Father's incarceration associated with elevated risks of marijuana and other illegal drug use, study finds

— In a recently published study in the journal Addiction, researchers from Bowling Green State University report evidence of an association between father's incarceration and substantially elevated risks for illegal drug use in adolescence and early adulthood.

The number of persons incarcerated in the United States has sharply risen over the past several decades, from about 250,000 in 1975 to 2,250,000 in 2006. So too has the number of children with incarcerated parents, particularly fathers. The consequences of father's incarceration for their children, families, and communities are of increasing concern to researchers, policy makers, and practitioners.

Using data from the National Longitudinal Study of Adolescent Health, a nationally representative sample of adolescents in schools in 1995, who were periodically followed into their early to mid-20s, this new study examined the association between having an incarcerated biological father and marijuana and other illegal drug use. Over 51% of young men, and almost 40% of young women, whose biological fathers had a history of incarceration reported using marijuana, compared to 38% and 28%, respectively, of comparable men and women whose fathers were never incarcerated. Youth with incarcerated fathers also exhibited elevated trajectories of marijuana usage that extended into their mid-twenties, compared to other youth whose marijuana use peaked at about age 20. Biological father's incarceration was also found to be associated with elevated use of other illegal drugs, such as cocaine, heroin, and methamphetamines.

Given that having a father in prison is an increasingly common event, this study's findings suggest that a substantial number of young people in the USA are at risk for drug use. Increased drug use is closely linked to a number of adverse outcomes, including illegal drug market activity, increased crime and incarceration rates, lost work productivity, and costly substance abuse treatment. "Long-term drug use may exacerbate many other problems faced by disadvantaged youth, including mental health issues, delinquency, dropping out of school, domestic violence and poverty," says the study's lead author, Dr. Michael Roettger, a Postdoctoral Fellow with the National Center for Family and Marriage Research. Roettger notes that "this is of particular concern within poor and minority communities where incarcerations are disproportionately located."

The researchers are careful to note, however, that this is a non-experimental study, and that the relationships observed are associations, and should not be taken to indicate a causal process. "Further research is needed to more fully examine if it is father's incarceration, or other closely related factors such as father's criminality, family histories of drug use, or stresses associated with family instability, that are driving these detrimental relationships" cautions Dr. Raymond Swisher, one of the study's co-authors. Danielle Kuhl and Jorge Chavez, also of Bowling Green State University, are also co-authors on the study.

The numbers show the potential size of the problem. In 2006, nearly 7.5 million children were estimated to have a parent currently in prison or on probation/parole. Expressed in terms of cumulative risk, 13% of young adults in the U.S. report that their fathers had spent time in prison during their childhoods.


Journal Reference:

  1. Michael E. Roettger, Raymond R. Swisher, Danielle C. Kuhl, Jorge Chavez. Paternal incarceration and trajectories of marijuana and other illegal drug use from adolescence into young adulthood: evidence from longitudinal panels of males and females in the United States. Addiction, 2010; DOI: 10.1111/j.1360-0443.2010.03110.

Compound boosts marijuana-like chemical in the body to relieve pain at injury site

 American and Italian researchers have found that a novel drug allows anandamide — a marijuana-like chemical in the body — to effectively control pain at the site of an injury.

Led by Daniele Piomelli, the Louise Turner Arnold Chair in Neurosciences and director of the Center for Drug Discovery at UC Irvine, the study suggests that such compounds could form the basis of pain medications that don't produce sedation, addiction or other central nervous system side effects common with existing painkillers, such as opiates.

"These findings raise hope that the analgesic properties of marijuana can be harnessed to curb pain," Piomelli said. "Marijuana itself is sometimes used in clinical settings for pain relief but causes many unwanted effects. However, specific drugs that amplify the actions of natural, marijuana-like chemicals are showing great promise."

