Something for the pain
Do Medical Marijuana Laws Reduce Addictions and Deaths Related to Pain Killers?
David Powell, Rosalie Liccardo Pacula & Mireille Jacobson
NBER Working Paper, July 2015
Abstract:
Many medical marijuana patients report using marijuana to alleviate chronic pain from musculoskeletal problems and other sources. If marijuana is used as a substitute for powerful and addictive pain relievers in medical marijuana states, a potential overlooked positive impact of medical marijuana laws may be a reduction in harms associated with opioid pain relievers, a far more addictive and potentially deadly substance. To assess this issue, we study the impact of medical marijuana laws on problematic opioid use. We use two measures of problematic use: treatment admissions for opioid pain reliever addiction from the Treatment Episode Data Set (TEDS) and state-level opioid overdose deaths in the National Vital Statistics System (NVSS). Using both standard differences-in-differences models as well as synthetic control models, we find that states permitting medical marijuana dispensaries experience a relative decrease in both opioid addictions and opioid overdose deaths compared to states that do not. We find no impact of medical marijuana laws more broadly; the mitigating effect of medical marijuana laws is specific to states that permit dispensaries. We evaluate potential mechanisms. Our findings suggest that providing broader access to medical marijuana may have the potential benefit of reducing abuse of highly addictive painkillers.
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Sarah Mars et al.
Social Science & Medicine, September 2015, Pages 44–53
Abstract:
Heroin overdose, more accurately termed ‘heroin-related overdose’ due to the frequent involvement of other drugs, is the leading cause of mortality among regular heroin users. Heroin injectors are at greater risk of hospital admission for heroin-related overdose (HOD) in the eastern United States where Colombian-sourced powder heroin is sold than in the western US where black ‘tar’ heroin predominates. This paper examines under-researched influences on HOD, both fatal and non-fatal, using data from a qualitative study of injecting drug users of black tar heroin in San Francisco and powder heroin in Philadelphia. Data were collected through in-depth, semi-structured interviews carried out in 2012 that were conducted against a background of longer-term participant-observation, ethnographic studies of drug users and dealers in Philadelphia (2007–12) and of users in San Francisco (1994–2007, 2012). Our findings suggest three types of previously unconsidered influences on overdose risk, that arise both from structural socio-economic factors and from the physical properties of the heroin source-types: 1) retail market structure including information flow between users; 2) marketing techniques such as branding, free samples and pricing and 3) differences in the physical characteristics of the two major heroin source forms and how they affect injecting techniques and vascular health. Although chosen for their contrasting source-forms, we found that the two cities have contrasting dominant models of drug retailing: San Francisco respondents tended to buy through private dealers and Philadelphia respondents frequented an open-air street market where heroin is branded and free samples are distributed, although each city included both types of drug sales. These market structures and marketing techniques shape the availability of information regarding heroin potency and its dissemination among users who tend to seek out the strongest heroin available on a given day. The physical characteristics of these two source-types, the way they are prepared for injecting and their effects on vein health also differ markedly. The purpose of this paper is to examine some of the unexplored factors that may lead to heroin-related overdose in the United States and to generate hypotheses for further study.
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Stephanie Lanza et al.
Journal of Adolescent Health, August 2015, Pages 198–204
Purpose: The purpose of this study was to describe historical trends in rates of recent substance use and associations between marijuana and other substances, among U.S. high school seniors by race and gender.
Methods: Data from Monitoring the Future (1976–2013; N = 599,109) were used to estimate historical trends in alcohol use, heavy episodic drinking (HED), cigarette use, and marijuana use. We used time-varying effect models to flexibly estimate changes in associations of substance use behaviors.
Results: Past-month marijuana use rates peaked in the 1970s, declined through 1990, then rose again to reach levels of use of more than 20% for both black and white participants. Recent years show increasing disparities across groups such that males, and in particular black youth, are on a trajectory toward higher use. This rise in marijuana use is particularly concerning among black youth, with rates far exceeding those for cigarette use and HED. The association of marijuana use with both cigarette use and HED is particularly high in recent years among black adolescents.
