presented by Nora D. Volkow, M.D. Director, National Institute on Drug Abuse National Institutes of Health Department of Health and Human Services
Testimony Before the House Subcommittee on Labor-HHS-Education Appropriations
Drug abuse and addiction are a major burden to society, with economic costs alone estimated to exceed $600 billion annually in the United States (ONDCP 2004; Rehm et al. 2009; CDC 2007). This includes health and crime-related costs, and losses in productivity. As staggering as these numbers are, they provide a limited perspective of the devastating consequences of this disease for individuals, families, communities, and society as a whole. Fortunately, dramatic changes in our scientific understanding of how drugs affect the brain and produce their myriad health consequences, including addiction, herald a future of innovative, science-based, and more effective approaches to prevention and treatment interventions.
Future successes will build on the demonstrable progress already emanating from our sustained efforts, as dramatic declines have occurred in the use of both licit and illicit drugs among our Nation's youth since the peak years of the mid- to late-1990s. NIDA's 2009 Monitoring the Future Survey of 8th, 10th, and 12th graders shows, for example, that cigarette smoking is at its lowest point in the 34-year history of the survey. However, 2009 survey data also indicate that this progress is stalling, evincing the need for continued prevention efforts. Prevalence rates for marijuana use, for example, have remained steady over the last 5 years. Also, the nonmedical use of prescription drugs—particularly pain relievers (e.g., Vicodin, OxyContin) and ADHD stimulant medications (e.g., Adderall)—remain areas of concern. Nearly 1 in 10 high school seniors report past-year nonmedical use of Vicodin.
Therefore, NIDA continues to enhance our knowledge base about what works best when it comes to prevention approaches and how to implement them. In that regard, research has clearly demonstrated that universal, broad-based prevention approaches involving the individual, their families, schools, and communities can reduce a diverse set of risky behaviors, including drug abuse.
Ensuring the Successful Translation of Discovery
Multiple lines of evidence demonstrate that addiction is a substantially heritable complex disease whose underlying genetic architecture is studded with modest contributions from hundreds, perhaps thousands of individual genes. Thus, we stand to dramatically enhance our ability to detect significant linkages between specific genetic variations and individual vulnerabilities to addiction and its medical consequences (e.g., tobacco addiction, lung cancer) by harnessing the full potential of new instruments with "deep-sequencing" capability. This new technology allows researchers to efficiently drill down on a genomic region of interest and detect variations at the DNA sequence level that, because of their extremely low frequencies, have been beyond our reach until now. Taking full advantage of such constantly evolving genetic tools can potentially revolutionize our approach to health promotion. Discoveries made in this emergent genomic era are already entering the medications R&D pipeline, exposing new targets against which we can design and test the next generation of pharmacotherapeutics.
The translational success of these efforts hinges on our ability to similarly increase the granularity, accessibility, and cross-connectivity of emerging datasets focused on other critical domains, including environmental factors, pre/perinatal clinical histories, and brain structure and function. The recent creation of a map of functional connectivity among different regions of the resting brain, based on 1,400 healthy volunteers from around the globe, exemplifies the research and clinical potential of novel datasets. This particular map, for example, is poised to establish critical benchmarks, against which researchers will be able to compare patients with brain disorders or identify those at greater risk for addiction and other psychiatric disorders.
Another critical example relates to our ongoing efforts to dissect the multilevel mechanisms that affect individual vulnerability to addiction and related or comorbid disorders. A recently launched NIDA initiative seeks to identify and catalogue key environmental risk variables and their mechanisms of action, including chemical DNA modifications that can turn genes on and off in response to specific environmental exposures (e.g., drug abuse, chronic stress, physical abuse)—known as epigenetic changes.
NIDA recognizes that the eventual linkage among all such maps (genomics, imaging, clinical history, etc.) is more than an academic exercise: the unprecedented level of resolution and multilevel integration that can be achieved by these maturing and interconnected datasets will help us uncover important risk and resiliency mechanisms as well as new molecules and circuits that could be targeted by novel pharmaco/behavioral therapeutics.
