Tobacco Dependence and Treatment for RNs and LPNs Nursing CE Course

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This course provides an overview of tobacco dependence, its effects on health, and evidence-based management strategies. It offers nurses guidance and resources to help patients with smoking cessation.

After this activity, the nurse should be able to:

• review the scope of tobacco dependence in the US
• discuss the deleterious health effects of tobacco dependence on individuals, close contacts, their communities, and its impact on society
• review the various treatment approaches for tobacco dependence, including counseling, behavioral therapy, pharmacological treatments, and alternative therapies 

The Scope of Tobacco Use 

Despite its devastating health effects, tobacco use remains the leading cause of preventable disease, disability, and death throughout the US (US Department of Health and Human Services [HHS], 2020). According to the National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP, 2021), approximately 34 million US adults smoke cigarettes; most of them smoke daily, and nearly all adult smokers have been smoking since adolescence. Each day, roughly 1,600 young persons under 18 years try their first cigarette, and about 200 become daily cigarette smokers. Cigarette smoking causes more than 480,000 deaths in the US each year, including 41,000 deaths from secondhand smoke (i.e., nonsmokers who breathe in smoke from those around them). For every person in the US who dies due to smoking, at least 30 live with a serious smoking-related illness (NCCDPHP, 2021). Worldwide, there are an estimated 1.3 billion tobacco users. Tobacco kills up to half of its users and is responsible for more than 8 million deaths across the globe each year (World Health Organization [WHO], 2021). On average, smokers die ten years earlier than nonsmokers (Centers for Disease Control and Prevention [CDC], 2021a. 2021c).

The tobacco industry flourished between the 1920s and the 1960s. Tobacco use peaked in the mid-1960s, at which time more than 40% of the US adult population smoked cigarettes (US National Academies Press [NAP], 2007). In 1964, the Surgeon General released a landmark report warning the public of the severe health hazards of smoking. As part of its mission to enhance and protect the health and well-being of the public, the HHS (2020) has led ongoing efforts to prevent and reduce the damaging effects of tobacco use. Nearly six decades later, although these combined efforts have led to a 67% decline in cigarette smoking among US adults, tobacco dependence remains a serious public health problem (HHS, 2020). The CDC’s National Health and Nutrition Examination Survey revealed that progress toward reducing exposure to secondhand smoke among US nonsmokers has stalled since 2011. As described in the report, at least 58 million nonsmokers are exposed to secondhand smoke, and exposure remains very high for specific groups, such as those living in poverty (48%), people living in rental housing (39%), and children aged 3 to 11 years (38%; CDC, 2018). Currently, roughly 14% of the US adult population (15.3% of men and 12.7% of women) smoke cigarettes despite their well-publicized deleterious health consequences. Among adolescents, nearly 7 of 100 middle-school students (6.7%) and approximately 23 of 100 high-school students (23.6%) use tobacco. The US spends more than $300 billion annually on smoking-related illnesses, with more than $225 billion in direct medical care for adults and $156 billion in lost productivity due to premature death and exposure to secondhand smoke. Correspondingly, the tobacco industry spends billions of dollars on cigarette and smokeless tobacco advertising each year (CDC, 2021a, 2021c). 

All forms of tobacco are harmful. According to the WHO (2021), there is no safe level of tobacco exposure. While cigarette smoking is the most common form of tobacco use worldwide, related products include waterpipe tobacco, smokeless tobacco, cigars, pipe tobacco, and electronic nicotine-delivery systems (e-cigarettes, e-cigs, or vape pens). Nurses are well-positioned throughout healthcare settings to educate patients on strategies to improve health outcomes and reduce societal costs by managing this addiction (HHS, 2020). 

The Health Effects of Tobacco Use

The Surgeon General published the Health Consequences of Smoking—50 Years of Progress in 2014. The report elucidated research regarding new findings on the health consequences of nicotine and tobacco products and launched a national campaign to alert the public. As demonstrated in Figure 1, the conditions highlighted in red are new diseases that were causally linked to smoking in the report (HHS, 2014).

