MONDAY, Aug. 24, 2009 (HealthDay News) -- Smokers are twice as likely as nonsmokers to develop active tuberculosis (TB), a new study shows.
Researchers analyzed data from nearly 17,000 people who took part in Taiwan's 2001 National Health Interview Survey. They found that current smokers had a 2.73 times higher risk of active TB than nonsmokers, while the risk for people who had smoked at some point in their lives was 2.69 times greater. After adjusting for other potential factors, the researchers determined that current smokers were two times more likely to develop active TB than nonsmokers.
They also found that younger smokers were more likely than smokers over age 65 to develop active TB, compared to nonsmokers.
The study appears in the Sept. 1 issue of the American Journal of Respiratory and Critical Care Medicine.
"The small number of TB cases in this study prevented us from examining the age-gradient of smoking-TB association at a finer age scale, and more studies are needed to confirm the findings," lead author Hsien-Ho Lin, a postdoctoral research fellow at Brigham and Women's Hospital in Boston, said in a journal news release.
"Because the baseline risk for active TB is higher in the elderly in many countries, a smaller but still elevated relative risk in this population may yet translate to a greater number of cases of active TB, and our findings should not be interpreted to mean that smoking poses a lower risk in the older population," said Lin.
Lin and colleagues said smoking's effects on different biological functions may increase the risk of active TB.
"To our knowledge, this is the first cohort study from a general population that provides evidence on the positive association between tobacco smoking and active TB," Lin said. "Based on results from ours and other studies, policy makers and public health personnel should consider addressing tobacco cessation as part of tuberculosis control. From the perspective of prevention, the target of smoking cessation should aim beyond TB patients to reach high-risk populations who are most likely to benefit from cessation."
The American Lung Association has more about TB.