Smoking cessation (colloquially quitting smoking) is the process of discontinuing tobacco smoking. Tobacco contains nicotine, which is addictive.[1]
Smoking cessation can be achieved with or without assistance from healthcare professionals or the use of medications.[2] Methods that have been found to be effective include interventions directed at or via health care providers and health care systems; medications including nicotine replacement therapy (NRT) and varenicline; individual and group counselling; and Web-based or stand-alone and computer programs. Although stopping smoking can cause short-term side effects such as reversible weight gain, smoking cessation services and activities are cost-effective because of the positive health benefits.
- In a growing number of countries, there are more ex-smokers than smokers.[2]
- Early "failure" is a normal part of trying to stop, and more than one attempt at stopping smoking prior to longer-term success is common.[2]
- NRT, other prescribed pharmaceuticals, and professional counselling or support also help many smokers.[2]
- However, up to three-quarters of ex-smokers report having quit without assistance ("cold turkey" or cut down then quit), and cessation without professional support or medication may be the most common method used by ex-smokers.[2]
Tobacco contains nicotine. Smoking cigarettes can lead to nicotine addiction.[3]:2300–2301 The addiction begins when nicotine acts on nicotinic acetylcholine receptors to releaseneurotransmitters such as dopamine, glutamate, and gamma-aminobutyric acid.[3]:2296 Cessation of smoking leads to symptoms of nicotine withdrawal such as anxiety and irritability.[3]:2298Professional smoking cessation support methods generally endeavour to address both nicotine addiction and nicotine withdrawal symptoms.
Studies have shown that it takes between 6 to 12 weeks post quitting before the amount of nicotinic receptors in the brain return to the level of a non smoker.[4]
Major reviews of the scientific literature on smoking cessation include:
Methods[edit]
- Systematic reviews of the Cochrane Tobacco Addiction Group of the Cochrane Collaboration.[5] As of 2012, this independent, international, not-for-profit organization has published over 60 systematic reviews "on interventions to prevent and treat tobacco addiction"[5] which will be referred to as "Cochrane reviews."
- Clinical Practice Guideline: Treating Tobacco Use and Dependence: 2008 Update of the United States Department of Health and Human Services, which will be referred to as the "2008 Guideline."[6] The Guideline was originally published in 1996[7] and revised in 2000.[8] For the 2008 Guideline, experts screened over 8700 research articles published between 1975 and 2007.[6]:13–14 More than 300 studies were used in meta-analyses of relevant treatments; an additional 600 reports were not included in meta-analyses, but helped formulate the recommendations.[6]:22 Limitations of the 2008 Guideline include its not evaluating studies of "cold turkey" methods ("unaided quit attempts") and its focus on studies that followed up subjects only to about 6 months after the "quit date" (even though almost one-third of former smokers who relapse before one year will do so 7–12 months after the "quit date").[6]:19,23[9][10]
Unassisted methods[edit]
As it is common for ex-smokers to have made a number of attempts (often using different approaches on each occasion) to stop smoking before achieving long-term abstinence, identifying which approach or technique is eventually most successful is difficult; it has been estimated, for example, that "only about 4% to 7% of people are able to quit smoking on any given attempt without medicines or other help.".[11] However, in analysing a 1986 U.S. survey, Fiore et al. (1990) found that 95% of former smokers who had been abstinent for 1–10 years had made an unassisted last quit attempt.[12] The most frequent unassisted methods were "cold turkey" and "gradually decreased number" of cigarettes.[12] A 1995 meta-analysis estimated that the quit rate from unaided methods was 7.3% after an average of 10 months of follow-up.[13]
Cold turkey[edit]
"Cold turkey" is a colloquial term indicating abrupt withdrawal from an addictive drug, and in this context indicates sudden and complete cessation of all nicotine use. In three studies, it was the quitting method cited by 76%,[14] 85%,[12] or 88%[15] of long-term successful quitters. In a large British study of ex-smokers in the 1980s, before the advent of pharmacotherapy, 53% of the ex-smokers said that it was "not at all difficult" to stop, 27% said it was "fairly difficult", and the remaining 20% found it very difficult.[2] Cold turkey methods have been advanced by J. Wayne McFarland and Elman J. Folkenburg;[16][17] Joel Spitzer and John R. Polito;[18] and Allen Carr.[19]
Healthcare provider and systems[edit]
Interventions delivered via healthcare providers and healthcare systems have been shown to improve smoking cessation among people who visit those providers.