Smoking harms nearly every organ in the body. It causes significant disease, disability, and chronic health conditions. Smoking is linked to various forms of cancer, interferes with cancer treatment, delays wound healing following surgery, and increases the risk of cancer recurrence. Cigarette smoking damages the airways and alveoli (small air sacs in the lungs), leading to lung conditions such as chronic obstructive pulmonary disease (COPD), which includes emphysema and chronic bronchitis. According to the NCCDPHP (2021), smoking is responsible for approximately 8 in 10 (80%) of COPD-related deaths and about 90% of lung-cancer-related deaths. Smoking is a significant cause of cardiovascular disease (CVD) as it damages the heart and vessels. The nicotine in cigarettes causes blood vessels to narrow and the heart to beat faster, which increases blood pressure. The chemicals in cigarettes increase triglycerides and reduce high-density lipoprotein (HDL), leading to atherosclerosis (plaque buildup) in the arteries. As a result, the blood in the arteries thickens, increasing the risk of thrombus (blood clot formation), which can impede blood flow to the heart and brain, causing myocardial infarction (heart attack), stroke, and death. In addition, cigarette smoking is responsible for 1 in 4 deaths from heart disease and stroke. Smokers have a 30% to 40% increased risk of developing type 2 diabetes mellitus (T2DM) than nonsmokers. Among males, smoking is a known cause of erectile dysfunction (ED). Smoking also increases the risk of tuberculosis, certain eye diseases, and immune problems, such as rheumatoid arthritis (CDC, 2021c; NCCDPHP, 2021). 

Figure 1 does not depict the detrimental impact of secondhand smoke on the body, such as stroke, respiratory illness, lung cancer, and CVD. Secondhand smoke also triggers more frequent and severe asthma attacks. Persons exposed to secondhand smoke at home or work have a 30% higher risk of CVD and stroke than their non-exposed counterparts (CDC, 2021c; HHS, 2020; NCCDPHP, 2021). Smoking during pregnancy and the postpartum period increases the risk of premature birth, low birth weight, and sudden infant death syndrome (SIDS). Prenatal nicotine exposure has been shown to affect lung development (Dinakar & O’Connor, 2016). Secondhand smoke exposure during pregnancy is associated with low-birth-weight neonates and poor pregnancy outcomes. In addition to SIDS, children exposed to secondhand smoke have increased risks of experiencing middle ear disease, impaired lung function, and other acute and chronic respiratory illnesses (CDC, 2021c; HHS, 2020; NCCDPHP, 2021).

Ingredients in Tobacco and Cigarette Smoke

Nicotine was initially derived from the herbaceous plant Nicotiana tabacum, a native of tropical and subtropical America that is now commercially grown worldwide (Siqueira & the Committee On Substance Use And Prevention, 2017). There are about 600 ingredients in cigarettes, and tobacco smoke produces more than 7,000 different chemicals; nearly 70 are known carcinogens (cancer-causing substances). Some of the chemical constituents of cigarettes are outlined in Table 1 (American Lung Association, 2021; Irish Cancer Society, 2021).

In 2014, the Independent Scientific Committee on Drugs convened an international expert panel to rank 12 nicotine-containing products based on their relative harm using the multi-criteria decision analysis (MCDA) approach. Their findings revealed that cigarettes are by far the most harmful (with a score of 100 out of 100) to individuals and others based on 14 independent criteria. Nicotine replacement (NRT) products such as patches and nasal sprays received low scores of 2, whereas small cigars (score 64), pipes (score 21), cigars (score 16), and water pipes (score 14) carried additional harm. This committee credited the bulk of smoking’s damage to CO, tobacco-specific nitrosamines (TSNAs), and nitric oxide (Nutt et al., 2014). A separate study of toxicant exposure in combustible tobacco products (CTPs) listed the potent toxins found in cigarette smoke to include TSNAs, metals such as lead and cadmium, polycyclic aromatic hydrocarbons (PAHs), and volatile organic compounds (VOCs; Goniewicz et al., 2018). 

