Women are statistically more likely than men to develop Alzheimer’s disease and other forms of dementia. While 16 percent of women over 71 years old develop the degenerative brain disorder, only 11 percent of men of the same age are afflicted with it. That women live longer on average than men may explain this difference, but changes in hormone levels may also play a factor.

Dr. Samuel Gandy, a researcher at Mount Sinai Hospital, says the protein plaques and tangles that make up Alzheimer’s disease begin to build up for largely unknown reasons in men and women in their 50s, if not earlier. "That is very similar to the time when menopause and andropause, the male equivalent, both occur," he says in Big Think's latest special series, Breakthroughs: Alzheimer's Disease. "That coincidence has sparked a lot of interest to understand if the hormonal changes are sort of the trigger that determine the midlife turn towards Alzheimer’s disease."

Estimated Lifetime Risks for Alzheimer’s by Age and Sex*

Alzheimer's Disease by Gender

Research also indicates that in the U.S. African-Americans are about twice as likely—and Hispanics one and a half times more likely—than older whites to get Alzheimer’s disease and other forms of dementia.  This is becoming a bigger concern than ever, as African-Americans and Hispanics will make up a larger proportion of the U.S. population over the next few decades.

Johns Hopkins Alzheimer's researcher Dr. Juan Troncoso, who studied the disease in African-Americans, says that the difference in prevalence between the races could be due to multiple factors: "People may have a different culture background. They may have different education, so those tests are in many ways suspect." Yet, "African-Americans tend to have more vascular disease, so that may be a contributing factor to dementia." Vascular disease factors (including high blood pressure and diabetes) increase the risk for Alzheimer's, so the difference in rates of the disease between racial and ethnic groups could stem from non-genetic factors (which might potentially be reduced through changing diet, education, exercise and medication).

Proportion of Americans Aged 55 and Older with Cognitive Impairment, by Race/Ethnicity, Health and Retirement Study, 2006*

Alzheimer's Disease by Race

More Resources

— "Special Report: Race, Ethnicity and Alzheimer’s Disease." Alzheimer's Association

— "African-Americans and Alzheimer's Disease: The Silent Epidemic." Alzheimer's Association. 

— "Hispanics/Latinos and Alzheimer's Disease." Alzheimer's Association. 

African Americans and Alzheimer's Disease: A study by North Carolina A&T State University and Duke University. 

— "The Shriver Report: A Woman's Nation Takes on Alzheimer's 2010." 

* Data compiled by Alzheimer's Association from Seshadri, S; Beiser, A; Kelly-Hayes, M; et al. “The lifetime risk of stroke: Estimates from the Framingham Study.” Stroke 2006;37:345–350.; and from Gurland, BJ; Wilder, DE; Lantigua, R; Stern, Y; Chen, J; Killeffer, EHP; et al. “Rates of dementia in three ethnoracial groups.” International Journal of Geriatric Psychiatry 1999;14:481–493.

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