- A clinic screening system (e.g., computer prompts) to identify whether or not a person smokes doubled abstinence rates, from 3.1% to 6.4%.[6]:78–79 Similarly, the Task Force on Community Preventive Services determined that provider reminders alone or with provider education are effective in promoting smoking cessation.[20]:33–38
- A 2008 Guideline meta-analysis estimated that physician advice to quit smoking led to a quit rate of 10.2%, as opposed to a quit rate of 7.9% among patients who did not receive physician advice to quit smoking.[6]:82–83 A Cochrane review found that even brief advice from physicians had "a small effect on cessation rates."[21] However, one study from Ireland involving vignettesfound that physicians' probability of giving smoking cessation advice declines with the patient's age,[22] and another study from the U.S. found that only 81% of smokers age 50 or greater received advice on quitting from their physicians in the preceding year.[23]
- For one-to-one or person-to-person counselling sessions, the duration of each session, the total amount of contact time, and the number of sessions all correlated with the effectiveness of smoking cessation. For example, "Higher intensity" interventions (>10 minutes) produced a quit rate of 22.1% as opposed to 10.9% for "no contact"; over 300 minutes of contact time produced a quit rate of 25.5% as opposed to 11.0% for "no minutes"; and more than 8 sessions produced a quit rate of 24.7% as opposed to 12.4% for 0–1 sessions.[6]:83–86
- Both physicians and non-physicians increased abstinence rates compared with self-help or no clinicians.[6]:87–88 For example, a Cochrane review of 31 studies found that nursing interventions increased the likelihood of quitting by 28%.[24]
- Dental professionals also provide a key component in increasing tobacco abstinence rates in the community through counseling patients on the effects of tobacco on oral health in conjunction with an oral exam.[25]
- According to the 2008 Guideline, based on two studies the training of clinicians in smoking cessation methods may increase abstinence rates[6]:130; however, a Cochrane review found "a measurable effect" that such training decreased smoking in patients.[26]
- Reducing or eliminating the costs of cessation therapies for smokers increased quit rates in three meta-analyses.[6]:139–140[20]:38–40[27]
- In one systematic review and meta-analysis, multi-component interventions increased quit rates in primary care settings.[28] "Multi-component" interventions were defined as those that combined two or more of the following strategies known as the "5 A's"[6]:38–43:
- Ask — Systematically identify all tobacco users at every visit
- Advise — Strongly urge all tobacco users to quit
- Assess — Determine willingness to make a quit attempt
- Assist — Aid the patient in quitting (provide counselling-style support and medication)
- Arrange — Ensure follow-up contact
Biochemical feedback[edit]
Various methods exist which allow a smoker to see the impact of their tobacco use, and the immediate effects of quitting. Using biochemical feedback methods can allow tobacco-users to be identified and assessed, and the use of monitoring throughout an effort to quit can increase motivation to quit.[29][30]
- Breath carbon monoxide (CO) monitoring: Because carbon monoxide is a significant component of cigarette smoke, a breath carbon monoxide monitor can be used to detect recent cigarette use. Carbon monoxide concentration in breath has been shown to be directly correlated with the CO concentration in blood, known as percent carboxyhemoglobin. The value of demonstrating blood CO concentration to a smoker through a non-invasive breath sample is that it links the smoking habit with the physiological harm associated with smoking.[31] Within hours of quitting, CO concentrations show a noticeable decrease, and this can be encouraging for someone working to quit. Breath CO monitoring has been utilized in smoking cessation as a tool to provide patients with biomarker feedback, similar to the way in which other diagnostic tools such as the stethoscope, the blood pressure cuff, and the cholesterol test have been used by treatment professionals in medicine.[29]
- Cotinine: A metabolite of nicotine, cotinine is present in smokers. Like carbon monoxide, a cotinine test can serve as a reliable biomarker to determine smoking status.[32] Cotinine levels can be tested through urine, saliva, blood, or hair samples, with one of the main concerns of cotinine testing being the invasiveness of typical sampling methods.
