Archive for the ‘SCIENCE’ category

Neuropsychological Deficits: Fact and Artifact About Marijuana Tests

April 15th, 2014

By Mitch Earleywine, Ph.D
State University of New York at Albany
Chair, NORML board of directors

A new study claims to show small deficits on neuropsychological tests in college students who started smoking marijuana early in life. It might get a lot of press. Prohibitionists love to bang the drum of marijuana-related cognitive deficits, so I’d like NORMLites to know how to make sense of this sort of research. The recurring themes in this literature involve several alternative explanations that never seem to dawn on journalists. These results often arise from artifacts of the study rather than physiological effects of the plant. I’d like to focus on a few: other drug use, dozens of statistical tests, the incentives for performance, and the demands communicated by the experimenters.NWA Canada Prohibition Car

The latest paper of this type is actually pretty good. Researchers studied over 30 people aged 18-20 who started using before age 17 (their average starting age was around 15) and who smoked at least 5 days per week for at least a year. They compared them to a comparable bunch of non-users. I hate to see 15-year-olds using anything psychoactive, even caffeine. Spending full days in high school with less than optimal memory functioning is no way to lay the groundwork for a superb life. I admit that I want these same people to grow up and be the next generation of activists, so feel free to call me selfish when I emphasize NORML’s consistent message: THE PLANT IS NOT FOR KIDS WHO LACK MEDICAL NECESSITY.

OTHER DRUG USE?
First, we have to keep other drug use in mind. Unfortunately, the marijuana group in this study got drunk more than 4 times as much in the last six months as the controls. Given what we know about binge drinking and neuropsychological functioning, it’s going to be hard to attribute any differences between these groups to the plant. It’s just as likely that any deficits stem from pounding beers. Studying cannabis users who aren’t so involved with alcohol would help address neuropsychological functioning much better.

HOW MANY TESTS?
In addition, we should always consider the number of measures in any study. Many of these neuropsychological tasks have multiple trials that can be scored multiple ways. The more statistical tests you run, the more likely it is that you’ll find a statistically significant difference by chance. It’s kind of like flipping coins. It’s rare to flip four heads in a row. But if you flip a coin a thousand times, odds are high that somewhere in the list of a thousand results will be four heads in a row. These investigators got 48 different test scores out of the participants. You’d expect at least 2 of them to be significant just by chance. They found differences on 14 different scores, suggesting that something’s going on, but we’re not sure which results are the “real” differences and which ones arose by accident. (That’s why we replicate studies like this.) And, as I mentioned, it might all be because of the booze.

WHY WOULD ANYONE DO ALL THESE TESTS?
We also have to consider incentives for performance. Most researchers bring participants to the lab for a fixed fee and ask them to crank out a bunch of crazy puzzles and memory assessments. It’s unclear why people would feel compelled to strain their brains. The authors of this study were kind enough to mention some relevant work by my friend (and former student) Dr. Rayna Macher. Dr. Macher showed that cannabis users respond best when you make the effort worth their while. She focused on people who used the plant at least four times per week for a year or more. She read one group some standard instructions for a memory test. The other group got the regular instructions plus an additional sentence: “It is important that you try your very best on these tasks, because this research will be used to support legislation on marijuana policy.”

As you’d guess, this simple sentence fired them up. Compared to cannabis users who didn’t hear that sentence, they performed better on 3 out of 10 measures. (You’d expect less than one difference by chance.) And compared to the non-users, the folks who got the incentive sentence did just as well on all the tests. For those who didn’t hear the incentive sentence, users did less well than non-users on 1 of the 10.

I know that prohibitionists are going to try to call this amotivation. (See my rant on that when you get a chance) I call it putting effort where it pays. But given what we know about how these studies can hamper the reform of marijuana laws, users everywhere should do their best on all tests whenever they get the chance.

WE OFTEN DO WHAT EXPERIMENTERS EXPECT OF US
Last but not least, we have to consider the demands communicated by the experimenter. Decades of data now support the idea that people often do what others expect them to do, especially if they believe the expectation, too. Another friend and former student, Dr. Alison Looby De Young, showed that these expectations are critical in studies of neuropsychological performance and cannabis. She gave a neuropsychological battery to men who had used cannabis at least three times per week for the last two years. One group of men read instructions that said that cannabis had no impact on their performance on these tests. Another group read instructions that said that cannabis was going to make them perform poorly. You guessed it, those men who heard they were going to flub the tests performed worse on 2 of the 4 tests. (You’d expect less than one difference by chance). As you might imagine, some laboratories communicate their expectations about cannabis and cognitive function subtly or not so subtly. Some participants are bound to behave accordingly. So what looks like a cognitive deficit is just an artifact of the laboratory environment where experimenters stare daggers at cannabis users.

