Substitution and complementarity in the face of alcohol-specific policy interventions

Effects of a large-scale alcohol ban on population-level alcohol intake, weight, blood pressure, blood glucose, and domestic violence in India: a quasi-experimental population-based study

Background

Globally, alcohol consumption is a leading risk factor for deaths and disability and a causal factor in over 200 diseases, injuries, and health conditions. In April 2016, the manufacture, transport, sale, and consumption of alcohol was banned in Bihar, a populous Indian state. We sought to estimate the impacts of this ban on health outcomes and domestic violence.

Methods

Data from the Indian National Family Health Surveys (2005-06, 2015-16, 2019-21), Annual Health Survey (2013), and District Level Household Survey (2012), were used to conduct difference-in-differences (DID) analysis, comparing Bihar (n = 10,733 men, n = 88,188 women) and neighbouring states (n = 38,674 men, n = 284,820 women) before and after the ban. Outcomes included frequent (daily or weekly) alcohol consumption, underweight, obesity, hypertension, diabetes, and intimate partner violence. A triple difference model adding male-female interaction to the DID model was also estimated. Attributable averted cases were calculated to estimate the impact of the ban.

Findings

Across all models, the ban led to reduced frequent alcohol consumption (DID: -7.1 percentage points (pp) (95% CI -9.6pp, -4.6pp), lower overweight/obesity (-5.6pp (-8.9, -2.2) among males, and reduced experiences of emotional (-4.8pp (-8.2pp, -1.4pp) and sexual (-5.5pp (-8.7pp, -2.3pp) violence among females. The ban prevented approximately 2.4 million cases of daily/weekly alcohol consumption and 1.8 million cases of overweight/obesity among males, and 2.1 million cases of intimate partner violence among females.

Interpretation

Strict alcohol regulation policies may yield significant population level health benefits for frequent drinkers and many victims of intimate partner violence.

Funding

No funding was received for this work.

Substitute Behaviors following Residential Substance Use Treatment in the Western Cape, South Africa

The dynamics of substitute behaviors and associated factors remain poorly understood globally, and particularly in low- and middle-income contexts. This prospective study describes the prevalence and types of substitute behaviors as well as predictors, correlates, and motivations associated with substitution in persons (n = 137) admitted to residential substance use treatment in the Western Cape province of South Africa. The brief assessment of recovery capital, overall life satisfaction scale, and an adapted version of the addiction matrix self-report measure were completed during and post-treatment. Results indicate that substitutes were employed consciously for anticipated appetitive effects, for time-spending, (re)connecting with others, and enjoyment. At follow-up, 36% of service users had substituted their primary substance(s) with another substance or behavior; 23% had relapsed and 40% had maintained abstinence. While some service users may be especially vulnerable to developing substitute behaviors, targeted prevention and intervention efforts can reduce this risk.

Intended and unintended consequences of the implementation of minimum unit pricing of alcohol in Scotland: a natural experiment

Background

Scotland was the first country to implement minimum unit pricing for alcohol nationally. Minimum unit pricing aims to reduce alcohol-related harms and to narrow health inequalities. Minimum unit pricing sets a minimum retail price based on alcohol content, targeting products preferentially consumed by high-risk drinkers. This study comprised three components.

Objectives

This study comprised three components assessing alcohol consumption and alcohol-related attendances in emergency departments, investigating potential unintended effects of minimum unit pricing on alcohol source and drug use, and exploring changes in public attitudes, experiences and norms towards minimum unit pricing and alcohol use.

Design

We conducted a natural experiment study using repeated cross-sectional surveys comparing Scotland (intervention) and North England (control) areas. This involved comparing changes in Scotland following the introduction of minimum unit pricing with changes seen in the north of England over the same period. Difference-in-difference analyses compared intervention and control areas. Focus groups with young people and heavy drinkers, and interviews with professional stakeholders before and after minimum unit pricing implementation in Scotland allowed exploration of attitudes, experiences and behaviours, stakeholder perceptions and potential mechanisms of effect.

Setting

Four emergency departments in Scotland and North England (component 1), six sexual health clinics in Scotland and North England (component 2), and focus groups and interviews in Scotland (component 3).

Participants

Research nurses interviewed 23,455 adults in emergency departments, and 15,218 participants self-completed questionnaires in sexual health clinics. We interviewed 30 stakeholders and 105 individuals participated in focus groups.

Intervention

Minimum unit pricing sets a minimum retail price based on alcohol content, targeting products preferentially consumed by high-risk drinkers.