While both measures offer high sensitivity and specificity, they differ in usage method and cost. As an example, breath CO monitoring is non-invasive, while cotinine testing relies on a bodily fluid. These two methods can be used either alone or together, for example, in a situation where abstinence verification needs additional confirmation.[33]
Single medications[edit]
The American Cancer Society estimates that "between about 25% and 33% of smokers who use medicines can stay smoke-free for over 6 months."[11]Single medications include:
- Nicotine replacement therapy (NRT): Five medications approved by the U.S. Food and Drug Administration (FDA) deliver nicotine in a form that does not involve the risks of smoking. NTRs are meant to be used for a short period of time and should be tapered down to a low dose before stopping. The five NRT medications, which in a Cochrane review increased the chances of stopping smoking by 50 to 70% compared to placebo or to no treatment,[34] are:
- transdermal nicotine patches deliver doses of the addictive chemical nicotine, thus reducing the unpleasant effects of nicotine withdrawal. These patches can give smaller and smaller doses of nicotine, slowly reducing dependence upon nicotine and thus tobacco. A Cochrane review found further increased chance of success in a combination of the nicotine patch and a faster acting form.[34] Also, this method becomes most effective when combined with other medication and psychological support.[35]
- gum
- lozenges
- sprays
- inhalers.
- A study found that 93 percent of over-the-counter NRT users relapse and return to smoking within six months.[36]
- Antidepressant: Bupropion is FDA-approved and is marketed under the brand name Zyban. Bupropion is contraindicated in epilepsy, seizure disorder; anorexia/bulimia (eating disorders), patients' use of antidepressant drugs (MAO inhibitors) within 14 days, patients undergoing abrupt discontinuation of ethanol or sedatives (including benzodiazepines such as Valium).[37][38]
- Nicotinic receptor partial agonists:
- Cytisine (Tabex) is a plant extract that has been in use since the 1960s in former Soviet-bloc countries.[39] It was the first medication approved as an aid to smoking cessation, and has very few side effects in small doses.[40][41]:70
- Varenicline tartrate is a prescription drug marketed by Pfizer as Chantix in the U.S. (under FDA approval) and as Champix outside the U.S.[42] Synthesized as an improvement upon cytisine,[43] varenicline decreases the urge to smoke and reduces withdrawal symptoms.[44] Two systematic reviews and meta-analyses supported by unrestricted funding from Pfizer, one in 2006[45] and one in 2009,[46] found varenicline more effective than NRT or bupropion. A table in the 2008 Guideline indicates that 2 mg/day of varenicline leads to the highest abstinence rate (33.2%) of any single therapy, while 1 mg/day leads to an abstinence rate of 25.4%.[6]:109 A 2011 Cochrane review of 15 studies (13 of which had been sponsored by Pfizer) found that varenicline was significantly superior to bupropion at one year but that varenicline and nicotine patches produced the same level of abstinence at 24 weeks.[47] A 2011 review of double-blind studies found that varenicline has increased risk of serious adverse cardiovascular events compared with placebo.[48] Varenicline may cause neuropsychiatric side effects; for example, in 2008 the UK. Medicines and Healthcare products Regulatory Agency issued a warning about possible suicidal thoughts and suicidal behavior associated with varenicline.[49]
- Moclobemide has been tested in heavy dependent smokers against placebo based on the theory that tobacco smoking could be a form of self medicating of major depression,[50] and moclobemide could therefore help increase abstinence rates due to moclobemide mimicking the MAO-A inhibiting effects of tobacco smoke. Moclobemide was administered for 3 months and then stopped; at 6 months follow-up it was found those who had taken moclobemide for 3 months had a much higher successful quit rate than those in the placebo group. However, at 12 month follow-up the difference between the placebo group and the moclobemide group was no longer significant.[51]
Two other medications have been used in trials for smoking cessation, although they are not approved by the FDA for this purpose. They may be used under careful physician supervision if the first line medications are contraindicated for the patient.