Conclusions: Substance use recently declined among high school seniors, except for marijuana use, particularly among black youth. The increasing association between marijuana and other substances among black adolescents suggests future amplification in critical health disparities.
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Eye color: A potential indicator of alcohol dependence risk in European Americans
Arvis Sulovari et al.
American Journal of Medical Genetics Part B: Neuropsychiatric Genetics, July 2015, Pages 347–353
Abstract:
In archival samples of European-ancestry subjects, light-eyed individuals have been found to consume more alcohol than dark-eyed individuals. No published population-based studies have directly tested the association between alcohol dependence (AD) and eye color. We hypothesized that light-eyed individuals have a higher prevalence of AD than dark-eyed individuals. A mixture model was used to select a homogeneous sample of 1,263 European-Americans and control for population stratification. After quality control, we conducted an association study using logistic regression, adjusting for confounders (age, sex, and genetic ancestry). We found evidence of association between AD and blue eye color (P = 0.0005 and odds ratio = 1.83 (1.31–2.57)), supporting light eye color as a risk factor relative to brown eye color. Network-based analyses revealed a statistically significant (P = 0.02) number of genetic interactions between eye color genes and AD-associated genes. We found evidence of linkage disequilibrium between an AD-associated GABA receptor gene cluster, GABRB3/GABRG3, and eye color genes, OCA2/HERC2, as well as between AD-associated GRM5 and pigmentation-associated TYR. Our population-phenotype, network, and linkage disequilibrium analyses support association between blue eye color and AD. Although we controlled for stratification we cannot exclude underlying occult stratification as a contributor to this observation. Although replication is needed, our findings suggest that eye pigmentation information may be useful in research on AD. Further characterization of this association may unravel new AD etiological factors.
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The role of decision-making in cannabis-related problems among young adults
Raul Gonzalez et al.
Drug and Alcohol Dependence, September 2015, Pages 214–221
Background: Deficits in decision-making and episodic memory are often reported among heavy cannabis users, yet little is known on how they influence negative consequences from cannabis use. Individual differences in decision-making may explain, in part, why some individuals experience significant problems from their cannabis use whereas others do not. We hypothesized that poor decision-making would moderate relationships between amount of cannabis use and problems from cannabis use whereas episodic memory performance would not.
Method: Young adult cannabis users (n = 52) with cannabis as their drug of choice and with minimal comorbidities completed semi-structured interviews, self-report questionnaires, and measures of neurocognitive functioning, with decision-making accessed via the Iowa Gambling Task (IGT), episodic memory via the Hopkins Verbal Learning Test – Revised (HVLT) and problems from cannabis use with the Marijuana Problems Scale.
Results: Strong relationships were observed between amount of cannabis use (lifetime, 12-month, and 30-day) and problems reported from use, but only among participants with low (impaired) decision-making (R2 = .39 to .51; p < .01). No significant relationships were observed among those with better (low average to high average) decision-making performance (p > .05). In contrast, episodic memory performance was not a significant moderator of the relationship between amount of cannabis use and cannabis problems (p > .05).
Conclusions: Cannabis users with poor decision-making may be at greater risk for experiencing significant negative consequences from their cannabis use. Our results lend further support to emerging evidence of decision-making as a risk factor for addiction and extend these findings to cannabis users.
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Bryan Lee Miller et al.