For the study, which appears in the Sept. 19 online version of Nature Neuroscience, rats and mice were given a drug created by Piomelli and colleagues at the Italian universities of Urbino and Parma. The researchers discovered that the compound, URB937, did not enter the central nervous system but simply boosted the levels of anandamide in peripheral tissues. Still, it produced a profound analgesic effect for both acute and chronic pain. This was surprising, since anandamide had been thought to only work in the brain.

The synthetic drug inhibits FAAH, an enzyme in the body that breaks down anandamide, dubbed "the bliss molecule" for its similarities to the active ingredient in marijuana. A neurotransmitter that's part of the endocannabinoid system, anandamide has been shown in studies by Piomelli and others to play analgesic, antianxiety and antidepressant roles. It's also important in regulating food consumption. Blocking FAAH activity enhances the effects of anandamide without generating the "high" seen with marijuana.

Piomelli and his team are now collaborating with drug discovery specialists at the Italian Institute of Technology, in Genoa, to develop the new compound — which is protected by a patent application — into a clinically useful medication.

Researchers from UCI, the University of Georgia, the University of Naples, the University of Parma, the University of Urbino and the Italian Institute of Technology participated in the study, which was supported by the National Institute on Drug Abuse and the Italian Ministry of Public Education.


Journal Reference:

  1. Jason R Clapper, Guillermo Moreno-Sanz, Roberto Russo, Ana Guijarro, Federica Vacondio, Andrea Duranti, Andrea Tontini, Silvano Sanchini, Natale R Sciolino, Jessica M Spradley, Andrea G Hohmann, Antonio Calignano, Marco Mor, Giorgio Tarzia, Daniele Piomelli. Anandamide suppresses pain initiation through a peripheral endocannabinoid mechanism. Nature Neuroscience, 2010; DOI: 10.1038/nn.2632

Medicinal cannabis review highlights dilemmas facing healthcare professionals

Nurses have a responsibility to respect and support patients who use cannabis for medicinal purposes, but must stay within the law and follow professional guidance at all times, according to a research review in the September issue of the Journal of Clinical Nursing.

Dr Anita Green and Dr Kay De-Vries studied more than 50 published papers, together with professional and Government guidance documents, official reports and media coverage, from 1996 to 2009.

They point out that the fact that the cannabis is usually obtained illegally can have consequences for those who choose to use it for its medicinal value and create real dilemmas for the nurses and other healthcare professionals who care for them. For example, it is vital that any drug use is recorded on the patient's medical records for their own safety, but many patients may be unhappy for that to happen.

"Nurses are increasingly likely to deal with patients using medicinal cannabis and it is important that they put their personal views to one side and deal with the health consequences of that drug use" says Dr Green, a Nurse Consultant for the Sussex Partnership NHS Foundation Trust and Visiting Fellow at the University of Brighton.

"The literature on the medicinal use of cannabis repeatedly refers to changes that could improve people's quality of life, like improved sleep, a better appetite and reduced depression, and these perceived benefits have led to greater usage.

"However, it also states that far more research is needed and it is very important that patients are fully aware of the legal consequences of taking cannabis, together with the physical and psychological effects it may have on them.

"Nurses and other healthcare professionals need to be well informed about the medicinal effects of cannabis and how this can interact with other medication the patient is being prescribed. It is also vital that the patient's cannabis use is accurately documented in their records and that other professionals, such as pharmacists, doctors and substance misuse teams are brought in to provide advice, with their permission."

Cannabis, which has been widely used as a herbal remedy since ancient times, was brought to Western Europe at the beginning of the 19th century by Napoleonic soldiers who had been fighting in North Africa.

Its medicinal use was advocated in European and American medical articles as far back as 1849, but was banned in the UK in 1928 after UK delegates at an international opium conference were persuaded that cannabis caused insanity.

"Our review shows that the general view of integrating cannabis derivative medications into mainstream medical use remains extremely cautious" says Dr Green. "Most of the research we studied indicated that there was a need for more clinical trials examining the optimal administration routes and dosing regimes.

"It is repeatedly pointed out in the literature that the development of cannabis and isolated synthetic cannaboids for medicinal purposes is still in its infancy and has a long way to go.