- Clonidine may reduce withdrawal symptoms and "approximately doubles abstinence rates when compared to a placebo," but its side effects include dry mouth and sedation, and abruptly stopping the drug can cause high blood pressure and other side effects.[6]:55,116–117[52]
- Nortriptyline, another antidepressant, has similar success rates to bupropion but has side effects including dry mouth and sedation.[6]:56,117–118[38]
Combinations of medications[edit]
The 2008 US Guideline specifies that three combinations of medications are effective[6]:118–120:
- Long-term nicotine patch and ad libitum NRT gum or spray
- Nicotine patch and nicotine inhaler
- Nicotine patch and bupropion (the only combination that the US FDA has approved for smoking cessation)
Cut down to quit[edit]
Gradual reduction involves slowly reducing one's daily intake of nicotine. This can theoretically be accomplished through repeated changes to cigarettes with lower levels of nicotine, by gradually reducing the number of cigarettes smoked each day, or by smoking only a fraction of a cigarette on each occasion. A 2009 systematic review by researchers at the University of Birminghamfound that gradual nicotine replacement therapy could be effective in smoking cessation.[53][54] A 2010 Cochrane review found that abrupt cessation and gradual reduction with pre-quit NRTproduced similar quit rates whether or not pharmacotherapy or psychological support was used. [55][56] According to a more recent 2012 Cochrane systematic review analysis of 10 studies and 3670 patients, overall relative risk reduction between smokers who attempted to quit with abrupt cessation or with gradual reduction techniques was 0.06. This analysis demonstrated that there was no significant difference in quit rates between smokers who quit by gradual reduction or abrupt cessation as measured by abstinence from smoking of at least six months from the quit day, suggesting that patients who want to quit can choose between these two methods.[57]
Community interventions[edit]
A Cochrane review found evidence that community interventions using "multiple channels to provide reinforcement, support and norms for not smoking" had an effect on smoking cessation outcomes among adults.[58] Specific methods used in the community to encourage smoking cessation among adults include:
- Policies making workplaces[14] and public places smoke-free. It is estimated that "comprehensive clean indoor laws" can increase smoking cessation rates by 12%–38%.[59] In 2008, the New York State of Alcoholism and Substantance Abuse Services banned smoking by patients, staff and volunteers at 1,300 addiction treatment centers.[60]
- Voluntary rules making homes smoke-free, which are thought to promote smoking cessation.[14][61]
- Initiatives to educate the public regarding the health effects of second-hand smoke.
- Increasing the price of tobacco products, for example by taxation. The US Task Force on Community Preventive Services found "strong scientific evidence" that this is effective in increasing tobacco use cessation.[20]:28–30 It is estimated that an increase in price of 10% will increase smoking cessation rates by 3–5%.[59]
- Mass media campaigns. The US Task Force on Community Preventive Services declared that "strong scientific evidence" existed for these when "combined with other interventions"[20]:30–32, but a Cochrane review concluded that it was "difficult to establish their independent role and value".[62]
Competitions and incentives[edit]
One 2008 Cochrane review concluded that "incentives and competitions have not been shown to enhance long-term cessation rates."[63] However, a trial published in 2009 found that financial incentives for smoking cessation led to significantly higher rates of smoking cessation 15–18 months after enrollment.[64] Furthermore, a different 2008 Cochrane review found that one type of competition, "Quit and Win," did increase quit rates among participants.[65]
Psychosocial approaches[edit]
- Great American Smokeout is an annual event that invites smokers to quit for one day, hoping they will be able to extend this forever.
- The World Health Organization's World No Tobacco Day is held on May 31 each year.
- Smoking-cessation support is often offered over the internet, over the telephone quitlines[66][67] (e.g., the US toll-free number 1-800-QUIT-NOW), or in person. Three meta-analyses have concluded that telephone cessation support is effective when compared with minimal or no counselling or self-help, and that telephone cessation support with medication is more effective than medication alone.[6]:91–92[20]:40–42[68]
- Group or individual psychological support can help people who want to quit. This form of counselling can be effective alone; combining it with medication is more effective, and the number of sessions of support with medication correlates with effectiveness.[6]:89–90,101–103[69][70] The counselling styles that have been effective in smoking cessation activities include motivational interviewing,[71][72][73] cognitive behavioural therapy[74] and Acceptance and Commitment Therapy.[75][75]
- The Freedom From Smoking group clinic includes eight sessions and features a step-by-step plan for quitting smoking. Each session is designed to help smokers gain control over their behavior. The clinic format encourages participants to work on the process and problems of quitting both individually and as part of a group[76]
- Multiple formats of psychosocial interventions increase quit rates: 10.8% for no intervention, 15.1% for one format, 18.5% for 2 formats, and 23.2% for three or four formats.[6]:91
- The Transtheoretical Model including "stages of change" has been used in tailoring smoking cessation methods to individuals.[77][78][79][80] However, a 2010 Cochrane review concluded that "stage-based self-help interventions (expert systems and/or tailored materials) and individual counselling were neither more nor less effective than their non-stage-based equivalents."[81]
Self-help[edit]
A 2005 Cochrane review found that self-help materials may produce only a small increase in quit rates.[82] In the 2008 Guideline, "the effect of self-help was weak," and the number of types of self-help did not produce higher abstinence rates.[6]:89–91 Nevertheless, self-help modalities for smoking cessation include:
- In-person self-help groups such as Nicotine Anonymous[83][84] or electronic self-help groups such as Stomp It Out.[85]
- Newsgroups: The Usenet group alt.support.stop-smoking has been used by people quitting smoking as a place to go to for support from others.[86] It is accessible through Google Groups.[87]and is now also available as an online forum, at http://www.as3-web.org/discuss .
