Challenging assumptions about drugs

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1 Challenging assumptions about drugs Carl L. Hart, Ph.D. Department of Psychology, Columbia University, Division on Substance Abuse, New York State Psychiatric Institute, Department of Psychiatry, College of Physicians & Surgeons of Columbia University, and Institute for Research in African-American Studies, Columbia University

3 Methamphetamine vilified Three assumptions made about the drug Development of superhuman strength unique pharmacological profile cognitive impairments

4 [Cocaine] produces several other conditions that make the fiend a peculiarly dangerous criminal. One of these conditions is a temporary immunity to shock a resistance to the knock down, effects of fatal wounds. Bullets fired into vital parts that would drop a sane man in his tracks, fail to check the fiend. Most of the negroes are poor, illiterate and shiftless.... Once the negro has formed the habit he is irreclaimable. The only method to keep him away from taking the drug is by imprisoning him. And this is merely palliative treatment, for he returns inevitably to the drug habit when released.

5 Perceived risks precipitated legislation Anti-drug Abuse Acts of 1986 & 1988 D r ug 5 - years no p ar o le 10 - years no p ar o le Cr ac k 5 g r am s 50 g r am s Po w de r 500 g r am s 5 k il o s 100-to-1 Ratio

6 Racial discrimination justified by perceived risks led to More than 80% of individuals sentenced for crack cocaine were black % of Federal Cocaine Offenders Black Hispanic White Powder Crack Powder 2000 Crack Powder 2006 Crack Cocaine U.S Sentencing Commission, Cocaine and Federal Sentencing Policy, May 2007

7 Powder Cocaine Crack Cocaine

8 Compromised Cognitive Performance Performance disrupted during night shift work Question: Effects of methamphetamine? DAT: Hit Latency 300 RA: Total Errors 350 RIT: False Alarms Sum Shift Condition Day Night Day within Condition Hart et al. 2003, Psychopharmacology 169, 42-51

10 Methamphetamine offsets disruptions Low oral doses of methamphetamine attenuated night shift-related disruptions in infrequent users Question: effects of larger doses on uncompromised performance? DAT: Hit Latency RA: Total Errors RIT: False Alarms * 300 * 350 * * * 9000 * Sum MA Dose 0 mg 5 mg 10 mg Day within Condition Hart et al. 2003, Psychopharmacology 169, 42-51

11 Caveat: pharmacological factors Relevance of dose Route of administration

12 Methamphetamine vilified Three assumptions made about the drug Development of superhuman strength unique pharmacological profile cognitive impairments

14 160 Systolic Pressure 100 "High" 8 Drug vs. $5 mmhg Rating (max = 100) Number of Doses Chosen (max = 10) AP 12 MA 50 AP 50 MA AP 12 MA 50 AP 50 MA AP 12 MA 50 AP 50 MA Dose Condition (mg/70 kg)

15 The notion that methamphetamine has a unique pharmacological profile is not supported by evidence

16 Methamphetamine vilified Three assumptions made about the drug Development of superhuman strength unique pharmacological profile cognitive impairments

17 Initial Question What do we know about the effects of methamphetamine on the brain and cognition of laboratory animals?

18 Data collected in laboratory animals Methamphetamine produces: neurotoxic effects to monoamine-containing neurons disruptive effects on cognitive functioning in multiple domains (e.g., memory, sequential learning)

19 Data collected in laboratory animals Methamphetamine produces: neurotoxic effects to monoamine-containing neurons disruptive effects on cognitive functioning in multiple domains (e.g., memory, sequential learning) Caveat: deleterious neurobiological and cognitive changes are prevented with prior exposure to several days of escalating doses» also importance of self-administration underscores the importance of using ecologically relevant models

20 drug-taking behavior is abolished 10 Drug vs. Nothing Drug vs. $5 Drug vs. $20 Choice (max = 10) Methamphetamine Dose (mg)

21 important question Question What are the effects of relatively larger doses on uncompromised performance in humans?