"The aim of our study was to review the literature and to raise awareness of the questions and dilemmas facing the medical profession, specifically nurses, when it comes to caring for patients who use cannabis for medicinal reasons.

"We hope that the review — which looked at the research published into the pharmacological qualities of cannabis and its use in palliative care, for example cancer, multiple sclerosis and motor neurone disease — will stimulate further debate.

"In the meantime, it is vital that nurses and other healthcare professionals act within the law and follow the guidance laid down by their professional organisations."

The authors say that the review highlights the real dilemmas created for the medical profession by the medicinal use of cannabis.

"Nurses have a caring responsibility to maximise their patients' quality of life, but should they also be reminding them that the medicinal use of cannabis remains illegal?" asks Dr Green. "Or should they respect the patient's right to take the drug and just make sure that it does not conflict with any other treatment, such as prescribed medication?

"It is clear that further debate is essential and that nurses need ongoing support and guidance to help them tackle these thorny dilemmas and provide the best healthcare they can for their patients without compromising their professional integrity."


Journal Reference:

  1. Anita J Green, Kay De-Vries. Cannabis use in palliative care – an examination of the evidence and the implications for nurses. Journal of Clinical Nursing, 2010; 19 (17-18): 2454 DOI: 10.1111/j.1365-2702.2010.03274.x

Risk of marijuana's 'gateway effect' overblown, new research shows

 New research from the University of New Hampshire shows that the "gateway effect" of marijuana — that teenagers who use marijuana are more likely to move on to harder illicit drugs as young adults — is overblown.

Whether teenagers who smoked pot will use other illicit drugs as young adults has more to do with life factors such as employment status and stress, according to the new research. In fact, the strongest predictor of whether someone will use other illicit drugs is their race/ethnicity, not whether they ever used marijuana.

Conducted by UNH associate professors of sociology Karen Van Gundy and Cesar Rebellon, the research appears in the September 2010 issue of the Journal of Health and Social Behavior.

"In light of these findings, we urge U.S. drug control policymakers to consider stress and life-course approaches in their pursuit of solutions to the 'drug problem,' " Van Gundy and Rebellon say.

The researchers used survey data from 1,286 young adults who attended Miami-Dade public schools in the 1990s. Within the final sample, 26 percent of the respondents are African American, 44 percent are Hispanic, and 30 percent are non-Hispanic white.

The researchers found that young adults who did not graduate from high school or attend college were more likely to have used marijuana as teenagers and other illicit substances in young adulthood. In addition, those who used marijuana as teenagers and were unemployed following high school were more likely to use other illicit drugs.

However, the association between teenage marijuana use and other illicit drug abuse by young adults fades once stresses, such as unemployment, diminish.

"Employment in young adulthood can protect people by 'closing' the marijuana gateway, so over-criminalizing youth marijuana use might create more serious problems if it interferes with later employment opportunities," Van Gundy says.

In addition, once young adults reach age 21, the gateway effect subsides entirely.

"While marijuana use may serve as a gateway to other illicit drug use in adolescence, our results indicate that the effect may be short-lived, subsiding by age 21. Interestingly, age emerges as a protective status above and beyond the other life statuses and conditions considered here. We find that respondents 'age out' of marijuana's gateway effect regardless of early teen stress exposure or education, work, or family statuses," the researchers say.

The researchers found that the strongest predictor of other illicit drug use appears to be race-ethnicity, not prior use of marijuana. Non-Hispanic whites show the greatest odds of other illicit substance use, followed by Hispanics, and then by African Americans.


Journal Reference:

  1. Karen Van Gundy, Cesar Rebellon. A Life-course Perspective on the 'Gateway Hypothesis'. Journal of Health and Social Behavior, September 2010

Hispanic kids show greater risk of substance use, study suggests

Hispanic middle school students may be more likely to smoke, drink or use marijuana than their peers of other races and ethnicities, whereas Asian students seem to have the lowest risk, according to new research in the September issue of the Journal of Studies on Alcohol and Drugs.

