Are there gender differences in tobacco smoking?
Several avenues of research now indicate that men and women differ in their smoking behavior. For instance, women smoke fewer cigarettes per day, tend to use cigarettes with lower nicotine content, and do not inhale as deeply as men. However, it is unclear whether this is due to differences in sensitivity to nicotine or other factors that affect women differently, such as social factors or the sensory aspects of smoking.
The number of smokers in the United States declined in the 1970s and 1980s, remained relatively stable throughout the 1990s, and declined further through the early 2000s. Because this decline in smoking was greater among men than women, the prevalence of smoking is only slightly higher for men today than it is for women30. Several factors appear to be contributing to this narrowing gender gap, including increased initiation of smoking among female teens and women being less likely than men to quit31.
Large-scale smoking cessation trials show that women are less likely to initiate quitting and may be more likely to relapse if they do quit30. In cessation programs using nicotine replacement methods, such as the patch or gum, the nicotine does not seem to reduce craving as effectively for women as for men31. Other factors that may contribute to women’s difficulty with quitting are that withdrawal may be more intense for women or that women are more concerned about weight gain.
Although postcessation weight gain is typically modest (about 5–10 pounds), concerns about this may be an obstacle to treatment success. In fact, NIDA research has found that when women’s weight concerns were addressed during cognitive-behavioral therapy, they were more successful at quitting than women who were in a program designed only to attenuate postcessation weight gain32. Other NIDA researchers have found that medications used for smoking cessation, such as bupropion and naltrexone, can also attenuate postcessation weight gain and could become an additional strategy for enhancing treatment success33,34.
It is important for treatment professionals to be aware that standard regimens may have to be adjusted to compensate for gender differences in nicotine sensitivity and in other related factors that contribute to continued smoking.
Smoking and adolescence
There are nearly 4 million American adolescents who have used a tobacco product in the past month1. Nearly 90 percent of smokers start smoking by age 18, and of smokers under 18 years of age, more than 6 million will die prematurely from a smoking-related disease35.
Tobacco use in teens is not only the result of psychosocial influences, such as peer pressure; recent research suggests that there may be biological reasons for this period of increased vulnerability. Indeed, even intermittent smoking can result in the development of tobacco addiction in some teens. Animal models of teen smoking provide additional evidence of an increased vulnerability. Adolescent rats are more susceptible to the reinforcing effects of nicotine than adult rats, and take more nicotine when it is available than do adult animals36.
Adolescents may also be more sensitive to the reinforcing effects of nicotine in combination with other chemicals found in cigarettes, thus increasing susceptibility to tobacco addiction. As mentioned above, acetaldehyde increases nicotine’s addictive properties in adolescent, but not adult, animals. That is, adolescent animals performing a task to receive nicotine showed greater response rates to nicotine when combined with acetaldehyde14. NIDA continues to actively support research aimed at increasing our understanding of why and how adolescents become addicted, and to develop prevention, intervention, and treatment strategies to meet the specific needs of teens.
Are there effective treatments for tobacco addiction?
 Yes, extensive research has shown that treatments for tobacco addiction do work. Although some smokers can quit without help, many individuals need assistance in quitting. This is particularly important because smoking cessation can have immediate health benefits. For example, within 24 hours of quitting, blood pressure and chances of heart attack decrease. Long-term benefits of smoking cessation include decreased risk of stroke, lung and other cancers, and coronary heart disease. A 35-year-old man who quits smoking will, on average, increase his life expectancy by 5.1 years37.
Nicotine Replacement Treatments
Nicotine replacement therapies (NRTs), such as nicotine gum and the transdermal nicotine patch, were the first pharmacological treatments approved by the Food and Drug Administration (FDA) for use in smoking cessation therapy. NRTs are used (in conjunction with behavioral support) to relieve withdrawal symptoms—they produce less severe physiological alterations than tobacco-based systems and generally provide users with lower overall nicotine levels than they receive with tobacco12. An added benefit is that these forms of nicotine have little abuse potential since they do not produce the pleasurable effects of tobacco products—nor do they contain the carcinogens and gases associated with tobacco smoke. Behavioral treatments, even beyond what is recommended on packaging labels, have been shown to enhance the effectiveness of NRTs and improve long-term outcomes.
The FDA’s approval of nicotine gum in 1984 marked the availability (by prescription) of the first NRT on the U.S. market. In 1996, the FDA approved Nicorette gum for over-the-counter (OTC) sales. Whereas nicotine gum provides some smokers with the desired control over dose and the ability to relieve cravings, others are unable to tolerate the taste and chewing demands. In 1991 and 1992, the FDA approved four transdermal nicotine patches, two of which became OTC products in 1996. In 1996 a nicotine nasal spray, and in 1998 a nicotine inhaler, also became available by prescription, thus meeting the needs of many additional tobacco users. All the NRT products—gum, patch, spray, and inhaler—appear to be equally effective.
Additional Medications
Although the major focus of pharmacological treatments for tobacco addiction has been nicotine replacement, other treatments are also being studied. For example, the antidepressant bupropion was approved by the FDA in 1997 to help people quit smoking, and is marketed as Zyban. Varenicline tartrate (Chantix) is a new medication that recently received FDA approval for smoking cessation. This medication, which acts at the sites in the brain affected by nicotine, may help people quit by easing withdrawal symptoms and blocking the effects of nicotine if people resume smoking.
Several other nonnicotine medications are being investigated for the treatment of tobacco addiction, including other antidepressants and an antihypertensive medication, among others. Scientists are also investigating the potential of a vaccine that targets nicotine for use in relapse prevention. The nicotine vaccine is designed to stimulate the production of antibodies that would block access of nicotine to the brain and prevent nicotine’s reinforcing effects.
Behavioral Treatments
Behavioral interventions play an integral role in smoking cessation treatment, either in conjunction with medication or alone. They employ a variety of methods to assist smokers in quitting, ranging from self-help materials to individual cognitive-behavioral therapy. These interventions teach individuals to recognize high-risk smoking situations, develop alternative coping strategies, manage stress, improve problemsolving skills, as well as increase social support. Research has also shown that the more therapy is tailored to a person’s situation, the greater the chances are for success.
Traditionally, behavioral approaches were developed and delivered through formal settings, such as smoking-cessation clinics and community and public health settings. Over the past decade, however, researchers have been adapting these approaches for mail, telephone, and Internet formats, which can be more acceptable and accessible to smokers who are trying to quit. In 2004, the U.S. Department of Health and Human Services (HHS) established a national toll-free number, 800–QUIT–NOW (800–784–8669), to serve as a single access point for smokers seeking information and assistance in quitting. Callers to the number are routed to their state’s smoking cessation quitline or, in states that have not established quitlines, to one maintained by the National Cancer Institute. In addition, a new HHS Web site (www.smokefree.gov) offers online advice and downloadable information to make cessation easier.
Quitting smoking can be difficult. While people can be helped during the time an intervention is delivered, most intervention programs are short-term (1–3 months). Within 6 months, 75–80 percent of people who try to quit smoking relapse11. Research has now shown that extending treatment beyond the typical duration of a smoking cessation program can produce quit rates as high as 50 percent at 1 year38.
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