In the end, I’m glad that researchers do this work, but these effects are too small and fleeting to justify prohibition. We already know that cannabis isn’t for healthy kids. People who get heavily involved with the plant early in life might not perform as well as those who never touch cannabis even if investigators control for other drug use, AND use a sensible number of tests, AND provide appropriate incentives, AND communicate a reasonable expectation.

But how many people should go to jail for that?

If you said, “None,” you’ve done an excellent job on an important cognitive test.

Study: Frequent Cannabis Consumers Less Likely To Engage In Problematic Alcohol Use

April 15th, 2014

Those who report consuming cannabis two or three times per week are less likely to engage in at risk drinking behavior, according to data published online in The American Journal of Addictions.

Investigators from Sweden’s Lund University, Department of Clinical Sciences, analyzed data from a nationwide survey on alcohol and drug use conducted by the National Institute of Public Health. Over 22,000 respondents between the ages of 15 and 64 participated in the survey.

Researchers reported that frequent cannabis consumers (defined as having used cannabis two or three times per week) were less likely to engage in hazardous drinking practices compared to infrequent users (those who reported having consumed cannabis fewer than four times per month).

They concluded: “In the present study, it has been shown that, in the Swedish general population, cannabis use is associated with a higher prevalence of other illicit drug use and hazardous alcohol use. Among cannabis users, frequent cannabis use is associated with a higher prevalence of other illicit drug use and a lower prevalence of hazardous alcohol use when compared to occasional cannabis use. … … The inverse relationship between the frequency of cannabis use and hazardous drinking has not been reported before to our knowledge. … This may indicate that cannabis users and alcohol users are different groups, albeit with a high degree of overlap between groups, with different characteristics and clinical needs.”

A review paper published in February in the journal Alcohol and Alcoholism similarly acknowledged that some cannabis consumers likely substitute the plant for alcohol. It concluded: “While more research and improved study designs are needed to better identify the extent and impact of cannabis substitution on those affected by AUD (alcohol use disorders), cannabis does appear to be a potential substitute for alcohol. Perhaps more importantly, cannabis is both safer and potentially less addictive than benzodiazepines and other pharmaceuticals that have been evaluated as substitutes for alcohol.”

An abstract of the study, “Alcohol and drug use in groups of cannabis users: Results from a survey on drug use in the Swedish general population,” appears here.

Study: Enactment Of Medical Cannabis Laws Not Associated With Higher Crime Rates

April 8th, 2014

The enactment of medicinal cannabis laws is not associated with any rise in statewide criminal activity and may even be related to reductions in incidences of violent crime, according to data published online in the journal PLoS ONE.

Researchers at the University of Texas at Dallas tracked crime rates across all 50 states between the years between 1990 and 2006, a time period during which 11 states legalized marijuana for medical use. Authors reviewed FBI data to determine whether there existed any association between the passage of medicinal cannabis laws and varying rates of statewide criminal activity, specifically reported crimes of homicide, rape, robbery, assault, burglary, larceny, and auto theft.

Investigators reported that the passage of medical marijuana laws was not associated with an increase in any of the seven crime types assessed, but that liberalized laws were associated with decreases in certain types of violent crime.

“The central finding gleaned from the present study was that MML (medical marijuana legalization) is not predictive of higher crime rates and may be related to reductions in rates of homicide and assault,” authors reported. “Interestingly, robbery and burglary rates were unaffected by medicinal marijuana legislation, which runs counter to the claim that dispensaries and grow houses lead to an increase in victimization due to the opportunity structures linked to the amount of drugs and cash that are present. Although, this is in line with prior research suggesting that medical marijuana dispensaries may actually reduce crime in the immediate vicinity.”

Researchers concluded: “Medical marijuana laws were not found to have a crime exacerbating effect on any of the seven crime types. On the contrary, our findings indicated that MML precedes a reduction in homicide and assault. … In sum, these findings run counter to arguments suggesting the legalization of marijuana for medical purposes poses a danger to public health in terms of exposure to violent crime and property crimes.”

Full text of the study, “The Effect of Medical Marijuana Laws on Crime: Evidence from State Panel Data, 1990-2006,” appears online here.

WebMD Poll: Medical Community Backs Legalizing Cannabis

April 4th, 2014

An estimated 70 percent of physicians acknowledge the therapeutic qualities of cannabis and over half believe that the plant should also be legal for medical purposes, according to survey data released this week by WebMD/Medscape.

