Here’s another wow moment from the Alzheimer’s Association’s 2011 Alzheimer’s Disease Facts and Figures – “older African-Americans and Hispanics are proportionately more likely than older whites to have Alzheimer’s disease and other dementias.”
According to the report, older African-Americans are projected to be twice as likely to have Alzheimer’s and other dementias as older whites, while Hispanics are about one-and-one-half times as likely to have these diseases as older whites. Genetic factors are not believed to cause this difference across racial groups. Researchers instead point to the prevalence of health conditions such as high blood and diabetes are a factor for these groups. Additionally, lower levels of education and differences in socioeconomic characteristics that are risk factors are more commonly observed in older African-Americans and Hispanics.
Interestingly, researchers point to differences between the prevalence of dementia in U.S. minorities and their brethren in other parts of the world. “There seems to be something about living in a developed country,” said Dr. Patrick A. Griffith, Chief of the Division of Neurology at Morehouse School of Medicine on the Dana Foundation's website. “There is currently no consensus among researchers in the field about what may account for the higher prevalence and incidence of Alzheimer’s and dementia in ethnic minorities in the United States. Therefore, we learn from studies comparing similar groups outside the United States.” He pointed to an international study that compared a group of native Africans in Ibadan, Nigeria with a group of African-Americans in Indianapolis, Indiana. These researchers have found a lower prevalence of Alzheimer’s disease in the Ibadan participants. Another study also found a lower level of prevalence of Alzheimer’s in a cohort of native Africans in Ibadan who were studied along with two U.S. cohorts (one group of Hispanics and African-Americans in Manhattan and one group of African-Americans in Indianapolis). “These emerging data suggest that in developing countries the rate of dementia is low,” Dr. Griffith said. “There is something about how the disease develops in North America, England, Australia, and other developed countries that is different than how it develops in developing countries.”
Dr. Griffith believes the evidence suggests a combination of dietary, gene expression, and/or environmental factors are behind the increase in Alzheimer’s in African-Americans and U.S. Hispanics. He also noted that people in developing countries tend to be more physically active because they don’t have easy access to automobiles and public transportation.
Getting timely treatment is another challenge in relation to U.S. minorities. “Unfortunately, African-Americans and Hispanics tend to come to the attention of physicians only in the middle or later stages of the illness, when behavioral problems such as agitation, aggression, or wandering start to manifest,” Dr. Griffith said. “Whether this phenomenon of seeking treatment later than would be ideal is due to educational barriers, financial barriers, or cultural barriers is being debated. The cultural aspect is interesting, because in a lot of minority settings, the family may be more likely to ignore signs of forgetfulness, thinking that they are just a matter of getting older and not really a problem.”