Electronic Cigarettes (E-Cigs)

Historically, most warnings against smoking have centered on the dangers of tar and CO found in conventional cigarettes. While the overall rate of cigarette smoking has declined, US youth are increasingly experimenting with alternative tobacco products, especially e-cigs. According to a report released by the US Surgeon General, the use of e-cigs (vaping) increased by 900% among high-school students between 2011 and 2015 (HHS, 2016). E-cigs are sold in nearly 8,000 flavors—including cotton candy, apple pie, and gummy bear—to attract younger users. They have been cited as the most used tobacco product among youth since 2014 (CDC, 2020b; Siqueira & the Committee On Substance Use And Prevention, 2017). While the Independent Scientific Committee on Drugs reported that e-cigs were substantially less harmful than combustible (traditional) cigarettes in their 2014 report, their stance was based on a lack of evidence. Their statement on the reduced harms of e-cigs ignited a media frenzy spawning the increased use of e-cigs, especially among youth (Nutt et al., 2014). Since the publication of this report, additional research has disputed their findings, revealing the devastating health consequences of e-cigs. 

E-cigs consist of a reservoir for liquid and a heating element (atomizer) that creates an aerosol from the liquid. The fluid is composed of a solvent (typically vegetable glycerin or propylene glycol), and in addition to added flavors, has various concentrations of nicotine (Dinakar & O’Connor, 2016). In addition to utilizing different materials and copious heating coils, e-cig devices can currently attain a power output that exceeds the 2014 models by up to 20 times. This higher power increases the harm of e-cigs by generating more aerosol and exposing users to more nicotine and other toxicants. Furthermore, modern-day e-cigs increase bystander exposure (secondhand smoke) to their harmful aerosol components as users exhale more aerosol. Even at room temperature, the liquids in e-cigs can be unstable, producing irritating acetal compounds and carcinogens (Eissenberg et al., 2019). According to a review from National Health Interview Surveys (NHIS), vaping is associated with significant cardiac changes related to chronic CVD. E-cig users have higher risks of heart attack, stroke, and circulatory problems than non-users (Vindhyal et al., 2019).

In 2018, the National Academies of Sciences, Engineering, and Medicine (NASEM) published a report on the public health consequences of e-cigs. They cited the Family Smoking Prevention and Tobacco Control Act of 2009, which states that all products introduced after February 15, 2007, must be shown to have a net positive health impact on both users and the community. Among youth and young adults, the use of e-cigs is now significantly higher than the reported use of CTPs. In summary, NASEM reports that current evidence allows for the following conclusive findings (Stratton et al., 2018):

• E-cig use increases the airborne particulate matter and nicotine in the indoor environment.
• Most e-cigs contain and emit numerous potentially toxic substances, including nicotine; however, exposure depends on the device used, the liquid used, and how the product is operated.
• E-cig devices can explode, causing burns and other projectile injuries.
• Intentional or accidental exposure to e-cig liquid (ingestion, eye contact, skin contact) can result in seizures, anoxic brain injury, vomiting, and lactic acidosis. Drinking or injecting e-cig liquid can be fatal.