Sixty-nine percent of respondents say that cannabis can help in the treatment of specific diseases and 67 percent say that the plant should be available as a legal therapeutic option for patients.

Oncologists and hematologists were most likely to express support for the use of cannabis for medical purposes, with 82 percent of those surveyed endorsing the plant’s therapeutic use. Rheumatologists (54 percent) were least likely to say the cannabis provides therapeutic benefits.

Over 1,500 physicians representing more than 12 specialty areas participated in the survey which possesses a margin of error of +/- 2.5 percent.

Supposed ‘Medical Marijuana’ Measures In Alabama, Utah Are Anything But

March 25th, 2014

At a public signing ceremony today, Utah’s Republican Gov. Gary Herbert will approve House Bill 105 — aka “Charlee’s Law.” The law, and others like it, ostensibly allows children with treatment-resistant pediatric epilepsy access to extracts of the marijuana plant high in the cannabinoid cannabidiol (CBD).

While some media outlets are reporting that the passage of these measures are akin to ‘approving medical marijuana,’ such claims are far from accurate.

Specifically, Utah’s HB 105 — which takes effect on July 1 — is largely unworkable. As written, the law only exempts from state prosecution those with “intractable epilepsy” who possess a cannabis extract that contains more than 15 percent CBD and no more than 0.3 percent THC. Patients must receive a written recommendation from a Utah board certified neurologist and be registered with the state Department of Health before seeking such extracts, which for the time being may only be procured from outside of the state. The extracts must be produced in a lab that possess a state-license to manufacture such products.

While this language may appear to allow Utah patients to procure CBD products in neighboring medical cannabis states like Colorado, the likelihood of this scenario is highly doubtful. Colorado’s medical marijuana law only allows those who are state residents and who possess a state-issued patient identification card to legally purchase such products. In other words, Utah parents would have to violate Colorado law to obtain high-CBD extracts (which are likely to only be available from a medical dispensary, not a retail cannabis market). Colorado medical marijuana dispensaries would also be in violation of not just the letter of the law, but also the spirit of the law by providing a product they know is intended to be transported across state lines — a clear violation of the guidelines put forward in the August 2013 Department of Justice memo which call for “preventing the diversion of marijuana from states where it is legal in some form to other states.”

Utah’s forthcoming law also calls on the state Department of Agriculture “to grow or cultivate industrial hemp for the purpose of
agricultural or academic research,” ostensibly for the purpose of one-day producing high-CBD cannabis medicines. However, it remains to be seen whether such industrial crops can yield therapeutically effective CBD extracts or whether federal lawmakers would even allow such a state-sponsored research project to move forward.

In Alabama, members of the House and Senate unanimously approved CBD-specific legislation, Senate Bill 174 aka “Carley’s Laws,” late last week. Republican Gov. Robert Bently has announced his intent to sign the measure into law.

However, like the Utah law, Alabama’s forthcoming law will also be largely unworkable for those who seek to benefit from it. The measure appropriates $1 million dollars for University of Alabama-sponsored research in CBD extracts. Whether such research will actually take place is another story. Because CBD is, like the cannabis plant itself, classified under federal law as a schedule I controlled substance, multiple federal agencies — including the FDA, DEA, NIDA (US National Institute of Drug Abuse), and PHS (Public Health Service) must all sign off on any clinical investigation of the drug — a process that typically takes several years and often ends with federal regulators rejecting the protocol outright. Yet, under “Carley’s Law,” patients may only legally access CBD under if it is “prescribed” during the course of such a federally approved clinical trial.

Nevertheless, despite these obvious limitations in implementation, lawmakers in various other states — including Florida, Kentucky, Minnesota, South Carolina, and Wisconsin — are considering passing similar measures. (A similar Georgia measure died when lawmakers adjourned late last week.) While the passage of these measures may pose symbolic victories for legislators, they fail to provide tangible benefits to the constituents that they are intended to serve.

Study: Drug Dogs Most Likely To Err In Traffic Stop Scenarios

March 24th, 2014

Dogs trained to detect the presence of illegal drugs are most likely to provide false alerts in situations involving the search of a motor vehicle, according to the findings of a study published online in the journal Forensic Science International.

A team of researchers from the United States and Poland assessed the ability of trained drug sniffing dogs to accurately detect the presence controlled substances – including marijuana, hashish, amphetamines, cocaine and heroin – in various environments.

Dogs were most likely to correctly identify the presence of contraband, particularly marijuana, during searches of individual rooms. If the dog had previous exposure to the room prior to the search, it was least likely to provide a false alert (83 percent correct identifications versus 10 percent false alerts).

