DR SEEMA DWIVEDI
In 2017, the World Health Organisation (WHO) described tobacco as “the world’s single biggest cause of preventable death”. Cigarettes cause most of the harm that tobacco does. A monograph of the US National Cancer Institute and WHO notes that manufactured cigarettes account for 92.3 per cent of tobacco sales worldwide. It concludes that they are “responsible for the vast majority of tobacco-caused disease and death”.
The Global Burden of Disease study, published in The Lancet in 2021, estimated 7.69 million deaths from smoking across the world in 2019. It found smoking to be the leading risk factor for death among males, accounting for 20.2 per cent of male deaths. The US Surgeon General’s report of 2014 attributes more than 20 million premature deaths in the United States to cigarette smoking since 1964.
India’s heavy burden
India carries a heavy share of the world’s burden. The Global Burden of Disease study found that deaths from smoking in India rose from 0.6 million in 1990 to 1.0 million in 2019. It named India among the three countries with the largest rise in the number of such deaths.
In 2008, Prabhat Jha and his colleagues published a nationally representative study of smoking and death in India in The New England Journal of Medicine. They estimated that smoking would cause about 930,000 adult deaths in India in 2010. That is more than 2,500 deaths every day.
The science on cause and effect is more than sixty years old. In 1964, the US Surgeon General’s Advisory Committee on Smoking and Health concluded: “Cigarette smoking is causally related to lung cancer in men; the magnitude of the effect of cigarette smoking far outweighs all other factors.”
The Surgeon General’s report of 2014 records that cigarette smoking has been causally linked to “diseases of nearly all organs of the body”. That report added diabetes, colorectal cancer, liver cancer, tuberculosis, erectile dysfunction, rheumatoid arthritis and impaired immune function to the list.
A cigarette stick burns out in a few minutes; the harm it starts does not. This is the first part of the three-part series on the cigarette that follows the smoke into the smoker’s body and mind. The second will turn to the family, and the third to the cost to the nation
The International Agency for Research on Cancer has classified tobacco smoking in Group 1, as “carcinogenic to humans”. Its list of cancers caused by smoking includes cancers of the lung, mouth, throat, voice box, food pipe, stomach, pancreas, bowel, liver, kidney, bladder and cervix, and myeloid leukaemia.
Introducing the 2010 report, the Surgeon General, Dr Regina Benjamin, wrote that a smoker inhales “more than 7,000 chemicals: hundreds of these are hazardous, and at least 69 are known to cause cancer”. The report concludes that the smoke causes disease “through mechanisms that include DNA damage, inflammation, and oxidative stress”.
TB disease stands out
In India, one disease stands out: tuberculosis. Jha’s study found that the excess deaths among smokers came chiefly from tuberculosis, and from respiratory and vascular disease and cancer. Among people aged 30 to 69, men who smoked faced 2.3 times the risk of death from tuberculosis that men who did not smoke faced. For women who smoked, the risk was 3.0 times that of women who did not. The Union Health Ministry’s 2004 report on tobacco control states that smoking “contributes to half the male deaths from TB in India”.
The same report, summarising Indian studies, states that about a quarter of all persistent smokers of cigarettes or bidis in India are killed by tobacco before the age of 70. They lose about 20 years of life expectancy. It adds that a third of the deaths caused by smoking are from vascular disease, and half are from tuberculosis or other respiratory diseases.
THE SMOKER : What the cigarette does to the person who lights it
Other Indian evidence points the same way. The Health Ministry’s 2022 report notes cohort studies from Mumbai and Thiruvananthapuram, which found that smokers have 31 to 55 per cent higher risks of premature death than non-smokers.
There is no safe number of sticks. The 2010 Surgeon General’s report concludes that “there is no risk-free level of exposure to tobacco smoke”. In India, Jha’s study found that “daily smoking of even a small amount of tobacco was associated with increased mortality.”
The filter does not change this. The 2010 report found that changes in cigarette design, including filtered, low-tar and ‘light’ variations, “have not reduced overall disease risk among smokers”.