The study, of 5,500 seventh- and eighth-graders at 16 California schools, found that young Hispanic adolescents were more likely than other students to have ever used alcohol, cigarettes or marijuana. Asian students, meanwhile, had the lowest rates of substance use compared with Hispanic, white and African American students.

Moreover, the study found that some of the factors that seemed to influence kids' odds of substance use also varied by race and ethnicity.

Among Hispanic youth, it was personal factors that were linked to the risk of substance use — including their confidence in their ability to "say no" and whether they believed drinking, smoking and drug use had more negative consequences.

In contrast, a wider range of factors was linked to Asian teens' relatively low rates of substance use — not only those same personal-level factors but also respect for their parents and lower rates of substance use among their older siblings and peers.

The findings point to some important issues that could be addressed in substance-use prevention programs for middle school students, according to Regina A. Shih, Ph.D., and colleagues at the research organization RAND Corporation.

"Most interventions haven't really been tailored to be culturally appropriate," Shih explained. For example, "skills training," where kids learn how to resist pressure to smoke, drink or use drugs, could help address one of the personal factors that was connected to Hispanic students' higher rates of substance use.

Similarly, interventions that encourage positive parent-child communication and boost kids' sense of responsibility to their parents might help maintain lower rates of substance use — and could be particularly effective for young Asian teens.

Shih said, however, that the researchers are not suggesting that such targeted efforts only be offered to students of certain ethnicities — but that they could be widely applied in prevention programs to help the broadest range of kids possible. Many existing interventions target these types of personal factors and address adolescent and parent communication. "It is important for parents to be aware that many youth initiate substance use during the middle school years, and parents can help their teen make healthier choices by monitoring their activities and talking with them about these issues," Shih said.

Of all students in the study, 22 percent said they had ever used alcohol, 10 percent admitted to smoking at some point, and 7 percent reported marijuana use. In general, the odds of substance use were highest among Hispanic students, lowest among Asians and not statistically different between white and African American students.

When it came to drinking, for example, 26 percent of Hispanic students said they had ever tried alcohol, versus 21 percent of black students, 18 percent of whites and just below 10 percent of Asians.

When the researchers accounted for several other factors — including gender and students' family structures — Hispanic middle schoolers still had a higher probability, and Asian students still had a lower probability, of ever using cigarettes, alcohol or marijuana, compared with white students.

Using this large longitudinal sample, Shih's team will be able to continue to follow young adolescents over time to see which personal, family and school factors seem to predict the initiation or worsening of teens' smoking, drinking or drug use.

This study was funded by a diversity supplement and is part of a larger intervention project funded by the National Institute on Alcohol Abuse and Alcoholism (led by Dr. Elizabeth D'Amico).


Journal Reference:

  1. Shih, R. A., Miles, J. N. V., Tucker, J. S., Zhou, A. J., & D'Amico, E. J. Racial/Ethnic Differences in Adolescent Substance Use: Mediation by Individual, Family, and School Factors. Journal of Studies on Alcohol and Drugs, 2010; 71 (5), 640-651

Smoked medical cannabis may be beneficial as treatment for chronic neuropathic pain, study suggests

The medicinal use of cannabis has been debated by clinicians, researchers, legislators and the public at large for many years as an alternative to standard pharmaceutical treatments for pain, which may not always be effective and may have unwanted side effects. A new study by McGill University Health Centre (MUHC) and McGill University researchers provides evidence that cannabis may offer relief to patients suffering from chronic neuropathic pain.

The results of the groundbreaking study are published in the latest issue of the Canadian Medical Association Journal.

"This is the first trial to be conducted where patients have been allowed to smoke cannabis at home and to monitor their responses, daily," says Dr. Mark Ware, lead author of the study, who is also Director of Clinical Research at the Alan Edwards Pain Management Unit at the MUHC and an assistant professor of anesthesia in McGill University's Faculty of Medicine, and neuroscience researcher at the Research Institute of the MUHC.