Dogs were far less reliable in scenarios designed to mimic real-world traffic stops. In situations where dogs accessed the perimeter of a motor vehicle, the animals accurately alerted to the presence contraband only 64 percent of the time. Fifteen percent of the time dogs failed to recognize the presence of illicit drugs. Twenty-two percent of the time the dogs indicated that illegal drugs were present when they were not.

Drug dogs’ failure rates were even more pronounced in situations where the animals had access to the inside of a vehicle. In this scenario, dogs correctly responded to the presence of contraband only 58 percent of time. They provided false alerts 36 percent of time.

Previous studies have similarly documented drug dogs’ tendency to provide false alerts. In 2011, researchers at the University of California at Davis reported that the performance of drug-sniffing dogs is significantly influenced by whether or not their handlers believe illicit substances are present. That same year, a review of Australian government statistics, published in the Sydney Morning Herald, found that some 80 percent of drug dog alerts in New South Wales yielded no illicit substances.

In 2005, the United States Supreme Court ruled in Illinois v Caballes that an alert from a police dog during a traffic stop provides a constitutional basis for law enforcement to search the interior of the vehicle.

Michigan: Regulators Expand State’s Medical Marijuana Law To Include Patients With PTSD

March 18th, 2014

Michigan physicians may now authorize cannabis for the treatment of post traumatic stress.

Members of the Medical Marihuana Review Panel voted 6 to 2 to expand the state’s list of qualifying conditions to include PTSD. The Director of the Michigan Department of Licensing and Regulatory Affairs has signed off on the recommendation.

This is the first time that regulators have expanded the state’s list of qualifying conditions since voters initially legalized the physician authorized use of cannabis in 2008.

Six other states — Connecticut, Delaware, Maine, New Mexico, Nevada, and Oregon — explicitly allow for the use of cannabis to treat symptoms of post-traumatic stress. Nevada regulators expanded their law to include PTSD earlier this year. Oregon and Maine lawmakers amended their medical cannabis laws last year to include post-traumatic stress.

California physicians may recommend medical cannabis at their discretion.

Clinical trial data published in the May issue of the journal Molecular Psychiatry theorized that cannabinoid-based therapies would likely comprise the “next generation of evidence-based treatments for PTSD (post-traumatic stress disorder).”

Post-traumatic stress syndrome is an anxiety disorder that is estimated to impact some eight million Americans annually. To date, there are no pharmaceutical treatments specifically designed or approved to target symptoms of PTSD.

Last week, federal officials at the Public Health Service approved the use of cannabis in a privately funded pilot trial at the University of Arizona College of Medicine to assess its potential risks and benefits in war veterans suffering from PTSD, including the plant’s potential impact on subjects’ anxiety, suicidality, and depression. Although the study was initially approved by the FDA in 2011, neither PHS nor the US National Institute on Drug Abuse (NIDA) signed off on the protocol until this month. Both agencies, as well as the US DEA, must approve any clinical trial involving cannabis.

RAND Study: Marijuana Use Rises While Consumption Of Cocaine, Methamphetamine Falls

March 18th, 2014

A rise in the self-reported consumption of cannabis during the years 2006 to 2010 corresponds with a significant decline in Americans’ use of cocaine and methamphetamine during this same time period, according to a new RAND study commissioned by the White House Office of National Drug Control Policy (ONDCP).

Researchers estimate that Americans increased their consumption of cannabis by approximately 30 percent during the years 2006 to 2010. During this same time, authors estimated that the public’s use of cocaine and methamphetamine declined, with Americans’ use of cocaine falling by half.

Americans’ consumption of heroin remained largely stable throughout the decade, the study reported. According to statistics compiled by the US Substance Abuse And Mental Health Services Administration, an estimated 4.5 million Americans have tried heroin in their lifetimes. By comparison, an estimated 12 million Americans have tried methamphetamine, 37.5 million have tried cocaine, and 111 million have consumed cannabis.

Authors estimated that Americans spent approximately one trillion dollars on the purchase of cocaine, heroin, marijuana and methamphetamine between 2000 and 2010.

Commenting on the report, NORML Deputy Director Paul Armentano said, “These figures belie that notion that marijuana exposure is an alleged ‘gateway’ to the use of other illicit substances and instead suggest that for some people, cannabis may be a substitute for other so-called ‘hard drugs’ or even an exit drug.”

Survey data published in 2013 in the journal Addiction Research & Theory reported that among a cohort of medical marijuana consumers, 75 percent of subjects acknowledged that they used cannabis it as a substitute for prescription drugs, alcohol, or some other illicit substance.