Nicotine Addiction

More than two-thirds of smokers report a desire to quit, and thousands attempt to stop every day. In 2018, 55.1% (21.5 million) adult cigarette smokers tried to quit during the past year, and 7.5% (2.9 million) were successful (CDC, 2020a, 2021c). According to the HHS (2020), most individuals who try to quit eventually succeed, as 3 in 5 adults who have ever smoked have quit. Due to its highly addictive nature, nicotine is responsible for many failed cessation attempts, and most users make multiple attempts before they stop permanently. Nicotine dependence occurs when the user’s body has become accustomed to having the drug in its system and requires it. Nicotine dependence has physiological and behavioral mechanisms. Nicotine produces a temporary increase in endorphins within the brain's reward circuits, eliciting a slight, brief period of euphoria. It increases levels of the neurotransmitter dopamine in the brain, reinforcing the behavior of taking the drug. It also temporarily bolsters aspects of cognition, such as improving a person’s attention span. For tobacco users, the long-term brain changes induced by continual nicotine exposure lead to addiction. The National Institute on Drug Abuse (NIDA) defines addiction as compulsive drug-seeking and use, even in the face of adverse health consequences. Dependence involves unpleasant withdrawal symptoms when tobacco is withheld, such as irritability, craving, depression, anxiety, cognitive and attention deficits, sleep disturbances, and increased appetite. Withdrawal symptoms can begin within a few hours after the last cigarette, making it harder to sustain the desire to quit (Prochaska & Benowitz, 2019; NIDA, 2020). 

Benefits of Quitting 

According to the HHS (2020), smoking cessation is beneficial at all ages because it improves overall health, dramatically reduces the risk of developing smoking-related diseases, and improves quality of life. The CDC, HHS, and other anti-smoking organizations have generated various public campaigns and educational programs on the benefits of smoking cessation (CDC, 2020a; HHS, 2020). The health benefits of quitting start nearly immediately and extend for decades. See Table 2 for an overview of the time-sensitive health benefits of smoking cessation (CDC, 2020a; HHS, 2020).

Treatment Options for Tobacco Dependence

While multiple evidence-based treatment options are available for tobacco dependence, the HHS (2020) has shown they are widely underutilized. Fewer than 1 in 3 adults who try to quit smoking have used proven cessation treatments. Since tobacco dependence has behavioral (i.e., the habit of using tobacco) and physiological (i.e., addiction) roots, effective treatment should address both aspects. According to a 2019 systematic review conducted by the US Preventive Services Task Force (USPSTF), there is strong evidence that various pharmacologic and behavioral interventions (individually and in combination) effectively contribute to smoking cessation for adults (Patnode et al., 2019). 

Behavioral Approaches

Many studies have demonstrated that behavioral counseling and medication interventions improve smoking cessation outcomes compared with self-help materials or no treatment. There are several behavioral support resources for patients who want to quit using tobacco. Combined with ongoing monitoring, support, and treatment, referring patients to the Quitline (i.e., 1-800-QUIT-NOW) or another cessation resource can improve their chances of quitting. Quitline is a free and confidential telephone-based support staffed by trained counselors available across the US. Internet-based support systems connect patients to others struggling with tobacco dependence and offer cessation-related links and resources for more information. Federally funded text-messaging programs can help patients looking for on-demand encouragement, positive reinforcement, and real-time support. Over recent years, there has also been an influx of smartphone apps that offer ongoing and easily accessible support (CDC, 2021b). 

According to the American Psychiatric Association (APA, 2020), psychotherapy can be utilized to enhance a patient's capacity to make behavioral changes (e.g., quit smoking). Types of psychotherapy with demonstrated efficacy in treating tobacco use and nicotine dependence include cognitive-behavioral therapy (CBT) and acceptance and commitment therapy (ACT). CBT is a short-term, problem-focused intervention that employs both cognitive and behavioral techniques. It teaches patients to restructure cognitive distortions and self-defeating behaviors and replace them with more accurate thoughts and functional behaviors (David et al., 2018). In CBT, patients learn to reframe negative or self-defeating thoughts, making it easier to cope with cravings and unpleasant emotions associated with quitting, including withdrawal symptoms (GoodTherapy, 2020). 

