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Nora D. Volkow, M.D.
Director,
National Institute on Drug Abuse
National Institutes of Health
Department of Health and Human Services
April 1, 2004
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Statement for the Record
Mr. Chairman and Members of the Committee:
I am pleased to present the President's budget request for the National Institute on Drug Abuse. The fiscal year (FY) 2005 budget includes $1.019 billion, an increase of $28.273 million over FY 2004 conference level of $990.787 million comparable for transfers proposed in the President's request.
NIDA: 30 Years of Discovery
As the National Institute on Drug Abuse (NIDA) prepares to celebrate its 30th anniversary this year, I am honored to have this opportunity to tell you about some of our remarkable scientific accomplishments and how these advances are setting the course for a better future. A tomorrow that will bring us even better prevention interventions to deter the initial use of drugs by those at risk before they become one of the more than 180 million people around the world who currently abuse illegal drugs. A future that will also bring us better treatment interventions to help those who have already become addicted, and who may suffer from some of the myriad consequences of drug abuse including HIV/AIDS and comorbid mental illnesses. Research supported by NIDA, the world's largest supporter of research on the health aspects of drug abuse and addiction, may even bring us innovative and improved ways to deal with other major health epidemics impacting our society, such as chronic pain and obesity.
Addiction and Obesity: Common Neurobiological Mechanisms
Obesity and addiction are serious National health problems that may have much in common. Both addiction and some forms of obesity represent problems resulting from excessive behaviors and lack of impulse control. Knowledge derived from addiction research shows that the brain circuits involved in compulsive eating and impulse regulation are part of the same brain systems involved in addiction, with the neurotransmitter dopamine playing a prominent role. (See Figure 1.) A better understanding of the role of the dopamine and other systems in the motivation for and salience of food may lead us to the development of better medications and behavioral interventions for obesity, as well as addiction. In addition, medications being developed for obesity may also help to reduce drug use. Because of the commonalities between these disorders, we are able to share knowledge of brain and behavior and combine efforts across institutes to forge new insights and approaches that may result in improved health for all. NIDA is pleased to be a key participant in a trans-NIH initiative that is looking at all aspects of this chronic health problem, from its neurobiological underpinnings to helping people establish healthy behaviors.
The Integration of Brain, Behavior and Health
Understanding the connections between brain, behavior, and health will be critical to improving the health of ALL Americans. Science is at a point where all the elements of the human brain (genes, proteins, circuits) and its development can now be mapped out. We did it with the Human Genome and I am confident we can do it with the brain. We are already beginning to unravel how various genes, proteins, brain circuits and pathways interact with each other and the environment to affect all aspects of human behavior. This overarching approach is necessary if we are to make progress in improving the quality of life for individuals who suffer from complex disorders, such as drug addiction, which can start at a young age and continue across the lifespan. Now that advances in medical sciences have increased the lifespan of humans, a major challenge becomes to improve the quality of life of individuals, which hinges on our ability to understand the neurobiological underpinnings of human behavior and the impact and malleability the environment can have on it. This pertains not only to problems such as addiction, but other health problems such as obesity, adherence to medical regimens and with establishing and maintaining healthy life styles.
Adolescence, the Developing Brain, and Prevention
Collaborating with other Institutes to map out structural and functional aspects of the brain and how it changes throughout development will help us better understand human behavior, and how we can modify it to improve and extend human life. In particular, understanding the developing adolescent brain will be useful in drug abuse prevention efforts. Research indicates that exposure to drugs of abuse in adolescence, when many changes are occurring in the brain, may be a period of significantly increased vulnerability to drugs' effects. Fortunately, advances in science and NIH-funded studies have now brought us to a point where our researchers can use new animal models, new brain imaging technology and other neurobehavioral assessment tools to probe the development of brain and behavior interactions. These new directions in adolescent research will help to inform us on important aspects of cognition, decision-making, emotional regulation, and risk perception during adolescence, and will help us determine how these play a role in the use and consequences of illicit drugs. Armed with new knowledge about how adolescents make decisions, NIDA will be poised to design interventions that can reduce drug experimentation and addiction. We are making progress in this regard through our National Prevention Research Initiative and through our science education activities like "NIDA Goes Back to School Campaign" where science-based materials were disseminated to teachers and students all across America.
Excellent News: Drug Use Declines
Some of the best news to a NIDA Director came in December 2003 when we released the latest data on teen drug use trends. NIDA's long-standing Monitoring the Future Survey showed an approximately 11% decline in illicit drug use over the last 2 years by students in the eighth, tenth, and twelfth grades combined. (See Figure 2.) The use of MDMA or Ecstasy decreased by almost fifty percent for the three grades combined in that same time period Also encouraging was the fact that tobacco use among this population was the lowest in the 28 year history of the survey.
News for Concern: Prescription Drug Abuse Continues
There was also some disturbing news last year about youth drug use, showing very high rates of abuse of prescription pain killers (e.g., Vicodin® and OxyContin®). Remarkably, one in ten twelfth graders reported abusing Vicodin® last year, making it the second most widely abused illicit substance after marijuana in this population. Hospitals are also seeing more patients coming to emergency rooms for prescription drug abuse. According to data from SAMHSA, between 1994 and 2001 the number of emergency room mentions for hydrocodone and oxycodone increased 131% and 352% respectively. When used as prescribed, medications like Vicodin® can be very effective, but when used improperly they can have very serious adverse health consequences including death from overdose. More research is needed to prevent, educate, and treat prescription drug abuse. Developing new medications that have no abuse or diversion potential is a high priority for NIDA.