Results

The odds ratio for an alcohol-related emergency department attendance following minimum unit pricing was 1.14 (95% confidence interval 0.90 to 1.44; p = 0.272). In absolute terms, we estimated that minimum unit pricing was associated with 258 more alcohol-related emergency department visits (95% confidence interval –191 to 707) across Scotland than would have been the case had minimum unit pricing not been implemented. The odds ratio for illicit drug consumption following minimum unit pricing was 1.04 (95% confidence interval 0.88 to 1.24; p = 0.612). Concerns about harms, including crime and the use of other sources of alcohol, were generally not realised. Stakeholders and the public generally did not perceive price increases or changed consumption. A lack of understanding of the policy may have caused concerns about harms to dependent drinkers among participants from more deprived areas.

Limitations

The short interval between policy announcement and implementation left limited time for pre-intervention data collection.

Conclusions

Within the emergency departments, there was no evidence of a beneficial impact of minimum unit pricing. Implementation appeared to have been successful and there was no evidence of substitution from alcohol consumption to other drugs. Drinkers and stakeholders largely reported not noticing any change in price or consumption. The lack of effect observed in these settings in the short term, and the problem-free implementation, suggests that the price per unit set (£0.50) was acceptable, but may be too low. Our evaluation, which itself contains multiple components, is part of a wider programme co-ordinated by Public Health Scotland and the results should be understood in this wider context.

Future work

Repeated evaluation of similar policies in different contexts with varying prices would enable a fuller picture of the relationship between price and impacts.

Trial registration

Current Controlled Trials ISRCTN16039407.

Funding

This project was funded by the National Institute for Health Research (NIHR) Public Health Research programme and will be published in full in Public Health Research; Vol. 9, No. 11. See the NIHR Journals Library website for further project information.

Recreational cannabis legalization and alcohol purchasing: a difference-in-differences analysis

Background

Whether recreational cannabis legalization is associated with changes in alcohol consumption (suggesting a potential substitution or complementary relationship) is a key question as cannabis policy evolves, particularly given the adverse health and social effects of alcohol use. Relatively little research has explored this question.

Methods

This study examined the association between recreational cannabis legalization and alcohol purchasing in the USA using an interrupted time series design. We used data from the Nielsen Consumer Panel (2004–2017) from 69,761 households in all 50 states to calculate monthly milliliters of pure ethanol purchased for four beverage categories (beer, wine, spirits, and all alcohol products). We used difference-in-differences models and robust cluster standard errors to compare changes in milliliters of pure ethanol purchased. We fit models for each beverage category, comparing three “policy” states that have legalized recreational cannabis (Colorado, Oregon, and Washington) to states that had not legalized recreational cannabis. In one set of models, a single control state was selected that matched pre-policy purchasing trends in the policy states. In another set, policy states were compared to all states that had not legalized recreational cannabis.

Results

Compared to all other states that did not legalize recreational cannabis, Colorado households showed a 13% average monthly decrease in purchases of all alcoholic products combined (estimate, 0.87; CI, 0.77, 0.98) and a 6% decrease in wine (0.94; CI, 0.89, 0.99). Estimates in Washington were suggestive of an increase in spirits purchased in both the unrestricted (1.24; CI, 1.12, 1.37) and restricted sample (1.18; CI, 1.02, 1.36). Oregon showed a significant decrease in monthly spirits purchased when compared to its selected comparator state (0.87; CI, 0.77, 0.99) and to all other states without legalized recreational cannabis (0.85; CI, 0.77, 0.95).

Conclusions

Results suggest that alcohol and cannabis are not clearly substitutes nor complements to one-another. Future studies should examine additional states as more time passes and more post-legalization data becomes available, use cannabis purchase data and consider additional methods for control selection in quasi-experimental studies.

Alcohol affordability: implications for alcohol price policies. A cross-sectional analysis in middle and older adults from UK Biobank

Background

Increasing the price of alcohol reduces alcohol consumption and harm. The role of food complementarity, transaction costs and inflation on alcohol demand are determined and discussed in relation to alcohol price policies.

Methods

UK Biobank (N = 502,628) was linked by region to retail price quotes for the years 2007 to 2010. The log residual food and alcohol prices, and alcohol availability were regressed onto log daily alcohol consumption. Model standard errors were adjusted for clustering by region.

Results

Associations with alcohol consumption were found for alcohol price (β = −0.56, 95% CI, −0.92 to −0.20) and availability (β = 0.06, 95% CI, 0.04 to 0.07). Introducing, food price reduced the alcohol price consumption association (β = −0.26, 95% CI, −0.50 to −0.03). Alcohol (B = 0.001, 95% CI, 0.0004 to 0.001) and food (B = 0.001, 95% CI, 0.0005 to 0.0006) price increased with time and were associated (ρ = 0.57, P < 0.001).