ACT is an action-oriented, process-based intervention that promotes mindfulness techniques to achieve psychological flexibility and help patients live more authentic lives. Psychological flexibility refers to being present, remaining open-minded, and acting consistently with core beliefs. ACT helps patients learn the consequences of avoiding, denying, and suppressing their inner emotions (Hacker et al., 2016). ACT encourages patients to recognize and accept their urges to smoke, with the understanding that these sensations are temporary and will dwindle over time. ACT principles are employed by various smoking-cessation smartphone apps to help smokers achieve enhanced psychological flexibility through education, practice, and committed action (GoodTherapy, 2020; HHS, 2020). 

The HHS (2020) reviewed the available behavioral interventions for smoking cessation and found sufficient evidence to conclude that behavioral counseling and cessation medications (see next section) are independently effective in increasing smoking cessation but even more effective when combined. Furthermore, the HHS found sufficient evidence supporting Quitline counseling services' clinical utility when provided alone or in combination with medications. In addition, text-messaging services are practical and effective mechanisms for improving success rates, especially if they are interactive or offer personalized text responses. Finally, HHS (2020) also supports the value of internet-based behavioral interventions to enhance smoking cessation, stating that they can be more effective when they contain behavioral change techniques and interactive mechanisms for each user.

Nicotine Replacement Therapy (NRT)

NRT was first introduced in the late 1970s to assist smokers with weaning gradually off nicotine, the most physically addicting component of cigarettes. Nicotine undergoes first-pass metabolism, which limits the effectiveness of orally ingested formulations. Therefore, NRT options available over the counter (OTC) in the US include patches, gum, and lozenges. Nasal sprays and inhalers are also available but require a prescription from a licensed prescriber (American Academy of Family Physicians [AAFP], 2019). NRT has been shown to improve smoking cessation rates by 50%-70%. Combined therapy (e.g., using two or more NRT products, such as a patch and gum) is more effective than monotherapy. The transdermal patch is the slowest and longest-acting option, with serum concentrations peaking in 6-8 hours. The most commonly reported adverse effects include insomnia, abnormal dreams, and pruritus, but these improve quickly once the patch is removed. The gum, lozenge, and inhaler formulations peak in 20-60 minutes. Those who use nicotine gum most commonly report flatulence, indigestion, nausea, hiccups, and a sore throat, mouth, or jaw. Adverse effects related to the inhaler include a dry cough and irritation of the mouth and throat. The nasal spray offers the fastest onset of action, peaking in the central nervous system (CNS) within 5-20 minutes; it most closely mimics the effects of smoking a cigarette. Nurses should counsel patients not to abruptly discontinue NRTs; they should be tapered before stopping (AAFP, 2019; Drugs for Tobacco Dependence, 2016). NRT was shown statistically to improve abstinence rates among smokers compared to placebo in the EAGLES trial. In this trial involving over 8,000 adult smokers, the NRT group showed 23.4% and 15.7% abstinence rates at 12 and 24 weeks, respectively, compared to 12.5% and 9.4% in the placebo group (Anthenelli et al., 2016). In a randomized trial involving 657 adult smokers in New Zealand, nicotine patches resulted in a quit rate of 5.8% in that group and 7.3% when combined with e-cigs. In addition, when NRT was studied in pregnant women, its use resulted in decreased smoking in the second trimester and better child development outcomes at two years (Dinakar & O’Connor, 2016). 

Pharmaceuticals

Bupropion sustained-release (SR; Zyban) and varenicline (Chantix) are FDA-approved prescription medications for smoking cessation. Bupropion SR (Zyban) is an atypical antidepressant that primarily functions as a norepinephrine and dopamine reuptake inhibitor. It was developed to treat depression as it helps improve concentration and reduces hyperactivity but was also found to have nicotinic receptor-blocking activity. It has been shown to double smoking cessation rates in short-term studies versus placebo, with roughly similar efficacy to NRT. Bupropion SR (Zyban) has been demonstrated statistically to improve abstinence rates among smokers compared to placebo in the EAGLES trial with 22.6% and 16.2% abstinence rates at 12 and 24 weeks, respectively, compared to 12.5% and 9.4% in the placebo group (Anthenelli et al., 2016). The most commonly reported adverse effects include insomnia, dry mouth, headaches, nausea, anxiety, agitation, increased motor activity, tremors, and tics. To minimize insomnia, nurses should counsel patients to avoid taking bupropion SR (Zyban) at bedtime (AAFP, 2019). 

