African-Americans who smoke a little more than a pack of cigarettes a day are at higher risk for lung cancer than whites and other ethnic groups who smoke the same amount, a new study released today concludes.
The disparity, researchers suggest, could be caused by anything from genetics to differences in how nicotine is metabolized by different racial and ethnic groups.
“We don’t know the real reason for these differences. It could be due to societal, cultural or environmental factors that we don’t know about in these populations, and we can’t rule out the role genetics may play in the differences as well,” said lead author Christopher Haiman, an assistant professor in preventive medicine at the University of Southern California.
The increased risk of lung cancer was seen only in individuals who smoked no more than 30 cigarettes a day. An average pack contains about 20 cigarettes.
Among heavy smokers, the racial differences were not considered statistically significant.
Haiman noted that the differences in risk among racial and ethnic groups could not be explained away by socioeconomic factors such as occupation or education.
“For future research it would be interesting to identify the underlying environmental and susceptibility factors that might contribute to the differences,” he said.
It has been known for many years that blacks are substantially more likely than whites to develop lung cancer and are more likely to die from it. While some have hypothesized that the difference is a matter of genetics, others have pointed to smoking habits.