Conclusion

Alcohol and food are complements, and the price elasticity of alcohol reduces when the effect of food price is accounted for. Transaction costs did not affect the alcohol price consumption relationship. Fixed alcohol price policies are susceptible to inflation.

Substitute Addictions in Persons with Substance Use Disorders: A Scoping Review

Substitute addictions, addictive behaviors that sequentially replace each other's functions, have implications for recovery trajectories but remain poorly understood. We sought to scope the extent, range, and characteristics of research on substitute addictions in persons with substance use disorders. Method: Using Arksey and O'Malley's framework for scoping reviews, a systematic search was conducted to identify publications that referenced substitute addictions up to April 2018. Study characteristics were extracted and summarized to provide an overview of the extant literature. Results: The 63 included studies show that substitute addictions are terminologically and conceptually ambiguous. Much of the available literature is concentrated in developed contexts - and in particular the United States of America. While presentations varied, at least two sub-types of substitute addictions appeared: long-term replacement and temporary replacement. Existing theories suggest a multifactorial etiology. Conclusions: The findings suggest a strong need for: increased awareness of substitute addictions and its potential consequences for recovery; interventions that structure prevention and pre-, during-, and post-treatment interactions as well as future research to explore its nature and dynamics drawing on multiple methods.

Reduction in non-abstinent World Health Organization (WHO) drinking risk levels and drug use disorders: 3-year follow-up results in the US general population

BACKGROUND

To provide information on the clinical relevance of a reduction in the World Health Organization (WHO) drinking risk categories, we examined their relationship to an important indicator of how individuals feel and function: drug use disorders (DUDs), i.e., those involving substances other than alcohol.

METHOD

Current drinkers in a U.S. national survey (n = 22,005) were interviewed in 2001-02 and re-interviewed 3 years later. WHO drinking risk levels and DSM-IV-defined DUD were assessed at both waves. The relationship of changes in WHO drinking risk levels to the presence of DUD were examined using adjusted odds ratios (aOR).

RESULTS

At Wave 1, 2.5% of respondents were WHO very-high-risk drinkers, and 2.5%, 4.8%, and 90.2% were high-risk, moderate-risk, and low-risk drinkers, respectively. Among Wave 1 very-high-risk drinkers, significantly lower odds of DUD at Wave 2 were predicted by reductions in WHO risk levels of one, two or three levels (aOR = 0.15, 0.01, 0.24, respectively; all p-values <.0001). Among participants who initially were drinking at lower risk levels, reductions in drinking or abstinence were generally associated with significantly lower odds of DUD, although the results were less consistent.

CONCLUSIONS

Among very-high-risk drinkers, reduction in the WHO drinking risk categories were associated with lower risk of a DUD. These results add to findings indicating that reductions in WHO drinking risk levels are a meaningful indicator of how individuals feel and function and could therefore serve as informative outcomes in alcohol clinical trials. WHO risk levels can also guide treatment goals and clinical recommendations on drinking reduction.

Minimum unit prices for alcohol

Minimum unit prices (MUPs) have been proposed on the grounds that they can reduce alcohol consumption of the heaviest drinkers, without significantly burdening moderate drinkers. This paper examines the case for MUPs in an optimal tax framework. Such a policy can improve welfare when two conditions are both satisfied. First, beverage quality and quantity should be substitutes. Second, there should be more distortion to consumption of cheaper alcohol than to more expensive varieties. The consequences of a MUP for the optimal corrective tax are explored with a calibrated numerical example. This example illustrates how the optimal tax rate might be higher when used in isolation, than when a MUP is also being used.

Medical marijuana laws and adolescent use of marijuana and other substances: Alcohol, cigarettes, prescription drugs, and other illicit drugs

BACKGROUND

Historical shifts have taken place in the last twenty years in marijuana policy. The impact of medical marijuana laws (MML) on use of substances other than marijuana is not well understood. We examined the relationship between state MML and use of marijuana, cigarettes, illicit drugs, nonmedical use of prescription opioids, amphetamines, and tranquilizers, as well as binge drinking.

METHODS

Pre-post MML difference-in-difference analyses were performed on a nationally representative sample of adolescents in 48 contiguous U.S. states. Participants were 1,179,372U.S. 8th, 10th, and 12th graders in the national Monitoring the Future annual surveys conducted in 1991-2015. Measurements were any self-reported past-30-day use of marijuana, cigarettes, non-medical use of opioids, amphetamines and tranquilizers, other illicit substances, and any past-two-week binge drinking (5+ drinks per occasion).

