Dementia and Alzheimer’s disease: a comparative study of Americans and Africans
This study (JAMA 2001;285 (6):796-8) followed two groups of men and women aged 65 and over for about five years. The first group was made up of African-Americans from Indianapolis and the second group was composed of Africans living in Nigeria. At the end of the study, after adjusting for all other variables, the American group proved to have more than double the rate of Alzheimer’s disease and other types of dementia than the African group. This study again suggests that dementia is an environmental rather than a genetic disorder.