American Journal of Criminal Justice, September 2015, Pages 523-541
Abstract:
Recent social and legal responses to novel psychoactive drugs (NPDs) have been attributed to media panics rather than these substance’s actual harms. NPDs, including botanical substances new to Western markets such as Salvia divinorum, newly synthesized analogues such as synthetic cannabinoids and “bath salts,” and new ways of administering drugs, such as combining prescription cough syrup with soda (“purple drank”) have been the target of various forms of legislation at the state and/or federal level. We systematically examine print media coverage of NPDs in the U. S. between 2005 and 2013 to determine whether media attention was temporally associated with legislative change. Results indicate that each drug had a brief window during which it was the focus of sensationalistic reporting. In addition, federal legislation banning synthetic cannabinoids and “bath salts” appear to be closely linked to media reporting as spikes in coverage both preceded and followed the bans.
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Effects of wages on smoking decisions of current and past smokers
Juan Du & Paul Leigh
Annals of Epidemiology, August 2015, Pages 575–582.e1
Purpose: We used longitudinal data and instrumental variables (IVs) in a prospective design to test for the causal effects of wages on smoking prevalence among current and past smokers.
Methods: Nationally representative U.S. data were drawn from the 1999–2009 waves of the Panel Study of Income Dynamics. Our overall sample was restricted to full time employed persons, aged 21–65 years. We excluded part time workers and youths because smoking and wage correlations would be complicated by labor supply decisions. We excluded adult never smokers because people rarely begin smoking after the age of 20 years. IVs were created with state-level minimum wages and unionization rates. We analyzed subsamples of men, women, the less educated, the more educated, quitters, and backsliders. Validity and strength of instruments within the IV analysis were conducted with the Sargan-Hansen J statistic and F tests.
Results: We found some evidence that low wages lead to more smoking in the overall sample and substantial evidence for men, persons with high school educations or less (<13 years of schooling), and quitters. Results indicated that 10% increases in wages lead to 5.5 and 4.6 percentage point decreases in smoking for men and the less educated; they also increased the average chance of quitting among base-year smokers from 17.0% to 20.4%. Statistical tests suggested that IVs were strong and valid in most samples. Subjects' other family income, including spouses' wages, was entered as a control variable.
Conclusions: Increases in an individual's wages, independent of other income, decreased the prevalence of smoking among current and past smokers.
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Identifying Demand Responses to Illegal Drug Supply Interdictions
Scott Cunningham & Keith Finlay
Health Economics, forthcoming
Abstract:
Successful supply-side interdictions into illegal drug markets are predicated on the responsiveness of drug prices to enforcement and the price elasticity of demand for addictive drugs. We present causal estimates that targeted interventions aimed at methamphetamine input markets (‘precursor control’) can temporarily increase retail street prices, but methamphetamine consumption is weakly responsive to higher drug prices. After the supply interventions, purity-adjusted prices increased then quickly returned to pre-treatment levels within 6–12 months, demonstrating the short-term effects of precursor control. The price elasticity of methamphetamine demand is −0.13 to −0.21 for self-admitted drug treatment admissions and between −0.24 and −0.28 for hospital inpatient admissions. We find some evidence of a positive cross-price effect for cocaine, but we do not find robust evidence that increases in methamphetamine prices increased heroin, alcohol, or marijuana drug use. This study can inform policy discussions regarding other synthesized drugs, including illicit use of pharmaceuticals.