Toll on years, lives
Smoking takes years as well as lives. Jha’s study found that smoking was associated with a loss of eight years of median survival for women and six years for men. The authors estimated that if the link is mainly causal, smoking accounts for about one in five deaths of men aged 30 to 69 in India.
Richard Doll, Richard Peto and their colleagues followed 34,439 male British doctors for 50 years. Men born between 1900 and 1930 who smoked only cigarettes and kept smoking “died on average about 10 years younger than lifelong non-smokers”. For these continuing smokers, the eventual risk of being killed by their habit ranged from about one half to about two thirds. The authors note that the higher figure applies directly only to these doctors. The Surgeon General’s report of 2014 states that smokers “are estimated to lose more than a decade of life”.
Why do smokers carry on? The cigarette delivers a drug. In 1988 the Surgeon General’s report on nicotine addiction concluded that “Cigarettes and other forms of tobacco are addicting” and that “Nicotine is the drug in tobacco that causes addiction”. The same report found that the processes that determine tobacco addiction are similar to those that determine addiction to “drugs such as heroin and cocaine”. Dr Benjamin’s preface to the 2010 report adds that one-third of the people who ever try smoking become daily smokers.
Indian data shows the grip. GATS 2 (the second round of the Global Adult Tobacco Survey) found that 58.5 per cent of daily users of tobacco in any form take their first tobacco within 30 minutes of waking up. Of the cigarette smokers who tried to quit in the past year, 47.4 per cent could not stay off cigarettes for even a month. GATS 2 found that 83.0 per cent of cigarette smokers noticed the health warning on the packet. Yet 47.9 per cent of all smokers, bidi smokers included, told the survey that smoking had not harmed their body.
Mental health link
Smoking is also tied to mental health. In 2013, the Royal College of Physicians and the Royal College of Psychiatrists in Britain published a joint report on smoking and mental health. They found that smoking is “around twice as common among people with mental disorders”. They said that current smoking is associated with an increased risk of the onset of depression and of anxiety disorders. The colleges noted that the symptoms of mental disorders can be confused with those of nicotine withdrawal. A cigarette that eases withdrawal can then seem to ease the disorder.
A systematic review in the British Medical Journal in 2014 looked at what happens when smokers stop. It found that quitting is associated with “reduced depression, anxiety, and stress and improved positive mood and quality of life compared with continuing to smoke”. It found effects “equal or larger than those of antidepressant treatment for mood and anxiety disorders”.
Smoking wears down the body long before it kills. The Surgeon General’s report of 2014 records that smokers suffer poorer general health than non-smokers, “beginning at an early age and extending throughout adult life”. The report also names smoking as a cause of age-related macular degeneration, an eye disease that can lead to loss of central vision. It names smoking as a cause of ectopic pregnancy too, which it calls “a potentially fatal condition for the mother”.
THE WAY OUT
There is a way out. The British doctors study found that stopping at 60, 50, 40 or 30 years of age gained about 3, 6, 9 or 10 years of life expectancy. Among the men born around 1920, prolonged cigarette smoking from early adult life tripled the death rate at each age. Stopping at 50 halved that hazard, and stopping at 30 “avoided almost all of it”.
More than half of India’s smokers want to stop. GATS 2 found that 55.4 per cent of smokers are interested in quitting or planning to quit. Of the smokers who tried to quit in the past year, 71.7 per cent used no formal method of quitting.
The harm builds stick by stick, drag by drag. The evidence is just as clear that the sooner smokers put out their last stick, the more years they win back. But the smoker is not the only person who breathes the smoke. The next story in this series turns to the family.
The Global Burden of Disease study found that deaths from smoking in India rose from 0.6 million in 1990 to 1.0 million in 2019. It named India among the three countries with the largest rise in the number of such deaths
Among people aged 30 to 69, men who smoked faced 2.3 times the risk of death from tuberculosis that men who did not smoke faced. For women who smoked, the risk was 3.0 times that of women who did not.
