Smokers are twice as likely to develop active tuberculosis (TB) compared to people who have never smoked, prompting a call for policymakers to be tougher on smoking.
One thirds of the world’s population is infected with TB, but 90 percent of these remain latent infections. The remaining 10 percent develop active TB at some point in their lives because of weak immune systems. For example, many people who are infected with HIV/AIDS fall sick and die from TB. TB continues to be a leading cause of death in the world. There were 9.3 million new cases of TB in 2007 and 1.8 million deaths. The World Health Organization aims to bring the incidence of TB down to one case per million each year by 2050.
Researchers studied 17,699 participants above 12 years of age in Taiwan to investigate the association between tobacco smoking and active tuberculosis in the general population. The participants were followed for three years. Out of 17,699 participants, 3,893 were current smokers, 552 were former smokers and 13,254 had never smoked. Data regarding the sex, age, living in a crowded home, household income, marital status, alcohol use and employment of participants was also collected.
Fifty-seven new cases of active TB were diagnosed at the end of the three-year follow-up. It was found that current smokers had a higher risk of developing active TB. Current smokers had a two-fold higher risk of active TB compared with those who had never smoked, and 17 percent of active TB cases in this population were due to smoking.
The researchers concluded that smokers have an impaired ability to fight infections, such as TB, and suggested policymakers and public health personnel to consider addressing tobacco cessation as part of tuberculosis control.