Nicotine and Related Disorders

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Nicotine and Related Disorders

Definition

Nicotine disorders are caused by the main psycho-active ingredient in tobacco. Nicotine is a physically and psychologically addictive drug. It is the most influential dependence-producing drug in the United States and worldwide, and its use is associated with many serious health risks.

Description

Nicotine is the most addictive and psychoactive chemical in tobacco, a plant native to the North America. Early European explorers learned to smoke its leaves from indigenous peoples who had been using tobacco for hundreds of years. They took tobacco back to Europe, where it became immensely popular. Tobacco became a major source of income for the American colonies and later for the United States. Advances in cigarette-making technology caused a boom in cigarette smoking in the early 1900s. Before the early twentieth century, most people who used tobacco used pipes, cigars, or chewing tobacco.

In the 1950s, researchers began to link cigarette smoking to certain respiratory diseases and cancers. In 1964 the Surgeon General of the United States issued the first health report on smoking. Cigarette smoking peaked in the United States in the 1960s, then began to decline as health concerns about tobacco increased. In 1971 cigarette advertising was banned from television, although tobacco products are still advertised in other media today. There are about 91.5 million current and former smokers in the United States, and in a 2004 survey, almost 4 million adolescents had tried smoking in the previous month. Most active smokers are addicted to nicotine.

Pure nicotine is a colorless liquid that turns brown and smells like tobacco when exposed to air. Nicotine can be absorbed through the skin, the lining of the mouth and nose, and the moist tissues lining the lungs. Cigarettes are the most efficient nicotine delivery system. Once tobacco smoke is inhaled, nicotine reaches the brain in less than 15 seconds. Because people who smoke pipes and cigars do not inhale, they absorb nicotine more slowly. Nicotine in chewing tobacco and snuff is absorbed through the mucous membranes lining the mouth and nasal passages. There are also several “hard snuff” and other new tobacco products being produced and marketed as alternative to traditional tobacco products. At least one study of the nicotine content of these products has found that some have lower levels of nicotine than regular tobacco products, but others contain comparable levels.

Causes and symptoms

How nicotine works

Nicotine is the main addictive drug among the 4,000 compounds found in tobacco smoke. Such other substances in smoke as tar and carbon monoxide present documented health hazards, but they are not addictive and do not cause cravings or withdrawal symptoms to the extent that nicotine does. Neuroimaging technology has shown that levels of monoamine oxidase, the enzyme responsible for boosting mood-enhancing molecule levels in the brain, increase in response to smoking, even though nicotine does not affect levels of this enzyme. Thus, some other compound in cigarette smoke must be acting to exert this effect. In addition, a compound in cigarette smoke called acetylaldehyde may contribute to tobacco addiction and may have a stronger effect in adolescents.

Nicotine is both a stimulant and a sedative. It is a psychoactive drug, meaning that it works in the brain, alters brain chemistry, and changes mood. Once tobacco smoke is inhaled, nicotine passes rapidly through the linings of the lungs and into the blood. It quickly circulates to the brain where it stimulates release of dopamine , a neurotransmitter (nerve signaling molecule) in the brain that affects mood. Drugs that elicit an increase in dopamine influence the brain’s “reward” pathway, causing the user to turn again to the drug for another pleasurable, rewarding dopamine response. This release accounts for the pleasurable sensation that most smokers feel almost as soon as they light a cigarette. Nicotine also decreases anger and increases the efficiency of a person’s performance on long, dull tasks.

At the same time nicotine affects the brain, it also stimulates the adrenal glands. The adrenal glands are small, pea-sized organs located above each kidney that really act as two different endocrine organs. The adrenal gland produces several hormones in the medulla, or inner layer, including epinephrine, also called adrenaline . Under normal circumstances, adrenaline is released in response to stress or a perceived threat. It is sometimes called the “fight or flight” hormone, because it prepares the body for action. When adrenaline is released, blood pressure, heart rate, blood flow, and oxygen use increase. Glucose, a simple form of sugar used by the body, floods the body to provide extra energy to muscles. The overall effect of the release of the stress hormones is strain on the cardiovascular (heart and blood vessels) system. This response to stress produces inflammation in the blood vessels that ultimately results in buildup of plaque, which can block the vessels and cause stroke or heart attack.