Varenicline (Chantix) works by blocking nicotine receptors in the brain. As a partial agonist, it binds selectively to 𝛂2β4 nicotinic acetylcholine receptors, inhibiting dopaminergic activation produced by smoking to decrease cravings and withdrawal symptoms. It is more effective than NRT monotherapy or bupropion SR (Zyban) and roughly as effective as combination NRT (Drugs for Tobacco Dependence, 2016; HHS, 2020). The most common adverse effects include nausea, insomnia, vivid dreams, headaches, constipation, vomiting, flatulence, and xerostomia, with increased adverse effects reported when used in combination with NRT. Nurses should counsel patients to take varenicline (Chantix) with a full glass of water after eating to decrease GI upset. Some observational studies have demonstrated an increase in neuropsychological symptoms or an exacerbation of preexisting psychiatric illness and suicidal behaviors (Drugs for Tobacco Dependence, 2016; Singh & Saadabadi, 2021). However, the FDA-mandated EAGLES trial showed no statistically significant increase in moderate to severe neuropsychological adverse events for patients taking varenicline (Chantix) versus placebo. The study’s findings also revealed a statistically significant improvement in abstinence rates with varenicline (Chantix) at 12 and 24 weeks (33.5% and 21.8%, respectively) compared to all other groups (Anthenelli et al., 2016). 

Although not approved in the US, cytisine has been safely used in eastern Europe and many other countries for smoking cessation since the 1960s. Cytisine is a partial agonist of nicotinic acetylcholine receptor 𝛂4β2 and is primary derived from the Cytisus laburnum plant. Clinical trials have demonstrated promising results, linking cytisine to an increased likelihood of smoking cessation as a practical, low-cost medication option. The most common side effects include GI symptoms such as nausea, vomiting, dyspepsia, upper abdominal pain, and a dry mouth. The rationale for its lack of approval in the US is unclear, but critics blame its generic structure and pharmaceutical market exclusivity as the primary obstacles. Cytisine’s low selling price offers minimal financial incentives for companies to pursue costly regulatory approvals in the US (Karnieg & Wang, 2018; Tutka et al., 2019).  

E-Cigs and Smoking Cessation

As described earlier, e-cigs have many negative health consequences and are not approved by the FDA for smoking cessation. Earlier studies demonstrated a small benefit of e-cigs over NRT and other smoking-cessation options, but as newer evidence has emerged regarding the poor health outcomes with e-cigs, research has shifted away from making direct comparisons. A randomized trial of over 650 smokers intending to quit compared NRT patches, an e-cig (with 16 mg added nicotine), and a placebo e-cig. Their findings demonstrated no statistically significant difference between the groups at six months, with abstinence rates ranging from 4.1% (placebo group) to 7.3% (e-cig with nicotine). A meta-analysis of 38 trials of smokers showed that those who used e-cigs were 28% less likely to quit smoking than those who did not (Drugs of Tobacco Dependence, 2016). 

The Nurses Role in Smoking Cessation

According to the HHS (2020), 4 of every 9 adult cigarette smokers who saw a healthcare professional did not receive smoking cessation advice during the past year. Even brief advice to quit (e.g., typically under 3 minutes) from a healthcare professional improves cessation rates and is highly cost-effective. Nurses should educate patients on the health consequences of tobacco use and the health benefits of quitting. Preventing tobacco use among youth is critical to ending the tobacco epidemic. Nurses can effectively integrate smoking cessation discussions into patient encounters by promoting environments that encourage them to quit and offering interventions to make quitting easier (HHS, 2020). 

References

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