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Type of army service and decision to engage in risky behavior among young people in Israel
Sharon Garyn-Tal & Shosh Shahrabani
Judgment and Decision Making, July 2015, Pages 342–354
Abstract:
Previous studies have examined the impact of military service on the decision to engage in risky behavior. Yet most of these studies focused on voluntary recruits, did not distinguish between legal and illegal risky activities and did not compare combat and non-combat soldiers during and after service according to gender. The current study is unique because of the nature of Israeli compulsory army service. It examines the relationship between type of army service and five legal and illegal risky behaviors for three groups: non-combat, combat without fighting experience, and combat with fighting experience. We also examine differences in the propensity for risky behavior between men, most of whom are assigned to combat units due to the army’s needs, and women, who serve in combat units on a voluntary basis only. A questionnaire survey was randomly distributed at train stations and central bus stations in Israel among 413 soldiers and ex-soldiers between the ages of 18-30. The predictor variables include type of service or battle experience, the Evaluation of Risks scale and sociodemographic characteristics. In general, we found that high percentages of young people engage in risky behavior, especially illegal behavior. The results indicate that fighting experience is significantly and positively correlated with the consumption of illegal substances for currently serving men soldiers (but not for women) and this effect is mitigated after discharge from the army. Importantly, the use of illegal substances is not a result of the individual’s preferences for engaging in various risky behaviors. Thus, our results suggest that the effect of the increased propensity toward risky behavior following the experience of fighting overrides the combat unit’s discipline for men when it comes to the consumption of illegal substances. In addition, our findings indicate that serving in a combat unit as opposed to a non-combat unit affects the tendency of women ex-combat soldiers to travel to risky destinations, though this is probably related to their original higher risk attitude, since women must volunteer for combat units.
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Kelly Rulison et al.
Journal of Adolescent Health, forthcoming
Purpose: We tested whether effects of the Strengthening Families Program for Youth 10–14 (SFP10-14) diffused from intervention participants to their friends. We also tested which program effects on participants accounted for diffusion.
Methods: Data are from 5,449 students (51% female; mean initial age = 12.3 years) in the PROmoting School-community-university Partnerships to Enhance Resilience community intervention trial (2001–2006) who did not participate in SFP10-14 (i.e., nonparticipants). At each of five waves, students identified up to seven friends and self-reported past month drunkenness and cigarette use, substance use attitudes, parenting practices, and unsupervised time spent with friends. We computed two measures of indirect exposure to SFP10-14: total number of SFP-attending friends at each wave and cumulative proportion of SFP-attending friends averaged across the current and all previous post-intervention waves.
Results: Three years post-intervention, the odds of getting drunk (odds ratio = 1.4) and using cigarettes (odds ratio = 2.7) were higher among nonparticipants with zero SFP-attending friends compared with nonparticipants with three or more SFP-attending friends. Multilevel analyses also provided evidence of diffusion: nonparticipants with a higher cumulative proportion of SFP-attending friends at a given wave were less likely than their peers to use drugs at that wave. Effects from SFP10-14 primarily diffused through friendship networks by reducing the amount of unstructured socializing (unsupervised time that nonparticipants spent with friends), changing friends' substance use attitudes, and then changing nonparticipants' own substance use attitudes.
Conclusions: Program developers should consider and test how interventions may facilitate diffusion to extend program reach and promote program sustainability.
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The Long-Term Consequences of Vietnam-Era Conscription and Genotype on Smoking Behavior and Health
Lauren Schmitz & Dalton Conley
NBER Working Paper, July 2015
Abstract:
Research is needed to understand the extent to which environmental factors mediate links between genetic risk and the development of smoking behaviors. The Vietnam-era draft lottery offers a unique opportunity to investigate whether genetic susceptibility to smoking is influenced by risky environments in young adulthood. Access to free or reduced-price cigarettes coupled with the stress of military life meant conscripts were exposed to a large, exogenous shock to smoking behavior at a young age. Using data from the Health and Retirement Study (HRS), we interact a genetic risk score for smoking initiation with instrumented veteran status in an instrumental variables (IV) framework to test for genetic moderation (i.e. heterogeneous treatment effects) of veteran status on smoking behavior and smoking-related morbidities. We find evidence that veterans with a high genetic predisposition for smoking were more likely to become regular smokers, smoke heavily, and are at a higher risk of being diagnosed with cancer or hypertension at older ages. Smoking behavior was significantly attenuated for high-risk veterans who attended college after the war, indicating post-service schooling gains from veterans’ use of the GI Bill may have reduced tobacco consumption in adulthood.
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Prescription Drug Misuse and Sexual Behavior Among Young Adults
Brooke Wells et al.