RESULTS

Among 8th graders, the prevalence of marijuana, binge drinking, cigarette use, non-medical use of opioids, amphetamines and tranquilizers, and any non-marijuana illicit drug use decreased after MML enactment (0.2-2.4% decrease; p-values:<0.0001-0.0293). Among 10th graders, the prevalence of substance use did not change after MML enactment (p-values: 0.177-0.938). Among 12th graders, non-medical prescription opioid and cigarette use increased after MML enactment (0.9-2.7% increase; p-values: <0.0001-0.0026).

CONCLUSIONS

MML enactment is associated with decreases in marijuana and other drugs in early adolescence in those states. Mechanisms that explain the increase in non-medical prescription opioid and cigarette use among 12th graders following MML enactment deserve further study.

Clearing the haze: the complexities and challenges of research on state marijuana laws

As states increasingly liberalize marijuana laws, high-quality research is needed that will inform the public and policymakers about the health and societal impact of these laws. However, there are many challenges to studying marijuana policy, including the heterogeneity of the drug and its use, the variability in the laws and their implementation from state to state, the need to capture a wide variety of relevant outcomes, and the poorly understood influence of marijuana commercialization. Furthermore, current instruments generally fail to distinguish between types of users and lack accurate and detailed measures of use. This review provides a background on marijuana laws in the United States and an overview of existing policy research, discusses methodological considerations when planning analysis of state marijuana laws, and highlights specific topics needing further development and investigation.

Impacts of Changing Marijuana Policies on Alcohol Use in the United States

BACKGROUND

Marijuana policies are rapidly evolving. In the United States, recreational use of marijuana is now legal in 4 states and medical marijuana is legal in 23 states. Research evaluating such policies has focused primarily on how policies affect issues of price, access to, use, and consequences of marijuana. Due to potential spillover effects, researchers also need to examine how marijuana policies may impact use and consequences of alcohol.

METHODS

The current paper is a critical review of articles evaluating alcohol outcomes associated with marijuana decriminalization, medical marijuana legalization, and nonmedical or recreational marijuana legalization. We identified articles and reports through (1) online searches of EBSCO host database including Academic Search Premier, Econlit, Legal Collection, Medline, PsycARTICLES, and PsycINFO, as well as PubMed and Google Scholar databases; (2) review of additional articles cited in papers identified through electronic searches; and (3) targeted searches of state and local government records regarding marijuana law implementation. We reviewed studies with respect to their data sources and sample characteristics, methodology, and the margin of alcohol and marijuana use, timing of policy change, and the aspects of laws examined.

RESULTS

The extant literature provides some evidence for both substitution (i.e., more liberal marijuana policies related to less alcohol use as marijuana becomes a substitute) and complementary (i.e., more liberal marijuana policies related to increases in both marijuana and alcohol use) relationships in the context of liberalization of marijuana policies in the United States.

CONCLUSIONS

Impact of more liberal marijuana policies on alcohol use is complex, and likely depends on specific aspects of policy implementation, including how long the policy has been in place. Furthermore, evaluation of marijuana policy effects on alcohol use may be sensitive to the age group studied and the margin of alcohol use examined. Design of policy evaluation research requires careful consideration of these issues.

The effect of medical marijuana laws on adolescent and adult use of marijuana, alcohol, and other substances

We estimate the effect of medical marijuana laws (MMLs) in ten states between 2004 and 2012 on adolescent and adult use of marijuana, alcohol, and other psychoactive substances. We find increases in the probability of current marijuana use, regular marijuana use and marijuana abuse/dependence among those aged 21 or above. We also find an increase in marijuana use initiation among those aged 12-20. For those aged 21 or above, MMLs further increase the frequency of binge drinking. MMLs have no discernible impact on drinking behavior for those aged 12-20, or the use of other psychoactive substances in either age group.

Understanding the development of minimum unit pricing of alcohol in Scotland: a qualitative study of the policy process

Background

Minimum unit pricing of alcohol is a novel public health policy with the potential to improve population health and reduce health inequalities. Theories of the policy process may help to understand the development of policy innovation and in turn identify lessons for future public health research and practice. This study aims to explain minimum unit pricing’s development by taking a ‘multiple-lenses’ approach to understanding the policy process. In particular, we apply three perspectives of the policy process (Kingdon’s multiple streams, Punctuated-Equilibrium Theory, Multi-Level Governance) to understand how and why minimum unit pricing has developed in Scotland and describe implications for efforts to develop evidence-informed policymaking.

