Background
Tobacco is extracted from around 65 known species of the tobacco plant of which the one that is grown commercially and widely as a source of tobacco is Nicotiana tobaccum. Most of the tobacco from Northern India and Afghanistan comes from the species Nicotiana rustica. The growing use of tobacco is a cause of great concern around the world due to its serious effects on health.
Non-communicable diseases (NCDs) like ischemic heart diseases, cancers, diabetes, chronic respiratory diseases are the leading causes of death globally and associated with tobacco use. Available data from WHO demonstrate that thirty-eight million people die each year from NCDs, of which nearly 85% of NCD deaths occur in low- and middle-income countries.1
According to WHO statistics for 2010 in India, NCDs are estimated to account for 53% of all deaths. Of these deaths, cardiovascular diseases and diabetes are the most common causes of deaths in India.2 This huge burden of NCDs can be attributed to increasing use of tobacco. Tobacco is a major risk factor for a number of diseases affecting all age groups. WHO data shows that tobacco uses kill nearly six million people in a year. Around five million of those deaths are the result of direct tobacco use while more than 600,000 are the result of non-smokers being exposed to second-hand smoke. One person dies every six seconds due to tobacco. Up to half of current users will eventually die of a tobacco-related disease.3
The situation is equally bad in India with estimated number of tobacco users being 274.9 million where 163.7 million users of only smokeless tobacco, 68.9 million only smokers and 42.3 million users of both smoking and smokeless tobacco as per Global Adult Tobacco Survey India (GATS). It means around 35% of adults (47.9% males and 20.3% females) in India use tobacco in some form or the other. Use of smokeless tobacco is more prevalent in India (21%).4
Composition of tobacco
Tobacco products contains around 5000 toxic substances.5 Most important and dangerous constituents are:
Nicotine is the major cause of the predominant behavioral effects of tobacco. It is a poisonous substance leads to addiction. Nicotine influences and reinforces all tobacco-use behavior. After absorption, nicotine travels rapidly to the brain, in a matter of seconds, therefore, the psycho-active rewards associated with smoking occur quickly and these rewards are highly reinforced. Nicotine binds to the receptors in the brain where it influences the cerebral metabolism. Nicotine is then distributed throughout the body, mostly to skeletal muscles. Development of tolerance to its own actions is similar to that produced by other addictive drugs.
Carbon mono-oxide reduces the amount of oxygen blood can carry and causes shortness of breath. Tar is a sticky residue which contains benzopyrene, one of the deadliest cancer causing agents known. Other compounds are carbon dioxide, nitrogen oxides, ammonia, volatile nitrosamines, hydrogen cyanide, volatile sulfur containing compounds, volatile hydrocarbons, alcohols, aldehydes and ketones. Some of these compounds are known to cause cancers of various organs of the body.
Mechanism of action
Nicotine has structural similarity to a body neuro-transmitter acetylcholine (Ach) which conveys information from one neuron to another. Acetylcholine is an important neurotransmitter involved in systems concerned with mental and physical arousal, learning and memory, and several aspects of emotion. There are also other receptors for acetylcholine in the body, apart from the ones at synapses. They are also found at the junction of nerve and muscles and nerves and certain glands. Acetylcholine receptors throughout the body are traditionally classified as nicotine receptors (those that respond to nicotine) and muscarine receptors (those that respond to muscarine). The ability of nicotine to combine with acetylcholine-receptors means that it can exert actions like acetylcholine at all synapses where nicotine acetylcholine-receptors (nAChRs) are present and can trigger impulses.
Forms of tobacco intake
When non-smokers are exposed to smoke containing nicotine and toxic chemicals emitted by smokers it is called passive smoking or exposure to second hand smoke.
Risk factors for tobacco initiation
Following factors influence the predilection for tobacco use:
1.Biological:
2.Psychological:
Low emotional stability and risk taking behavior are more common in tobacco users. Existence of some mental disorders also increases the risk of tobacco use.
3.Social and Environmental:
Parental influence, lower education status, attraction towards role models, cultural practices, etc.
Consequences of tobacco use
Various effects of tobacco use are as follows:
Tobacco is considered as a major behavioral risk factor for non-communicable diseases one of the leading causes of death. Treatment of cardiovascular diseases and cancer imposes maximum financial burden on the individual and family. For cultivation of tobacco crop forests are destroyed. Burning of tobacco produces number of toxicants in environment. Manufacturing, packaging and transportation also cause environmental pollution.
