Every year, tobacco-related illnesses take the lives of more than 430,000 Americans. The force behind this grim statistic is the chronic, relapsing brain disease of addiction - in this case, addiction to nicotine. Only research on nicotine addiction can provide effective, science-based solutions to this costly public health problem.
More than two decades of NIDA leadership in addiction research have already provided much scientific information about addiction to nicotine. This research has led to the development of smoking prevention and treatment approaches that are helping to counter nicotine's threat to the public health today. NIDA-supported basic and clinical research promises additional improvements in treatment as scientists continue to unravel the mysteries of addiction to nicotine and other abused drugs.
Most smokers know that cigarette smoking and other forms of tobacco use are harmful. Nearly 35 million of them try to quit every year. Yet, without help, only a very small number actually are able to succeed. Science has shown why this is so. The nicotine in tobacco products is a highly addictive drug, and nicotine addiction is characterized by truly compulsive seeking and use, even in the face of harmful consequences.
Research on nicotine addiction has yielded a variety of pharmacological and behavioral treatments that have helped many people combat their nicotine addiction. For example, NIDA-supported research facilitated the development of nicotine replacement therapies, such as nicotine chewing gum and the transdermal nicotine patch, that enable many people to stop smoking. Yet, both research and extensive clinical experience have taught us that treating addiction with medication alone is not nearly as effective as when we couple the medication with a behavioral treatment. For example, we know that less than 10 percent of the people who try to quit smoking on their own are able to refrain from smoking for a year. Pharmacological treatments such as the patch and gum can double the odds of success. However, a combination of pharmacological treatment and behavioral treatment, such as group therapy or social support networks, can improve a smoker's chance of quitting even more.
NIDA's extensive behavioral research program is striving to increase the behavioral treatment options that clinicians can use with pharmacological treatments. Studies now under way are developing new, individualized behavioral treatments that will better motivate smokers to stop smoking and teach them techniques that will enable them to remain abstinent. Other treatment studies are testing whether currently available behavioral therapies, such as contingency management and relapse prevention, are more effective used alone or in combination to help smokers quit.
Every year, 430,000 deaths from cancer and other diseases are attributable to cigarette smoking Source: Centers for Disease Control and PreventionWhile we have made much progress in developing treatments for nicotine addiction, we can and must do more to help the many smokers who still are unable to quit smoking. I am happy to report that ongoing research by NIDA-supported scientists has been uncovering important new information about the nicotine addictive process and how that process drives smoking behavior. We can use these data to help us develop new treatments.
Two recent studies have confirmed inferences from earlier research that some of nicotine's most important effects on emotions and behavior are exerted through the same brain circuits that are activated by other abused drugs. One study shows that, like other drugs of abuse, nicotine elevates levels of the neurotransmitter dopamine in brain pathways that control reward and pleasure. This change in dopamine levels is thought to be a fundamental characteristic of all addictions. The second study shows that, as with withdrawal from other addictive drugs, withdrawal from chronic nicotine use decreases this brain circuit's sensitivity to pleasurable stimulation. Our increased understanding of these changes shows us why it is so hard for people to stop smoking and helps pave the way to better treatments for nicotine withdrawal symptoms. (For more information on these and other nicotine studies, see "Like Other Drugs of Abuse, Nicotine Disrupts the Brain's Pleasure Circuit.")
NIDA-supported researchers also are making excellent progress in identifying the molecular components of nicotine addiction. One recent study has pinpointed a particular protein in the brains of mice that is essential to the process of nicotine addiction. Mice that lack this protein will not self-administer nicotine. This suggests that the mice do not experience the rewarding effects of nicotine. This major discovery provides us with a very specific brain site to target in developing novel nicotine addiction treatment medications.
Although nicotine addiction lies at the root of tobacco use, another recent study by scientists using sophisticated brain imaging technology suggests that, in addition to nicotine, some unknown compound in cigarette smoke also raises dopa-mine levels in smokers' brains by inhibiting an enzyme that breaks down dopamine. If further research confirms that smoking alters dopamine levels through multiple mechanisms, it would open the door to new approaches to developing effective smoking treatment medications (see "Tobacco Smoke May Contain a Psychoactive Ingredient Other Than Nicotine.").
Ultimately, the best treatment for nicotine addiction is prevention. Here, too, a long history of NIDA-supported research has given us the tools to develop effective drug abuse prevention approaches, including strategies to prevent tobacco use. We have distilled this scientific base for drug abuse prevention in the first-ever research-based guide for preventing drug abuse. The principles in this guide, "Preventing Drug Use Among Children and Adolescents," can be applied by families, schools, and communities to prevent adolescents from beginning to use tobacco and other harmful drugs (see "NIDA Materials to Help Communities Develop Drug Abuse Prevention Programs," NIDA NOTES, November/December 1997).
Never before has the momentum for addressing the public health problem posed by tobacco use been greater. To accelerate this momentum, NIDA, in collaboration with the Robert Wood Johnson Foundation, the National Cancer Institute, and the Centers for Disease Control and Prevention Office on Smoking and Health, is holding a scientific conference on nicotine addiction on July 27-28, 1998, in Bethesda, Maryland. The conference, called "Addicted to Nicotine: A National Research Forum," brings together the leaders in nicotine addiction research to share knowledge, identify gaps in that knowledge, and point us toward promising new areas of research. Ultimately, it is that research that will make possible a future in which no more lives are lost to what is ultimately a preventable, and, if not prevented, treatable disease.