In this study, low doses (25mg) of inhaled cannabis containing approximately 10% THC (the active ingredient in cannabis), smoked as a single inhalation using a pipe three times daily over a period of five days, offered modest pain reduction in patients suffering from chronic neuropathic pain (pain associated with nerve injury) within the first few days. The results also suggest that cannabis improved moods and helped patients sleep better. The effects were less pronounced in cannabis strains containing less than 10% THC.

"The patients we followed suffered from pain caused by injuries to the nervous system from post-traumatic (e.g. traffic accidents) or post-surgical (e.g. cut nerves) events, and which was not controlled using standard therapies" explains Dr. Ware. "This kind of pain occurs more frequently than many people recognize, and there are few effective treatments available. For these patients, medical cannabis is sometimes seen as their last hope."

"This study marks an important step forward because it demonstrates the analgesic effects of cannabis at a low dose over a shot period of time for patients suffering from chronic neuropathic pain," adds Dr. Ware. The study used herbal cannabis from Prairie Plant Systems (under contract to Health Canada to provide cannabis for research and medical purposes), and a 0% THC 'placebo' cannabis from the USA.

However, larger-scale studies with a longer time frame and higher doses of THC are needed to further evaluate the efficacy and long-term safety of medical cannabis. "Our challenge as researchers is to continue to conduct rigorous clinical studies on the medical use of cannabis with strict attention to details such as quality and dosage," says Dr. Ware. "This will allow us to move the debate forward by providing reliable scientific clinical data."


Journal Reference:

  1. Mark A. Ware MBBS, Tongtong Wang PhD, Stan Shapiro PhD, Ann Robinson RN, Thierry Ducruet MSc, Thao Huynh MD, Ann Gamsa PhD, Gary J. Bennett PhD, Jean-Paul Collet MD PhD. Smoked cannabis for chronic neuropathic pain. Canadian Medical Association Journal, 2010; DOI: 10.1503/cmaj.091414

Painkilling system in brain: Too much of a good thing?

Repeatedly boosting brain levels of one natural painkiller soon shuts down the brain cell receptors that respond to it, so that the painkilling effect is lost, according to a surprising new study led by Scripps Research Institute and Virginia Commonwealth University scientists. The study has important implications for drug development.

The natural painkiller, 2-AG, is one of the two major "endocannabinoid" neurotransmitters. The other, anandamide, can be kept at high levels in the brain without losing its therapeutic effects, and researchers had hoped that the same would be true for 2-AG.

"One implication is that maximally elevating 2-AG levels in the brain might not provide a straightforward path to new pain drugs," says Benjamin F. Cravatt III, PhD, professor and chair of the Department of Chemical Physiology and member of the Skaggs Institute for Chemical Biology at Scripps Research in La Jolla, California, who led the study with Aron Lichtman, PhD, a professor of pharmacology and toxicology at Virginia Commonwealth University in Richmond, Virginia. "But we remain optimistic that more modest elevations in 2-AG could produce sustained pain relief. Perhaps more importantly, on a basic science level, we've been able to tease apart a key difference between the two major endocannabinoid signaling pathways, since one can maximally elevate anandamide without observing tolerance."

The report appears in the August 22, 2010 issue of Nature Neuroscience.

A Better Chill Pill

Like the opioid system, the endocannabinoid system was discovered as a result of humans identifying a plant — in this case marijuana (cannabis sativa) — that artificially boosts its activity. Marijuana's main active ingredient, THC, typically reduces pain and anxiety. Researchers have sought to develop drugs that reproduce such therapeutic effects while leaving out THC's unwanted side effects — which include memory impairment, locomotor dysfunction, and possibly addiction.

Cannabinoid research received a boost in 1990 with the description of the main cannabinoid receptor in the brain, CB1, and a few years later with the discoveries of the body's own (endo-) cannabinoids, anandamide and 2-AG, which exert most of their effects by binding to CB1. Cannabinoid receptors are now known to be widely distributed in the brain, and when activated by anandamide or 2-AG, tend to calm the activity of the neurons where they reside. However, researchers so far have been unable to develop artificial cannabinoids that bind to CB1 without producing unwelcome THC-like side effects.