Researchers are making progress in this area. Just last year, researchers developed a compound to selectively affect a cannabinoid receptor that is involved in regulating pain. Unlike many other receptors, this one is not found in the brain. When the compound (AM1241) was given to animals, they were less sensitive to several forms of painful stimulation. Not only does this research open up a new arena for pain medication development, but it also sets the stage for developing new medications that are less likely to be abused. Also, NIDA's investment in the development of buprenorphine/naloxone for treating opioid addiction, for example, provides an alternative medication for pain that has less diversion potential than that of other opiate analgesics, and exemplifies how science can help alleviate our Nation's problems.
Research on the Consequences of Marijuana, and the Development of New Medications
Research continues to shed new light on the deleterious consequences of marijuana, the most abused illegal drug in the United States. Early exposure to marijuana, for example, has been found to increase the likelihood of a lifetime of subsequent drug problems. A recent study, published in the Journal of the American Medical Association of over 300 fraternal and identical twin pairs, who differed on whether or not they used marijuana before the age of 17, found that those who had used marijuana early had elevated rates of other drug use and drug problems later on, compared to their twin who did not use marijuana before age 17. This study re-emphasizes the importance of primary prevention by showing us that early drug initiation is associated with increased risk of later drug problems, and it provides more evidence for why preventing marijuana experimentation during adolescence could have a big impact in preventing addiction.
We are also finding that a lifetime of heavy cannabis use can result in an overall dissatisfaction with oneself and with life for most users. Last year, researchers published data on the impact of long-term cannabis use on life achievement such as educational attainment and income. Significantly fewer of the heavy cannabis users completed college and more had household incomes of less than $30,000 compared to individuals who used marijuana minimally.
It is clear, more research is needed to curtail use of this drug. Although the number of marijuana treatment admissions has increased from 92,414 in 1992 to 255,394 in 2001, there are relatively few treatments that have been shown to be effective specifically for marijuana addiction. NIDA is encouraging researchers, as well as the pharmaceutical industry, to become more active in finding new medications for marijuana and for other drugs of abuse. With the fairly recent discovery of an endogenous cannabinoid system with specific receptors and endogenous ligands, the likelihood of finding new targets for medications development is increased. One form of a cannabinoid receptor antagonist (CB1-receptor) has already been developed by several pharmaceutical companies and is undergoing clinical investigation for the treatment of alcoholism and nicotine addition, as well as obesity. Moreover, preliminary data in humans has shown that it can block the effects of marijuana.
Accelerating Research Discoveries Bench to Bedside: Bedside to Community NIH Roadmap and Other Initiatives
For science to be useful in preventing and treating addiction this knowledge has to reach the communities. This is an area where NIDA continues to excel. Over the past few years, NIDA has established and strengthened strong collaborative relationships with a number of government agencies, including the Substance Abuse and Mental Health Services Administration (SAMHSA) to build national infrastructures that can facilitate the flow of research into community practice. NIDA's National Drug Abuse Treatment Clinical Trials Network (CTN), which now serves 27 states plus the District of Columbia and Puerto Rico, and the more newly established National Criminal Justice Drug Abuse Treatment Study (CJ-DATS) exemplify NIDA's commitment to bringing science out of the laboratory and to the community. These initiatives parallel and complement those proposed as part of the NIH Roadmap, including the promotion of interdisciplinary research and the development of improved infrastructures for clinical research, which aim to accelerate the advancement of research discoveries from the bench to the bedside and to the community.
Getting the Medical Community More Involved in Screening and Addressing HIV/AIDS and Other Drug Abuse Consequences
Because drug abuse begins in youth and most pediatricians and family physicians typically do not ask questions about drug use, NIDA has launched a Primary Care Outreach Initiative to educate pediatricians and other primary care physicians about the importance of early detection and treatment. The medical community is also being reminded of the need to recognize substance abuse and addiction as disorders that will affect the course of other diseases, including mental illness, cancer, cardiovascular and pulmonary diseases, trauma and infectious diseases. Injection drug use has directly and indirectly accounted for more than one-third (36%) of AIDS cases in the United States. Data show that drug abuse treatment can reduce activities related to drug use that increase the risk of getting or transmitting HIV. Also the fact that the health and social consequences of drug abuse, including HIV/AIDS, disproportionately affect racial and ethnic minority populations; for example almost half of HIV/AIDS cases occur in African Americans even though they constitute only 11% of the population according to the latest Census data, which highlights the urgency to conduct research that can benefit all populations. (See Figure 3.)
Using our established networks (CTN and CJ-DATS), NIDA is strengthening its commitment to attend to associated health problems like HIV/AIDS, hepatitis and co-morbidity that often accompany substance use. The CTN, for example has a number of treatment protocols underway that address HIV/AIDS and hepatitis. Also, because data suggest that the prevalence of HIV and other infectious diseases is high among drug users in the criminal justice system, with HIV seropositivity rates estimated to be 8-10 times higher than in the general population, NIDA is encouraging more research to prevent and treat the spread of HIV/AIDS and other diseases among individuals in the criminal justice system with substance abuse related problems.
Conclusion
Our Nation's investment in drug abuse research is showing reductions in drug abuse rates and its deleterious consequences at the individual, family, and community level. A continued commitment to medical research, and to working with other agencies and sectors, will lead to new advances, technologies and innovations that will result in a healthier population.
[Testimony Index]
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