Despite nearly unbridled scientific enthusiasm, we continue to confront lingering challenges that are distinct from what occurs with other diseases. Obstacles include, for example, the minimal involvement of the pharmaceutical industry in developing medications for addiction, likely because of real or perceived financial disincentives and stigma. Even so, NIDA continues efforts to bring new medications forward by identifying promising compounds and supporting their development. An important initiative in this context is the development of immunotherapies (e.g., vaccines) for the treatment of nicotine, cocaine, and methamphetamine addictions. The vaccines stimulate the body to produce antibodies that bind a drug while it is still in the bloodstream, thereby reducing its entry into the brain and blocking its pharmacological/behavioral effects. This strategy taps into a well-established model of harnessing the healing powers of our own bodies, a first, for addiction medicine.
To further invigorate the pursuit of addiction medications, NIDA has launched a new Translational Avant-Garde Award to provide the best and brightest researchers a unique opportunity to realize the therapeutic potential of their scientific discoveries. By promoting research projects that are ready for translation, we hope to accelerate the development of new medications, a critical mission as we still have no medications available for stimulant, cannabis, inhalants, or polysubstance abuse, a gap that NIDA is attempting to fill.
Leveraging Science to Reform Addiction Strategies
NIDA is committed to leveraging the best science in pursuit of meaningful health care reform that places access to effective and affordable treatments as top priorities. A critical element of such reform is eliciting the involvement of health care providers in recognizing addiction as a disease that not only produces its own deleterious health effects but also affects many other ailments. Investing physicians in the early detection of potential substance use problems in their patients, and referring them as necessary, can help prevent escalation to abuse and addiction and greatly improve our ability to close the treatment gap. To that end, NIDA has recently deployed NIDAMED, a physician outreach program that includes user friendly online tools designed to help primary-care physicians be the frontline of defense by screening their patients for problematic tobacco, alcohol, and other drug use. This initiative could signal the start of a much needed transformation of drug abuse and addiction as a key factor in the public health equation.
A second critical piece of needed transformation will be to improve understanding of how to deliver the most effective drug abuse interventions to those who need them, and expunge the untenable health disparities that often stem from prejudice and stigma. NIDA strives to serve the needs of our most vulnerable and underserved populations whom drug abuse hits especially hard—including children and adolescents, minorities, prisoners or others involved in the criminal justice system, and people with HIV—testing targeted interventions in real-world settings through NIDA's National Drug Abuse Treatment Clinical Trials Network and Criminal Justice-Drug Abuse Treatment Studies.
NIDA has several initiatives aimed at translating research into transformative clinical outcomes to reduce the burden of drug addiction. These include new strategies such as "Seek, Test, and Treat" (and "retain") to expand HAART coverage in criminal justice and other populations through aggressive outreach, early entry into HIV treatment, and follow-up in the community. This innovative approach is based on research showing that seeking out people who may be at high risk of HIV, testing them, and starting them on treatment immediately after detection can improve outcomes, decrease viral load/infectivity, and thus prevent HIV spread.
Also relevant in this context are NIDA's international HIV prevention and treatment efforts, which will continue to build on past successes, including the development and increasing rates of adoption of buprenorphine for sustaining heroin abstinence and preventing the spread of infectious diseases. Such drug treatment programs have been embraced by countries where HIV is rampant, enabling tens of thousands of opiate-dependent patients to receive medical treatment. These success stories should encourage other countries averse to the use of opioid agonist maintenance treatments (e.g., Russia) to establish their own drug treatment programs.
Reinvigorating and Empowering Biomedical Research
Naturally, rapid scientific advances and increasing momentum for achieving transformative public health reform have led to a greater demand for cross-fertilization between previously disparate fields. One of several efforts made by NIDA to meet this challenge was the establishment of its Avant-Garde Award Program for HIV/AIDS Research, designed to attract scientists with differing perspectives to re-energize the pursuit of novel approaches to HIV prevention and treatment among drug abusers.
Cross-fertilization, however, should start at the beginning of the training spectrum. Thus NIDA is committed to support not only the development of new technologies and information platforms, but also the kinds of creative training paradigms needed to harness the vigor of transdisciplinary research. NIDA has partnered with other NIH Institutes, under the umbrella initiative known as NIH Blueprint, to offer multidisciplinary training opportunities that will foster cross-pollination of innovative brain research potentially affecting multiple neurological/psychiatric disorders.
In sum, NIDA pledges to maintain its leadership role in bringing transformative science to bear on the problem of drug abuse and addiction. This commitment stems from an unwavering belief that the health of the Nation depends on our continued recognition and support of promising biomedical research, and that the rapidly evolving science of addiction offers unprecedented opportunities to achieve enduring public health improvements in this country and around the world. Thank you for this opportunity, and I will be pleased to answer any questions you may have.