Cancers associated with tobacco
Tobacco is also associated with cancer of respiratory tract, lung, upper gastrointestinal tract, liver, pancreas, kidney, urinary bladder, oral cavity, nasal cavity, cervix, etc. Smokeless tobacco (chew tobacco, snuff etc.) is a major cause of cancer of the oral cavity.
Risk of developing cancer increases with:
Cardiovascular diseases
Respiratory Diseases
Effect on pregnancy and its outcome
Effects on newborns and childhood
Maternal tobacco use during pregnancy and exposure of child to second hand smoke in childhood is known to be a risk factor for following conditions:
Miscellaneous
Following conditions are known to worsen if case of tobacco use:
Figure 1: Risks form smoking- Smoking can damage every part of the body
Source:
| This image is a work of the Centers for Disease Control and Prevention, part of the United States Department of Health and Human Services, taken or made as part of an employee's official duties. As a work of the U.S. federal government, the image is in the public domain. |
Therapy for tobacco cessation at the individual level
Therapy for tobacco-cessation can be broadly classified into two types: a) pharmacological and b) non-pharmacological.
A. Pharmacological:
Nicotine lozenge and sub-lingual tablets are also available as a form of nicotine replacement therapy. These devices increase quitting rates by approximately 1.5 to 2 times, regardless of setting.
2. Other Pharmacological Therapies: It includes anti depressants and symptomatic treatment. Pharmacological strategies have a useful role in alleviating withdrawal symptoms.
B. Behavioural treatment: There are number of techniques which can be used to manage the cessation of tobacco use.
Treating the Former Tobacco Users: Preventing Relapse to Tobacco Use
Effective relapse prevention treatment to all patients who have recently quit tobacco use needs to be provided. With the extraordinary high rate of relapse to smoking, patient’s decision to quit needs to be reinforced, benefits of quitting are reviewed, and the residual problems arising out of quitting need to be resolved. Minimal relapse prevention consists of congratulating success, encouraging continued abstinence, and discussing with the patient the benefits of quitting, the problems encountered during quitting and the anticipated challenges to staying abstinent
Tobacco control policies in India
Legislation
The Government of India enacted various legislations to control tobacco use. Recently the government enacted the Cigarettes and Other tobacco products (Prohibition of Advertisement and Regulation of Trade and Commerce, Production, Supply and Distribution) Act in 2003. The Act is applicable to all products containing tobacco in any form i.e. cigarettes, cigars, bidis, gutka, pan masala, khaini, snuff etc. The act has following sections:
Section 4: Bans Smoking in all “public places like Hotels restaurants, coffee houses, pubs, bars, airport lounges, and other such places visited by the general public, workplaces, shopping malls, cinema Halls, educational institutions and libraries, hospitals and auditorium, open auditorium, amusement centres, stadium, railway station, bus stop etc.
Section 5: It prohibits advertisement, promotion and sponsorship of all tobacco products; both direct and indirect advertisement of tobacco products is prohibited in all forms of audio, visual and print media. It imposes total ban on sponsoring of any sport and cultural events by cigarette and other tobacco product companies.
Section 6 (a): Prohibits sale of tobacco to minors (persons under the age of 18).
Section 6 (b): Prohibits sale of tobacco products near educational institutions. Sale of any tobacco product is prohibited in an area within radius of 100 yards of any educational institution
Section 7: Its calls for specified health warning labels on all tobacco products.
Section 7 (5): Every tobacco package must have nicotine and tar contents along with maximum permissible limits. Specified warning should be there depicted on tobacco package.7
Tobacco Free Initiative in India
One important initiative under this is setting up of Tobacco Cessation Clinics in India. During 2001-02, 13 Tobacco Cessation Clinics were set-up in 12 states across the country in settings such as cancer treatment hospitals, psychiatric hospitals, medical colleges, NGOs etc users to quit tobacco use.
National Guidelines for Treatment of Tobacco Dependence have also been developed and disseminated by the Government in 2011, to facilitate training of health professionals in tobacco cessation.8 Various interventions and research studies were also supported to develop community based tobacco cessation models.
National Tobacco Control Program
The National Tobacco Control Program was launched by Ministry of Health and Family Welfare, Government of India in 2007- 08 to bring about greater awareness about the harmful effects of tobacco use and tobacco Control Laws as well as to facilitate effective implementation of the tobacco Control Laws. The National Tobacco Control Cell (NTCC) is responsible for overall policy formulation, planning, monitoring and evaluation of the different activities. National level public awareness/mass media campaigns for awareness building and behavioural change are planned to be carried out.
The content of this module has been validated by Prof. Jugal Kishore, Department of Community Medicine, Maulana Azad Medical College on 27/10/2014
References