Methods

Semi-structured interviews were conducted with policy actors (politicians, civil servants, academics, advocates, industry representatives) involved in the development of MUP (n = 36). Interviewees were asked about the policy process and the role of evidence in policy development. Data from two other sources (a review of policy documents and an analysis of evidence submission documents to the Scottish Parliament) were used for triangulation.

Findings

The three perspectives provide complementary understandings of the policy process. Evidence has played an important role in presenting the policy issue of alcohol as a problem requiring action. Scotland-specific data and a change in the policy ‘image’ to a population-based problem contributed to making alcohol-related harms a priority for action. The limited powers of Scottish Government help explain the type of price intervention pursued while distinct aspects of the Scottish political climate favoured the pursuit of price-based interventions.

Conclusions

Evidence has played a crucial but complex role in the development of an innovative policy. Utilising different political science theories helps explain different aspects of the policy process, with Multi-Level Governance particularly useful for highlighting important lessons for the future of public health policy.

Can cannabis be considered a substitute medication for alcohol?

AIMS

Substituting cannabis for alcohol may reduce drinking and related problems among alcohol-dependent individuals. Some even recommend prescribing medical cannabis to individuals attempting to reduce drinking. The primary aim of this review is to assess whether cannabis satisfies the seven previously published criteria for substitute medications for alcohol [e.g. 'reduces alcohol-related harms'; 'is safer in overdose than alcohol'; 'should offer significant health economic benefits'; see Chick and Nutt ((2012) Substitution therapy for alcoholism: time for a reappraisal? J Psychopharmacol 26:205-12)].

METHODS

Literature review.

RESULTS

All criteria appear either satisfied or partially satisfied, though studies relying on medical cannabis patients may be limited by selection bias and/or retrospective designs. Individual-level factors, such as severity of alcohol problems, may also moderate substitution.

CONCLUSIONS

There is no clear pattern of outcomes related to cannabis substitution. Most importantly, the recommendation to prescribe alcohol-dependent individuals cannabis to help reduce drinking is premature. Future studies should use longitudinal data to better understand the consequences of cannabis substitution.

The role of alcohol price in young adult drinking cultures in Scotland

Minimum Unit Pricing (MUP) is one of the Scottish Government's key policy options to reduce alcohol consumption and related harm. Although strongly evidenced for efficacy in reducing headline population level consumption, efficacy in changing the role of alcohol in Scottish culture is unknown. Questions remain as to how MUP will play across population subgroups with different sensitivities to price. In this paper we explore the views of the young adult population and situate the influence of price paid for alcohol alongside broader cultural drivers of consumption. Qualitative data from two studies investigating the role of alcohol in the transition to adulthood from 130 participants (aged 16–30) are analysed to situate the influence of price paid in shaping drinking styles and practices. Findings highlight how considerations of price paid for alcohol compete with non-financial considerations associated with choosing to drink excessively, moderately or not at all. Two broad categories of response to potential price increases were anticipated by drinkers which indicate that young adults are not a homogenous group in relation to price sensitivity. These differences highlight the potential for variation in subgroup responses to a pricing policy conceived to be effective at a population level.

Intimate partner violence and specific substance use disorders: findings from the National Epidemiologic Survey on Alcohol and Related Conditions

The association between substance use and intimate partner violence (IPV) is robust. It is less clear how the use of specific substances relates to relationship violence. This study examined IPV perpetration and victimization related to the following specific substance use disorders: alcohol, cannabis, cocaine, and opioid. The poly substance use of alcohol and cocaine, as well as alcohol and marijuana, were also examined. Data were analyzed from wave two of the National Epidemiologic Survey on Alcohol and Related Conditions (2004-2005). Associations between substance use disorders and IPV were tested using logistic regression models while controlling for important covariates and accounting for the complex survey design. Alcohol use disorders and cocaine use disorders were most strongly associated with IPV perpetration, while cannabis use disorders and opioid use disorders were most strongly associated with IPV victimization. A diagnosis of both an alcohol use disorder and cannabis use disorder decreased the likelihood of IPV perpetration compared to each individual substance use disorder. A diagnosis of both an alcohol use disorder and cocaine use disorder increased likelihood of reporting IPV perpetration compared with alcohol use disorders alone but decreased likelihood of perpetration compared with a cocaine use disorder diagnosis alone. Overall, substance use disorders were consistently related to intimate partner violence after controlling for important covariates. These results provide further evidence for the important link between substance use disorders and IPV and add to our knowledge of which specific substances may be related to relationship violence.