A 2010 study published in the Harm Reduction Journal reported that cannabis-using adults enrolled in substance abuse treatment programs fared equally or better than nonusers in various outcome categories, including treatment completion.

Full text of the study, “”What America’s Users Spend on Illegal Drugs, 2000-2010,” is available online from the Office of National Drug Control Policy here.

Study: Inhaled Cannabis Mitigates Parkinson’s Disease Symptoms

March 17th, 2014

Inhaling whole-plant cannabis provides symptomatic relief in patients with Parkinson’s disease (PD), according to observational trial data published in the March/April edition of the journal Clinical Neuropharmacology. Parkinson’s is a progressive disorder of the central nervous system that results in tremor, slowed movement, and muscle rigidity.

Investigators at Tel Aviv University, Department of Neurology evaluated Parkinson’s disease symptoms in 22 patients at baseline and 30-minutes after inhaling cannabis.

Researchers reported that inhaled cannabis was associated with “significant improvement after treatment in tremor, rigidity, and bradykinsea (slowness of movement). There was also significant improvement of sleep and pain scores. No significant adverse effects of the drug were observed.”

They concluded: “[T]his observational study is the first to report an amelioration of both motor and non–motor symptoms in patients with PD treated with cannabis. The study opens new venues for treatment strategies in PD especially in patients refractory to current medications.”

Israel has formally allowed for the licensed production and distribution of the substance for therapeutic purposes since 2011.

An abstract of the study, “Cannabis (Medical Marijuana) Treatment for Motor and Non–Motor Symptoms of Parkinson Disease: An Open-Label Observational Study,” is online here.

Patients Ought To Be Skeptical Of Proposed CBD-Only Legislation — Here’s Why

March 6th, 2014

In recent weeks, lawmakers in several states have moved forward with legislative proposals to permit specific strains and/or extracts of cannabis possessing high quantities of the cannabinoid cannabidiol (CBD), but otherwise maintaining criminal prohibitions on the whole plant.

But is this new direction in the best interest of patients? As I wrote in a recent column for Alternet.org (republished with permission by Cannabis Now under the title “Patients Ought To Be Skeptical Of Proposed CBD-Only Legislation — Here’s Why”), I believe the answer is ‘no.’

Ultimately, patients should not be unnecessarily forced to decide between either accessing the whole plant or its isolated components. They should have safe, legal access to both, and politicians, even well-intentioned ones, should not restrict patients’ right to choose the most suitable option.

Below are excerpts from my commentary. You can read the entire text here.

Patients Ought To Be Skeptical Of Proposed CBD-Only Legislation — Here’s Why
via Cannabis Now

[excerpt] If the plant ain’t broke, why fix it?

For longtime marijuana law reformers, the ongoing political conversation surrounding CBD is instructive. It makes it clear that many politicians’ public opposition to the idea of patients using marijuana therapeutically isn’t because of supposed unanswered questions surrounding the plant’s safety or efficacy. Rather, it is because lawmakers oppose the idea of some people getting high from a naturally growing herb. (The fact that patients can get equally high or even higher from FDA-approved synthetic THC has, for whatever reason, never been an expressed concern of either lawmakers or prohibitionists.) After all, the very same politicians who argue that marijuana isn’t medicine because it hasn’t been approved by the FDA or who allege that the substance hasn’t yet been subjected to sufficient scientific scrutiny utter no such public objections to the idea of legalizing patient access to CBD – a schedule I compound that hasn’t been reviewed, much less approved by the FDA, and that has been clinically studied far less than cannabis.

Perhaps most ironically is that were it not for the advent of legalized whole plant marijuana, a policy change publicly opposed by many present day CBD-only political advocates, lawmakers (and anti-pot groups like SAM) today wouldn’t be aware of CBD, much less advocating for it. The reality is that it was the stakeholders in medical marijuana states, and those who provide for them, who have done the most to explore and promote cannabidiol as a legitimate therapeutic agent. And they were able to do so because they, unlike most federally licensed medical researchers, had access to the whole plant.

We’ve been down this road before. Not long ago, lawmakers and anti-marijuana zealots were dismissing patients’ desire to access the marijuana plant because they alleged that the THC-pill Marinol could adequately meet patients’ needs. Patients and their advocates were skeptical of lawmakers’ claims then, and properly so. Now many of these same politicians are once again dismissing patients’ calls for whole plant medicine by claiming that products and strains containing CBD alone only will suffice. Patients and their advocates ought to be equally skeptical once again.