- Interactive web-based and stand-alone computer programs and online communities which assist participants in quitting, such as EX and QuitNet. For example, "quit meters" keep track of statistics such as how long a person has remained abstinent.[88] In the 2008 US Guideline, there was no meta-analysis of computerised interventions, but they were described as "highly promising."[6]:93–94 A meta-analysis published in 2009,[89] a Cochrane review published in 2010,[90] and a 2011 systematic review[91] found the evidence base for such interventions weak.
- Mobile phone-based interventions: A 2009 Cochrane review stated that "more evidence is needed" to determine the effectiveness of such interventions.[92] As of 2009, a randomised trial of mobile phone-based smoking cessation support was underway in the UK.[93]
- Self-help books such as Allen Carr's Easy Way to Stop Smoking.[19]
- Spirituality: In one survey of adult smokers, 88% reported a history of spiritual practice or belief, and of those more than three-quarters were of the opinion that using spiritual resources may help them quit smoking.[94]
Substitutes for cigarettes[edit]
- Electronic cigarette: Shaped like a cigarette to emulate the tactile experience of smoking, electronic cigarettes contain a rechargeable battery and a heating element which vaporises liquid nicotine and other flavorings from an insertable cartridge. Proponents of electronic cigarettes often market them as a smoking cessation device. Many claim that electronic cigarettes deliver the experience of smoking without the adverse health effects usually associated with tobacco smoke, or at least greatly reduce those risks.[95] However, in September 2008, the World Health Organization issued a release proclaiming that it does not consider the electronic cigarette to be a legitimate smoking cessation aid, stating that "no rigorous, peer-reviewed studies have been conducted showing that the electronic cigarette is a safe and effective nicotine replacement therapy."[96]
- The US National Institute of Health recommends chewing cinnamon sticks when trying to quit the use of tobacco. In addition to raw cinnamon sticks, cinnamon-flavoured toothpicks are used to help curb the urge for tobacco.[97][98]
- Plastic cigarette substitute: In one 2006 study, giving people a free "Better Quit" hollow tube resembling a cigarette did not improve quit rates.[99]
Alternative approaches[edit]
- Acupuncture: Acupuncture has been explored as an adjunct treatment method for smoking cessation.[100] A Cochrane review concluded that acupuncture "do[es] not appear to help smokers who are trying to quit",[101] a meta-analysis from the 2008 Guideline showed no difference between acupuncture and placebo,[6]:99–100 and the 2008 Guideline found no scientific studies supporting laser therapy based on acupuncture principles but without the needles.[6]:99
- Aromatherapy: A 2006 book reviewing the scientific literature on aromatherapy[102] identified only one study on smoking cessation and aromatherapy; the study found that "inhalation of vapor from black pepper extract reduces smoking withdrawal symptoms".[103]
- Hypnosis: Hypnosis often involves the hypnotherapist suggesting to the patient the unpleasant outcomes of smoking.[104] Clinical trials studying hypnosis and hypnotherapy as a method for smoking cessation have been inconclusive[6]:100;[105][106][107] however, a randomized trial published in 2008 found that hypnosis and nicotine patches "compares favorably" with standard behavioral counseling and nicotine patches in 12-month quit rates.[108]
- Herbs: Many herbs have been studied as a method for smoking cessation, including lobelia and St John's wort.[109][110] The results are inconclusive, but St. Johns Wort shows few adverse events. Lobelia has been used to treat respiratory diseases like asthma and bronchitis, and has been used for smoking cessation because of chemical similarities to tobacco; lobelia is now listed in the FDA's Poisonous Plant Database.[111][112] Lobelia can still be found in many products sold for smoking cessation and should be used with caution.
- Smokeless tobacco: There is little smoking in Sweden, which is reflected in the low cancer rates for Swedish men. Use of snus (a form of steam-cured, rather than heat-cured, smokeless tobacco) is an observed cessation method for Swedish men.[113]
- There are many other measures used in an effort to quit smoking which lack evidence including: a substance put on the cigarette called NicoBloc.[114] Due to the lack of evidence they are typically not recommended.[115]
- Credits: wikipedia.org
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