Most people begin smoking between the ages of 12 and 20. Few people start smoking as adults over 21. Adolescents who smoke tend to begin as casual smokers, out of rebelliousness or a need for social acceptance. Dependence on nicotine develops rapidly, however; one study suggests that 85–90% of adolescents who smoke four or more cigarettes become regular smokers. Nicotine is addictive, so being tobacco-free soon feels uncomfortable for users. In addition, smokers quickly develop tolerance to nicotine. Tolerance is a condition that occurs when the body needs a larger and larger dose of a substance to produce the same effect. For smokers, tolerance to nicotine means more frequent and more rapid smoking. Soon most smokers develop physical withdrawal symptoms when they try to stop smoking. Users of other forms of tobacco experience the same effects; however, the delivery of nicotine is slower and the effects may not be as pronounced.

Nicotine dependence

In addition to the physical dependence caused by the actions of nicotine on the brain, there is a strong psychological component to the dependency of most users of tobacco products, especially cigarette smokers. Most people who start smoking or using smokeless tobacco products do so because of social factors. These include:

the desire to fit in with peers
acceptance by family members who use tobacco
rebelliousness
the association of tobacco products with maturity and sophistication
positive response to tobacco advertising

Such personal factors as mental illness (depression, anxiety, schizophrenia, or alcoholism); the need to reduce stress and anxiety; or a desire to avoid weight gain also influence people to start smoking. Once smoking has become a habit, whether physical addiction occurs or not, psychological factors play a significant role in continuing to smoke. People who want to stop smoking may be discouraged from doing so because:

they live or work with people who smoke and who are not supportive of their quitting
they believe they are incapable of quitting
they perceive no health benefits to quitting
they have tried to quit before and failed
they associate cigarettes with specific pleasurable activities or social situations that they are not willing to give up
they fear gaining weight

Successful smoking cessation programs must treat both the physical and psychological aspects of nicotine addiction.

Nicotine withdrawal

The American Psychiatric Association first recognized nicotine dependence and nicotine withdrawal as serious psychological problems in 1980. Today nicotine is considered an addictive drug, although a common and legalized one.

As is widely recognized, quitting can be difficult. Among people who try, between 75% and 80% will relapse within six months. Because of this rate, research has found that smoking cessation programs that last longer than six months can greatly enhance quit rates, achieving rates as high as 50% at one year. Combining a nicotine-withdrawal product (described below) with a behavioral-modification or support program has produced the greatest success rates.

The combination of physiological and psychological factors make withdrawal from nicotine very difficult. Symptoms of nicotine withdrawal include:

irritability
restlessness
increased anger or frustration
sleep disturbances
inability to concentrate
increased appetite or desire for sweets
depression
anxiety
constant thoughts about smoking
cravings for cigarettes
decreased heart rate
coughing
Withdrawal symptoms are usually more pronounced in smokers than in those who use smokeless tobacco products, and heavy smokers tend to have more symptoms than light smokers when they try to stop smoking. People with depression, schizophrenia, alcoholism, or mood disorders find it especially difficult to quit, as nicotine offers temporary relief for some of the symptoms of these disorders.

Symptoms of nicotine withdrawal begin rapidly and peak within one to three days. Withdrawal symptoms generally last three to four weeks, but a significant number of smokers have withdrawal symptoms lasting longer than one month. Some people have strong cravings for tobacco that last for months, even though the physical addiction to nicotine is gone. These cravings often occur in settings in which the person formerly smoked, such as at a party or while driving, or after a meal. Researchers believe that much of this extended craving is psychological.

