Environmental and potentially preventable factors may be the cause of racial disparities in high blood pressure. Previous studies have implicated genetic factors. The current study, reported in BMC Medicine (January 5, 2005), compared the rates of hypertension between African Americans and Caucasians in different populations. The population included blacks in Nigeria, Jamaica, and the United States. For Caucasians, populations in the United States, Canada, and 5 European countries were examined.
If racial origin played a significant role in high blood pressure, then rates for each race would be expected to be about the same no matter where the individuals resided. The researchers, however, found wide variation in rates ranging from 14% for African Americans in some geographic regions to 44% in other places. In the Caucasian populations, the rates ranged from 27% to 55%, depending on the individual's location.
Specifically, the lowest rate of high blood pressure (13.5%) was among blacks in Nigeria, while the highest (55.3%) was among Caucasians in Germany. The African American population had higher rates for individuals living in more industrialized places. The study found Nigerians had a rate of 13.5%, Jamaicans had a rate of 28.6%, and blacks in the United States had a rate of 44%.