Journal of Sex Research, Summer 2015, Pages 659-668
Abstract:
Though research indicates a complex link between substance use and sexual risk behavior, there is limited research on the association between sexual risk behavior and prescription drug misuse. In light of alarming increases in prescription drug misuse and the role of demographic characteristics in sexual risk behavior and outcomes, the current study examined demographic differences (gender, sexual identity, age, relationship status, parental class background, and race/ethnicity) in sexual risk behavior, sexual behavior under the influence of prescription drugs, and sexual risk behavior under the influence of prescription drugs in a sample of 402 young adults (ages 18 to 29) who misused prescription drugs. Nearly half of the sexually active young adult prescription drug misusers in this sample reported recent sex under the influence of prescription drugs; more than three-quarters reported recent sex without a condom; and more than one-third reported recent sex without a condom after using prescription drugs. Zero-inflated Poisson regression models indicated that White race, younger age, higher parental class, and being a heterosexual man were all associated with sexual risk behavior, sex under the influence of prescription drugs, and sexual risk under the influence of prescription drugs. Findings have implications for the targeting of prevention and intervention efforts.
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Effects of a 2009 Illinois Alcohol Tax Increase on Fatal Motor Vehicle Crashes
Alexander Wagenaar, Melvin Livingston & Stephanie Staras
American Journal of Public Health, September 2015, Pages 1880-1885
Objectives: We examined the effects of a 2009 increase in alcohol taxes in Illinois on alcohol-related fatal motor vehicle crashes.
Methods: We used an interrupted time-series design, with intrastate and cross-state comparisons and measurement derived from driver alcohol test results, for 104 months before and 28 months after enactment. Our analyses used autoregressive moving average and generalized linear mixed Poisson models. We examined both population-wide effects and stratifications by alcohol level, age, gender, and race.
Results: Fatal alcohol-related motor vehicle crashes declined 9.9 per month after the tax increase, a 26% reduction. The effect was similar for alcohol-impaired drivers with positive alcohol levels lower than 0.15 grams per deciliter (−22%) and drivers with very high alcohol levels of 0.15 or more (−25%). Drivers younger than 30 years showed larger declines (−37%) than those aged 30 years and older (−23%), but gender and race stratifications did not significantly differ.
Conclusions: Increases in alcohol excise taxes, such as the 2009 Illinois act, could save thousands of lives yearly across the United States as part of a comprehensive strategy to reduce alcohol-impaired driving.
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A Randomized Controlled Trial of a Behavioral Economic Intervention for Alcohol and Marijuana Use
Ali Yurasek, Ashley Dennhardt & James Murphy
Experimental and Clinical Psychopharmacology, forthcoming
Abstract:
A recent study demonstrated that a single 50-min supplemental session that targeted the behavioral economic mechanisms of substance-free reinforcement and delayed reward discounting (Substance-Free Activity Session: SFAS) enhanced the efficacy of a standard alcohol brief motivational intervention (BMI) for college drinkers. The purpose of the current study was to conduct a randomized controlled trial intended to replicate and extend the aforementioned study by focusing on both drug and alcohol misuse and reducing session length in order to enhance dissemination potential. Participants were 97 college students (58.8% women; 59.8% White/Caucasian, and 30.9% African American; M age = 20.01, SD = 2.23) who reported at least 1 heavy drinking episode in the past month (M = 4.01 episodes). Most participants (62%) reported recent marijuana use (M = 12.22 days of past-month use). After completing a baseline assessment and an individual 30-min alcohol-focused BMI, participants were randomized to either the 30-min SFAS session or an education control session. A series of mixed model intent-to-treat analyses revealed that both groups reported drinking reductions and that participants in the BMI + SFAS group reported fewer days using marijuana at the 6-month follow-up. These results do not support the incremental efficacy of the briefer SFAS for reducing drinking but suggest that it may improve marijuana outcomes. Future research is needed to identify the ideal length and timing of the SFAS supplement to BMIs.