Demographics

Although the prevalence of smoking has gradually decreased in the United States and many other industrialized countries since the 1970s, the use of tobacco products is rapidly increasing in developing nations, where approximately 80% of current smokers live. Younger populations may be particularly vulnerable. For example, a CDC survey from 2003 found that almost 42% of teenaged boys in one city in Mali were cigarette smokers. The World Health Organization currently attributes 4.9 million deaths per year globally to tobacco use among the estimated 1.2 billion smokers worldwide, a death total expected to double in two to three decades. Use of tobacco products in developing countries is of particular concern because these countries often lack adequate health care resources to treat smoking-related diseases, let alone support smoking cessation programs.

In the United States, the percentage of men who smoke outnumbers that of women 23% to 18.7%. In developing countries, male smokers outnumber women smokers, but among adolescent populations, girls and boys are becoming more equal in their rates of smoking. In the United States, people who smoke tend to have lower levels of formal education than those who do not. About half of patients diagnosed with psychiatric problems are smokers, while more than three-quarters of those who abuse other substances also smoke.

From 1997 to 2005, smoking among high-school students had declined after increasing dramatically in the 1990s; however, in 2005, there appears to have been a slight uptick in percentage of smokers in this group. Smoking among women with less than a high school education has shown a steady decline since a bump upward in 1995, but there was a slight increase from 2002 to 2004 among women with a high-school education. Smoking rates among white and African American males overall were almost identical in 2004, but African American males in the between the ages of 45 and 65 had the highest rates of any group, at 29% in 2004. Among pregnant women, the highest rates of smoking in 2003 occurred among American Indian or Alaska Native women, at 18%. In an age breakdown, women in the 18- to 19-year age group had the highest rates of smoking during pregnancy, at 17%, while education plays a strong role in whether or not a pregnant woman smokes: rates among women without a high-school diploma were 25.5%, while rates among women with at least a four-year degree were 1.6%.

Recent research suggests that there may be a genetic component to nicotine dependence, just as there is for alcohol dependence. Studies show that girls (but not boys) whose mothers smoked during pregnancy are four times more likely to smoke than those whose mothers were tobacco-free during pregnancy. Other research suggests that the absence of a certain enzyme in the body protects the body against nicotine dependence. In addition, there appears to be a sex-based difference among smokers: women may have a harder time quitting smoking.

Diagnosis

Smokers usually self-diagnose their nicotine dependence and nicotine withdrawal. Such questionnaires as the Fagerstrom Test for Nicotine Dependence (FTND), a short six-item assessment of cigarette use, help to determine the level of tobacco dependence. Physicians and mental health professionals are less concerned with diagnosis, which is usually straightforward, than with determining the physical and psychological factors in each patient that must be addressed for successful smoking cessation.

Treatments

Most people do not decide to stop smoking all of the sudden. Instead, they go through several preparatory stages before taking action. First is the precon-templation stage, in which the smoker does not even consider quitting. Precontemplation is followed by the contemplation stage, in which the smoker thinks about quitting, but takes no action. Contemplation eventually turns to preparation, often when counselors or family members encourage or urge the smoker to quit. Now the smoker starts making plans to quit soon. Finally the smoker arrives at the point of taking action.

Having decided to stop smoking, a person has many choices of programs and approaches. When mental health professionals are involved in smoking cessation efforts, one of their first jobs is to identify the physical and psychological factors that keep the person smoking. This identification helps to direct the smoker to the most appropriate type of program. Assessment examines the frequency of the person’s smoking, his or her social and emotional attachment to cigarettes, commitment to change, available support system, and barriers to change. These conditions vary from person to person, which is why some smoking cessation programs work for one person and not another.

Medications

Before 1984, there were no medications to help smokers quit. In that year, a nicotine chewing gum (Nicorette) was approved by the United States Food and Drug Administration (FDA) as a prescription drug for smoking cessation. In 1996 it became available without prescription. Nicorette was the first of several medications used for nicotine replacement therapy, intended to gradually reduce nicotine dependence to prevent or reduce withdrawal symptoms. This approach, called tapering, is used in withdrawal of other addictive drugs. Studies indicate that people using these replacement therapies do not become addicted to them.

