Smoking and TB deaths in India

Smoking is to blame for half the tuberculosis deaths among Indian men, according to new research, highlighting a neglected link between tobacco and the killer lung disease. Most big studies on smoking and health until now have been conducted in developed countries where tuberculosis (TB) has been relatively uncommon for more than half a century. As a result, the connection with TB, which is still endemic across much of Asia and Africa, has been greatly underestimated. The current study predicted that the number of men dying from smoking-related illnesses in India could double to more than a million a year by 2025. Three quarters of Indian male smokers who become ill with TB would not have done so if they had not smoked. The findings suggest that in some parts of the world the main way smoking kills is not via cancer and heart disease, but by damaging the lung's defenses against chronic TB infection.About a billion people worldwide are carrying viable TB bacilli in their lungs, but if they do not smoke then most will never become seriously ill. Smoking increases the danger that the infection will get out of control and cause clinical TB, which can spread easily to other people and also kill. TB causes about 1.6 million deaths worldwide each year, including more than a million in Asia and 400,000 in Africa.

Researchers from The Epidemiological Research Center in Chennai, India, compared the smoking habits of 43,000 men who had died of various diseases in the late 1990s with the habits of 35,000 living men. It was found that smokers were about four times as likely to become ill with TB as were non-smokers, and consequently four times as likely to die from the disease. It was estimated that almost 200,000 Indians die each year from TB because of smoking - half of them are still only in their 30s, 40s or early 50s. Smokers of both Western-style cigarettes and "bidis" - thin Indian cigarettes containing small amounts of tobacco wrapped in a greenish-brown leaf, face the same risk. India has more TB deaths than any other country. Overall, smoking currently causes some 700,000 deaths a year in India, 550,000 among men aged 25-69. The number of deaths could double by 2025 if current smoking patterns persist.

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