical School’s Center for Memory Disorders, found that women with the APOe4 gene were twice as likely to get Alzheimer’s as women who did not carry the gene. Yet the risk factor appeared to be little different between men who had the APOe4 gene and those who did not.

“We have now seen again and again that women that have [APOe4] have a much higher risk of getting Alzheimer’s than men of the same age who don’t have the gene,” said Walter A. Rocca, professor of neurology and epidemiology at the Mayo Clinic in Rochester, Minn. He said it’s not fully understood why, but scientists suspect the APOe4 gene appears to interact with estrogen to create the conditions that lead to Alzheimer’s.

A doctor and caretaker herself of her husband Steve, Dr. Mary Newport found in her research that coconut oil helped reversed many of the symptoms linked to Alzheimer's. To read her story and find out how the coconut oil helped, check out her book, Alzheimer's Disease: What is there was a Cure? at www.basichealthpub.com or www.amazon.com.

Next we'll look at how estrogen plays an increased role in getting Alzheimer's.