An alternative strategy has been to boost levels of the body's own cannabinoids by inhibiting the enzymes that normally break them down. And so far this has worked for anandamide. Inhibitors of its breakdown enzyme, fatty acid amide hydrolase (FAAH), have been shown to boost anandamide levels and reduce pain and inflammation without adverse side effects in animal tests and early clinical trials.

A similar strategy for boosting 2-AG may be promising, too, especially since 2-AG levels in the brain are naturally higher than anandamide's. Two years ago, the Cravatt and Lichtman laboratories jointly reported the development of an inhibitor of 2-AG's breakdown enzyme, monoacylglycerol lipase (MAGL). When administered to mice, it boosted their brain levels of 2-AG on average by a factor of eight, and produced a pain-killing effect comparable to that of FAAH inhibitors.

Diminishing Returns

Now the two labs report that 2-AG's pain-killing effect disappears after six days of treatment. "When you continually stimulate the endocannabinoid system by maximally raising 2-AG levels, you effectively desensitize the system," says Cravatt.

In one experiment, an injection of the MAGL inhibitor into mice showed evidence of pain relief on standard tests, but after six consecutive daily injections the drug could no longer achieve this effect. These chronically treated mice also lost much of their sensitivity to THC and to a synthetic CB1-binding compound, and showed a classic sign of drug dependency�when abruptly withdrawn from 2-AG's influence by having their CB1 receptors blocked, they developed paw flutters — a murine version of the shakes.

"When we investigated at the molecular level, we found that the number of CB1 receptors in the mouse brains had been reduced," says Jacqueline Blankman, a graduate student at the Scripps Research Kellogg School of Science and Technology who was co-first-author on the paper with Joel Schlosburg of the Lichtman lab. This receptor "downregulation" occurred in some brain areas but not others

To confirm this effect, the researchers utilized another experimental mouse model where the gene for MAGL was inactivated. This lifelong genetic disruption of MAGL also resulted in high 2-AG levels as well as a reduced and desensitized CB1 system.

"Because we're seeing downregulation of the whole cannabinoid system and tolerance to the anti-pain effects, it does raise some concern about whether MAGL would be a suitable pain target," says Blankman.

"If you are going to inhibit MAGL, you probably wouldn't want to produce a complete inactivation of the enzyme," Cravatt adds.

By contrast with the 2-AG experiments, chronically boosting anandamide had none of these effects on the CB1 system. Cravatt doesn't yet know why these two molecules have such different impacts when delivered chronically. He notes, however, that anandamide may be produced selectively under stress conditions, and perhaps for that reason is less likely to trigger a brain-wide CB1 downregulation.

"The question of why anandamide and 2-AG have such different effects when given chronically is certainly going to be motivating us from now on," says Cravatt. "But already with this finding and the development of these models we've taken a significant step forward in understanding and being able to manipulate this important neurotransmitter system."

In addition to Cravatt, Lichtman, Blankman, and Schlosburg, co-authors of the article "Chronic monoacylglycerol lipase blockade causes functional antagonism of the endocannabinoid system" include Jonathan Z. Long, Daniel K. Nomura, and Elizabeth A. Thomas of Scripps Research; Steven G. Kinsey, Peter T. Nguyen, Divya Ramesh, Lamont Booker, James J. Burston, Dana E Selley and Laura J. Sim-Selley of Virginia Commonwealth University; and Bin Pan and Qing-song Liu of the Medical College of Wisconsin in Milwaukee, Wisconsin.

This study was supported by the National Institutes of Health.