22 Summary of performance improvements Domain Investigators Learning/memory Hart et al. 2002; Kirkpatrick et al Reaction time Hart et al. 2002, 2008; Kirkpatrick et al Sustained attention/vigilance Hart et al. 2008; Johnson et al. 2000, 2005, 2007; Kirkpatrick et al. 2012; Silber et al Visuospatial perception Hart et al. 2002, 2008; Johnson et al. 2005, 2007; Kirkpatrick et al. 2012; Rush et al. 2011; Silber et al. 2006

23 what about the brains of users? Question Are the brains of long-term methamphetamine users different from controls?

25 Johanson et al. 2006, Psychopharmacology 85,

26 Summary of PET imaging findings Findings Investigators DAT & VMAT BP in striatum Johanson et al. 2006; McCann et al. 1998, 2008; Sekine et al. 2001; Volkow et al. 2001a D2/D3 BP in striatum Lee et al. 2009; Volkow et al. 2001b VMAT-2 BP in striatum Boileau et al. 2008; Hart et al. 2012, Neuropsychopharmacology 37,

27 more critical question Question What are the implications for cognitive functioning?

28 Determining impairment Cognitive performance has to be compared against a normative score taking into consideration the individual s age and level of education Only 1 study found MA users to be impaired (Kalechstein et al. 2003) Performance in at least one domain for 7 of 27 MA users met this impairment criterion, whereas this number was 2 of 18 for controls These findings have yet to be replicated

29 Summary of cognitive findings Human lab data: MA improves cognitive performance PET findings: striatal DAT density lower in MA users Data from MRI and fmri studies also revealed some differences between the groups, but few replications of findings Cognitive functioning abstinent users: overwhelmingly impairment not demonstrated

30 My goal is not to minimize real problems of MA abuse Functional Problems Sleep disruptions Social and occupational disruptions» but not unique to MA abuse

31 Implications Scientific decreased likelihood of documenting actual pattern of cognitive effects caused by the drug Treatment belief that users can t engage in cognitive-behavioral therapy» such concerns are not warranted Public Policy several governments have taken drastic measures in an effort to limit the use of MA (and other drugs) the war on drugs

32 The United States now has: A greater proportion of our citizens in prison than any other nation 5% of world s population, but 25% of world s prison population Number Sentenced Prisoners in Federal and State Institutions Year

Hyper-incarceration not evenly distributed In 2010: 1 in 8 black males aged 20-29 was in prison or jail 1 in 26 Hispanic males and 1 in 63 white males 1 in 3

33 Hyper-incarceration not evenly distributed In 2010: 1 in 8 black males aged was in prison or jail 1 in 26 Hispanic males and 1 in 63 white males 1 in 3 black males born today will spend time in prison Hispanic counterparts 17% white counterparts 6% Black males represent 6% of gen. pop. but 35% of incarcerated pop.

34 My role as a scientist? National Institute on Drug Abuse Mission to lead the Nation in bringing the power of science to bear on drug abuse and addiction Annual budget > $1 billion Funds about 90% of all research on drugs of abuse

35 Lost Car Keys Analogy It is difficult to get a man to understand something when his salary depends upon his not understanding it. - Upton Sinclair

36 This coupled with the fact that Scientists tend to err on the side of caution (= bad effects) as if this isn t without consequence In reality, helped to create an environment where: certain drugs deemed evil and any use considered pathological an unrealistic focus on eliminating drug use at any cost» e.g., a drug-free America

37 Solution: Decriminalize & Educate Legalization vs Decriminalization Legalization e.g. alcohol and tobacco Decriminalization acquisition, use, and possession of drugs can be punished by citation, e.g., traffic violations Sales of all illicit drugs remain criminal offenses Realistic Education

38 Take-home Message Many assumptions about methamphetamine are simply not supported by evidence from research Does provide, however, an example of how to launch a worldwide drug menace Current knowledge is incomplete Still, we must act (e.g., treatment, education, policy) Be prepared to alter our actions as new, more complete knowledge dictates Finally, use your common sense If a story seems incredible, it probably is

Drug Epidemics: Things You Need to Know. Prof. Carl L. Hart Columbia University. drcarlhart.com

Drug Epidemics: Things You Need to Know Prof. Carl L. Hart Columbia University drcarlhart.com 10 MA vs. $20 Choice (max =10) 8 6 4 2 drug users can and do behave rationally 0 Drug Money Reinforcer Things