African-Americans More Likely to Develop Alzheimer’s Disease than Caucasians

Scientists have known for a long time that Alzheimer’s disease is more prevalent in the African-American population than in Caucasians or other groups. For the first time, researchers from Emory University have quantified that disparity in a meta-analysis that was published in the Journal of Alzheimer’s Disease on Jan. 5, 2016

A 64 Percent Higher Incidence

The team of researchers from Emory’s Alzheimer’s Disease Research Center analyzed data from six different studies to determine prevalence by race. They found a 64 percent higher incidence among the African-American population after adjusting for age, gender and education. The estimated Alzheimer’s Disease rate among Caucasians age 65–90 was 5.5 percent, versus a much higher 8.6 percent for African-Americans.

According to lead author Kyle Steenland, professor of environmental health and epidemiology, this research is just a starting point. “We wanted to come up with an overall estimate of racial differences to help motivate further exploration of possible causes, such as biological, psychological and socioeconomic factors,” he said.  

A Complex Issue

The prevalence of Alzheimer’s disease in the African-American population is a complicated issue. Culturally, African-Americans and Hispanics are more likely to consider dementia a normal symptom of aging, so they are less likely to seek treatment. Furthermore, African-Americans are far less likely to participate in medical studies and clinical trials due to a history of abuses; for example, the Tuskegee Syphilis Experiment in 1932 left 400 low-income black men suffering from syphilis untreated even after penicillin became available. Many African-Americans are mistrustful of medial research as a result of this history of abuse, which makes it more difficult to collect accurate data. 

Next Steps for Researchers

Steenland also stated that the demographic information could be important in projecting the expected rates of Alzheimer’s in the future, as the U.S. population is both aging and shifting in its racial makeup. By 2045, Caucasians are expected to no longer make up the majority of the U.S. population, so racial discrepancies in disease rates could skew projections quite a bit as our population ages. This new data will help scientists predict Alzheimer’s disease rates more accurately.

This analysis only compiled data from other studies to establish a correlation between race and disease rate. It’s not clear whether the higher rate of Alzheimer’s disease among African-Americans is caused by genetic or environmental factors, and in fact, the researchers stated in the study’s abstract that it “raises important etiologic questions regarding factors responsible for this discrepancy.”