Journal Reference:

  1. Joel E Schlosburg, Jacqueline L Blankman, Jonathan Z Long, Daniel K Nomura, Bin Pan, Steven G Kinsey, Peter T Nguyen, Divya Ramesh, Lamont Booker, James J Burston, Elizabeth A Thomas, Dana E Selley, Laura J Sim-Selley, Qing-song Liu, Aron H Lichtman, Benjamin F Cravatt. Chronic monoacylglycerol lipase blockade causes functional antagonism of the endocannabinoid system. Nature Neuroscience, 2010; DOI: 10.1038/nn.2616

Sleep deprivation influences drug use in teens' social networks, study finds

Recent studies have shown that behaviors such as happiness, obesity, smoking and altruism are "contagious" within adult social networks. In other words, your behavior not only influences your friends, but also their friends and so on. Researchers at the University of California, San Diego and Harvard University have taken this a step farther and found that the spread of one behavior in social networks — in this case, poor sleep patterns — influences the spread of another behavior, adolescent drug use.

The study, led by Sara C. Mednick, PhD, assistant professor of psychiatry at the University of California, San Diego School of Medicine and the VA San Diego Healthcare System, will be published March 19 in PLoS ONE.

"This is our first investigation of the spread of illegal drug use in social networks," said Mednick. "We believe it is also the first study in any age population on the spread of sleep behaviors through social networks."

Using social network data from the National Longitudinal Study of Adolescent Health, Mednick and her colleagues James H. Fowler, UCSD Department of Political Science and Nicholas A. Christakis, Harvard Medical School, mapped the social networks of 8,349 adolescents in grades 7 through 12. They found clusters of poor sleep behavior and marijuana use that extended up to four degrees of separation (to one's friends' friends' friends' friends) in the social network.

Another novel network effect that they discovered was that teens who are at the center of the network are at greater risk of poor sleep, which in turn means they are more likely to use marijuana — putting them at the crossroads of two behaviors increases a teenager's vulnerability.

Contrary to the general assumption that drug use has a negative effect on sleep, the researchers also found that sleep loss is likely to drive adolescents to use drugs — the less they sleep the more likely their friends are to sleep poorly and use marijuana.

"Our behaviors are connected to each other and we need to start thinking about how one behavior affects our lives on many levels," said Mednick. "Therefore, when parents, schools and law enforcement want to look for ways to influence one outcome, such as drug use, our research suggests that targeting another behavior, like sleep, may have a positive influence. They should be promoting healthy sleep habits that eliminate behaviors which interfere with sleep: take the TV out of the child's bedroom, limit computer and phone usage to daytime and early evening hours, and promote napping."

The research was funded by the National Institute of Mental Health, National Institute on Aging and National Institute of Child Health and Human Development.


Journal Reference:

  1. Sara C. Mednick, Nicholas A. Christakis, James H. Fowler, Kenji Hashimoto. The Spread of Sleep Loss Influences Drug Use in Adolescent Social Networks. PLoS ONE, 2010; 5 (3): e9775 DOI: 10.1371/journal.pone.0009775

Toxicologist warning to parents: Look for signs of K2 — 'fake marijuana'

— In the last month, Anthony Scalzo, M.D., professor of toxicology at Saint Louis University, has seen nearly 30 cases involving teenagers who were experiencing hallucinations, severe agitation, elevated heart rate and blood pressure, vomiting and, in some cases, tremors and seizures. All of these teens had smoked a dangerous, yet legal substance known as K2 or "fake weed."

According to Scalzo, K2, an unregulated mixture of dried herbs, is growing in popularity because it is legal, purported to give a high similar to marijuana and believed to be natural and therefore safe.

"K2 may be a mixture of herbal and spice plant products, but it is sprayed with a potent psychotropic drug and likely contaminated with an unknown toxic substance that is causing many adverse effects. These toxic chemicals are neither natural nor safe," said Scalzo, who also directs the Missouri Regional Poison Control Center at SSM Cardinal Glennon Children's Medical Center.

What makes K2 so dangerous? Further testing is needed, but Scalzo says the symptoms, such as fast heart beat, dangerously elevated blood pressure, pale skin and vomiting suggest that K2 is affecting the cardiovascular system of users. It also is believed to affect the central nervous system, causing severe, potentially life-threatening hallucinations and, in some cases, seizures.