Nicotine gum comes in two strengths, 2 mg and 4 mg. As the gum is chewed, nicotine is released and absorbed through the lining of the mouth. Over a 6-to 12-week period, the amount and strength of gum chewed can be decreased, until the smoker is weaned away from his or her dependence on nicotine. People trying to quit smoking are instructed to use the gum when they feel a craving. Products with caffeine may limit nicotine absorption and should be avoid in a window of time around the gum “dose.” Some people may not like the taste of the gum, and other common side effects include burning mouth and sore jaw. Anyone with heart problems, diabetes, ulcers, or who is pregnant or breastfeeding should consult with a doctor before beginning any nicotine-replacement product.

The nicotine transdermal patches have been available without prescription since 1996. They are marketed under several brand names, including Habitrol, Nicoderm, NicoDerm CQ, Prostep and Nicotrol. All but Nicotrol are 24-hour patches. Nicotrol is a 16-hour patch designed to be removed at night. The patches are worn on the skin between the neck and the waist and provide a steady delivery of nicotine through the skin. Patches like Nicoderm come in varying strengths, and after several weeks, users can move down to a patch that delivers a lower dose. With the Nicotrol patch, a user simply ceases use after six weeks. Some people using the 24-hour patches experience sleep disturbances, and a few develop mild skin irritations, but generally side effects are few. Although fears that using a patch and smoking simultaneously have not been borne out, doctors still recommend not using the patch while smoking.

Two other nicotine delivery devices are available by prescription only. One is a nicotine nasal spray. It has the advantage of delivering nicotine rapidly, just as a cigarette does, although it delivers a much lower dose than a cigarette. Treatment with nasal spray usually lasts four to six weeks. Side effects include cold-like symptoms (runny nose, sneezing, etc.). A nicotine inhaler is also available that delivers nicotine through the tissues of the mouth. A major advantage of the inhaler is that it provides an alternative to having a cigarette in one’s hands while still delivering nicotine. It delivers less nicotine in cold weather (under 50°F). Recommendations for both the spray and the inhaler are that they be used at least hourly at first.

There are two prescription drugs that are not nicotine replacement therapy that have been approved for treatment of nicotine dependence. The first-approved drug was buproprion (Zyban®), an antidepressant that acts to cut down withdrawal symptoms. This drug may be used in combination with a nicotine-replacement therapy and behavioral therapy.

The newer drug is varenicline (Chantix), which was developed to help people stop smoking. This drug acts directly on the proteins in the brain that recognize and bind nicotine. Interfering with their action not only stops the brain from sending the pleasurable message of nicotine but also reduces the feelings of nicotine withdrawal. Some studies indicate that this drug can double a person’s chances of quitting smoking. Side effects of this drug can include headache, nausea, vomiting, sleep problems, gas, and changes in taste sensation.

There is also a combination therapy of atropine and scopolamine that some nicotine cessation programs use. These are two anticholinergic (they block the effects of a class of protein receptors, the acetocho-line receptors) drugs that affect dopamine levels in the brain and are administered in the form of shots, followed by self-administration with pills or patches. Side effects of these drugs include dry mouth, constipation, dizziness, or blurry vision, and people with conditions such as heart problems, high blood pressure, or glaucoma, cannot use these programs. In addition, use of this combination for smoking cessation is “off-label” (not approved by the FDA for this purpose), and there are no published studies on success rates with this approach.

Behavioral treatments

Behavioral treatments are used to help smokers learn to recognize and avoid specific situations that trigger desire for a cigarette. They also help the smoker learn to substitute other activities for smoking. Behavioral treatments are almost always combined with smoker education, and usually involve forming a support network of other smokers who are trying to quit.

