Race and Venous Thromboembolism
Nature or Nurture?
Conventional teaching is that a racial gradient exists for the frequency of venous thromboembolism (VTE) in the United States. Asian Americans have the lowest risk, and blacks have the highest risk. Hispanic Americans and Americans of European ancestry have an intermediate risk, with Hispanic Americans having less frequent VTE than those of European but non-Hispanic heritage. The most apparent paradox is that blacks have the highest rate of VTE, even though they rarely carry the prothrombin gene mutation or factor V Leiden mutation, 2 genetic abnormalities that predispose to VTE. Based on genetic profiling (nature), one might have predicted that blacks would have a low rate of VTE. In 1 study, in comparison with individuals of European ancestry and adjusting for age and sex, blacks had a 30% to 60% higher incidence of VTE than European Americans.1 This finding suggests that environmental and socioeconomic factors and perhaps healthcare disparities (nurture) play an important role in determining the risk of developing VTE.
Article see p 1502
In New York City, 578 consecutive out-of-hospital fatal pulmonary embolism (PE) cases were investigated by the Office of the Chief Medical Examiner.2 All underwent autopsy, toxicology, microbiology, and genetic testing. Race-adjusted incidence rates per 100 000 people per year were as follows: blacks 3.73, whites, 1.15, and Hispanics, 0.93. The percentage of PE deaths in comparison with the New York City population was as follows: blacks (58% versus 25%), whites (25% versus 35%), and Hispanics (16% versus 28%). Obesity was 2.5- to 3-fold higher in fatal PE cases than in the New York City population as a whole.
The observation of race correlating with VTE frequency has been accepted with little disagreement or critique. One compelling cross-sectional study challenges existing dogma and shows that the topic is far more complex than initially thought. …