While JWH 018, a synthetic man-made drug, similar to cannabis, may be responsible for the hallucinations, Scalzo suspects that there is another unknown toxic chemical being sprayed on K2.

K2, also known as "spice," has been sold since 2006 as incense or potpourri. It sells for approximately $30 to $40 per three gram bag, which is comparable in cost to marijuana, and is available over the Internet.

"K2 use is not limited to the Midwest; reports of its use are cropping up all over the country. I think K2 is likely a bigger problem than we're aware of at this time," Scalzo said.

Legislators in Missouri currently are considering a proposed ban of K2, which Scalzo supports. In the meantime, he says that parents should be on the lookout for warning signs such as agitation, pale appearance, anxiety or confusion due to hallucinations.

"Look for dried herb residues lying around your kids' room. Chances are they are not using potpourri to make their rooms smell better or oregano to put on their pizza," Scalzo said.

Long-time cannabis use associated with psychosis

Young adults who have used cannabis or marijuana for a longer period of time appear more likely to have hallucinations or delusions or to meet criteria for psychosis, according to a report posted online that will appear in the May print issue of Archives of General Psychiatry, one of the JAMA/Archives journals.

Previous studies have identified an association between cannabis use and psychosis, according to background information in the article. However, concerns remain that this research has not adequately accounted for confounding variables.

John McGrath, M.D., Ph.D., F.R.A.N.Z.C.P., of the Queensland Brain Institute, University of Queensland, Australia, and colleagues studied 3,801 young adults born between 1981 and 1984. At a 21-year follow-up, when participants were an average age of 20.1, they were asked about cannabis use in recent years and assessed using several measures of psychotic outcomes (including a diagnostic interview, an inventory of delusions and items identifying the presence of hallucinations).

At the 21-year follow-up, 17.7 percent reported using cannabis for three or fewer years, 16.2 percent for four to five years and 14.3 percent for six or more years. Overall, 65 study participants received a diagnosis of "non-affective psychosis," such as schizophrenia, and 233 had at least one positive item for hallucination on the diagnostic interview.

Among all the participants, a longer duration since the first time they used cannabis was associated with multiple psychosis-related outcomes. "Compared with those who had never used cannabis, young adults who had six or more years since first use of cannabis (i.e., who commenced use when around 15 years or younger) were twice as likely to develop a non-affective psychosis and were four times as likely to have high scores on the Peters et al Delusions Inventory [a measure of delusion]," the authors write. "There was a 'dose-response' relationship between the variables of interest: the longer the duration since first cannabis use, the higher the risk of psychosis-related outcomes."

In addition, the researchers assessed the association between cannabis use and psychotic symptoms among a subgroup of 228 sibling pairs. The association persisted in this subgroup, "thus reducing the likelihood that the association was due to unmeasured shared genetic and/or environmental influences," the authors continue.

"The nature of the relationship between psychosis and cannabis use is by no means simple," they write. Individuals who had experienced hallucinations early in life were more likely to have used cannabis longer and to use it more frequently. "This demonstrates the complexity of the relationship: those individuals who were vulnerable to psychosis (i.e., those who had isolated psychotic symptoms) were more likely to commence cannabis use, which could then subsequently contribute to an increased risk of conversion to a non-affective psychotic disorder."

The findings should encourage further research to elucidate the mechanisms underlying the relationship between psychosis and cannabis use, the authors conclude.

This work was funded by the National Health and Medical Research Council of Australia. Co-author Dr. Alati is funded by a National Health and Medical Research Council Career Development Award in Population Health.


Journal Reference:

  1. John McGrath; Joy Welham; James Scott; Daniel Varghese; Louisa Degenhardt; Mohammad Reza Hayatbakhsh; Rosa Alati; Gail M. Williams; William Bor; Jake M. Najman. Association Between Cannabis Use and Psychosis-Related Outcomes Using Sibling Pair Analysis in a Cohort of Young Adults. Arch Gen Psychiatry, 2010; 0 (2010): 2010. 6 [link]