Behavioral treatments often take place in support groups either in person or online. They are most effective when combined with nicotine reduction therapy. Other supportive techniques include the use of rewards for achieving certain goals and contracts to clarify and reinforce the goals. Aversive techniques include asking the smoker to inhale the tobacco smoke deeply and repeatedly to the point of nausea, so that smoking is no longer associated with pleasurable sensations. Overall, quit rates are highest when behavior modification is combined with nicotine replacement therapy and tapering. Behavior modification once was conducted in person, but with the advent of a telephonic and virtual world on the Internet, behavioral approaches have been adapted to mail, telephone, and the Web for greater access and flexibility. In 2004, the U.S. Department of Health and Human Services created a toll-free number for people who want to quit: 800-QUIT-NOW (800-784-8669). This number serves as the point of contact for smokers who want information and help.

Alternative treatments

Many alternative therapies have been tried to help smokers withdraw from nicotine. Hypnosis has proved helpful in some cases, but has not been tested in controlled clinical trials . Acupuncture , relaxation techniques, restricted environmental stimulation therapy (REST, a combination of relaxation and hypnosis techniques), special diets , and herbal supplements have all been used to help people stop smoking. Of these alternative techniques, clinical studies of REST showed substantial promise in helping people stop smoking permanently.

Prognosis

Smoking is a major health risk associated with nicotine dependence. About half of all smokers die of a smoking-related illness, often cancer. Most lung cancers are linked to smoking, and smoking is linked to about one-third of all cancer deaths. It kills an estimated 440,000 U.S. citizens each year—more than alcohol, cocaine , heroin, homicide, suicide , car accidents, fire, and AIDS combined. Smoking also causes such other lung problems as chronic bronchitis and emphysema, as well as worsening the symptoms of asthma. Other cancers associated with smoking include cancers of the mouth, esophagus, stomach, kidney, colon, and bladder. Smoking accounts for 20% of cardiovascular deaths. It significantly increases the risk of heart disease, heart attack, stroke, and aneur-ysm. Women who smoke during pregnancy have more miscarriages, premature babies, and low-birth-weight babies than non-smokers. In addition, there is a twofold increased risk that a child born to a mother who smokes will die of Sudden Infant Death Syndrome, thus making smoking an avoidable factor in this tragic occurrence. Secondhand smoke also endangers the health of nonsmokers in the smoker’s family or workplace. Although most of these effects are not caused directly by nicotine, it is dependence on nicotine that keeps people smoking.

Even though it is difficult for smokers to break their chemical and psychological dependence on nicotine, they should remember that most of the negative health effects of smoking are reduced or reversed after

KEY TERMS

Adrenaline —Another name for epinephrine, the hormone released by the adrenal glands in response to stress. It is the principal blood-pressure raising hormone and a bronchial and intestinal smooth muscles relaxant.

Cold turkey —A slang term for stopping the use of nicotine (or any other addictive drug) suddenly and completely.

Dopamine —A chemical in brain tissue that serves to transmit nerve impulses (is a neurotransmitter) and helps to regulate movement and emotions.

Epinephrine —A hormone secreted by the adrenal glands in response to stress.

Plaque —A sticky cholesterol-containing substance that builds up on the walls of blood vessels, reducing or blocking blood flow.

Supportive —An approach to smoking cessation that seeks to encourage the patient or offer emotional support to him or her, as distinct from insight-oriented or exploratory approaches to treatment.

Tolerance —Progressive decrease in the effectiveness of a drug with long-term use.

Withdrawal —Symptoms experienced by a person who has become physically dependent on a drug, experienced when the drug use is discontinued.

quitting. Therefore, it is worth trying to quit smoking at any age, regardless of the length of time a person has had the habit.

Prevention

The best way to avoid nicotine dependence and withdrawal is to avoid the use of tobacco products.

See alsoStress; Substance abuse and related disorders.

Resources

BOOKS

American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 4th ed., Text rev. Washington D.C.: American Psychiatric Association, 2000.

Brigham, Janet. Dying to Quit: Why WeSmoke and How We Stop. Washington D.C.: John Henry Press, 1998.

Galanter, Marc and Herbert D. Kleber, eds. Textbook of Substance Abuse Treatment. 2nd ed. Washington D.C.: American Psychiatric Press, 1999.

O’Brien, Charles P. “Drug Addiction and Drug Abuse.” Goodman & Gilman’s The Pharmacological Basis ofTherapeutics, edited by J. G. Hardman and L. E. Lim-bird. 9th ed. New York and St. Louis, MO: McGraw-Hill, 1996.

Sadock, Benjamin J. and Virginia A. Sadock, eds. Comprehensive Textbook of Psychiatry. 7th ed. Vol. 1. Philadelphia: Lippincott Williams & Wilkins, 2000.

PERIODICALS

Black, Paul H., and Garbutt, Lisa D. “Stress, Inflammation, and Cardiovascular disease.” Journal of Psychosomatic Research 52 (2002): 1–23.

Mathias, Robert. “Daughters of Mothers Who Smoked During Pregnancy Are More Likely to Smoke, Study Says.” NIDA Notes 10.5 (Sept.-Oct. 1995).

National Institute on Drug Abuse. “Nicotine Addiction.” National Institute on Drug Abuse Research Report Series 21 (Feb. 2001).

United States Department of Health and Human Services. “2001 Monitoring the Future Survey Released” HHS News 10 (Dec. 2001).

ORGANIZATIONS

American Cancer Society. National Headquarters, 1599 Clifton Road NE, Atlanta, GA 30329. Telephone: (800) (ACS)-2345. <http://www.cancer.org>

American Lung Association. 1740 Broadway, New York, NY 10019. Telephone: (212) 315-8700. <http://www.lungusa.org>

Cancer Information Service. National Cancer Institute, Building 31, Room 10A19, 9000 Rockville Pike, Bethesda, MD 20892. Telephone: (800) 4-CANCER. <http://www.nci.nih.gov/cancerinfo/index.html>

Nicotine Anonymous. Telephone: (415)750-0328. <http://www.nicotine-anonymous.org>

Smokefree.gov. (Online materials, including information about state-level, telephone-based programs). Telephone: 800-QUIT-NOW (800-784-8669). <http://www.smokefree.gov>

OTHER

American Cancer Society. “Guide for Quitting Smoking.” <http://www.cancer.org/docroot/PED/content/PED_10_13X_Guide_for_Quitting_Smoking.asp>

American Psychiatric Association, 1400 K Street NW, Washington, DC 20005. <http://www.psych.org>

Campaign for Tobacco-Free Kids. “Public Health Groups File Petition Urging FDA to Regulate New ‘Reduced Risk’ Products Being Marketed to Smokers as Healthier Alternatives.” <http://tobaccofreekids.org/Script/DisplayPressRelease.php3?Display=429>

Centers for Disease Control, National Center for Health Statistics.“Smoking:rdquo;<http://www.cdc.gov/nchs/fastats/smoking.htm>.

Centers for Disease Control, Smoking and Health Resource Library. “New citations: links to the latest scientific publications on tobacco and smoking.” <http://apps.nccd.cdc.gov/shrl/NewCitationsSearch.aspx>

“Common myths about quitting smoking.” <http://www.psych.org/psych_pract/treatg/patientfam_guide/Nicotine.pdf>

Department of Health and Human Services. “Tobacco: Global Effects of Tobacco Use.” <http://www.globalhealth.gov/tobacco.shtml>

“The Fagerstrom Test for Nicotine Dependence.” Available online: <http://ww2.heartandstroke.ca/DownloadDocs/PDF/Fagerstrom_Test.pdf

National Library of Medicine. “Smoking cessation.” <http://www.nlm.nih.gov/medlineplus/smokingcessation.html>

Tish Davidson, A.M.

Emily Jane Willingham, PhD

The Gale Encyclopedia of Mental Health