Potential Impact of Minimum Unit Pricing for Alcohol in Ireland: Evidence from the National Alcohol Diary Survey

Changes in spirits purchasing behaviours after privatisation of government-controlled sales in Washington, USA

INTRODUCTION AND AIMS

The privatisation of the Washington Liquor Monopoly in 2012 offered a unique opportunity to study spirits purchasing behaviour changes from a government to licensed system.

DESIGN AND METHODS

Four representative cross-sectional surveys of adults aged 18 and older in Washington state were recruited between January 2014 and October 2015 (Wave 1, N = 1202; W2, N = 804; W3, N = 823; W4, N = 662). Analyses compared spirits purchasing behaviours before privatisation from retrospective reports to current reports in the areas of travel distance, spirits quality, purchase frequency and size of bottle. Respondents also directly reported on changes in convenience, selection and prices.

RESULTS

No significant changes were found in these aspects of purchasing. However, subgroup analyses found that younger drinkers 18-29 reduced travel distance and increased purchase frequency while drinkers aged 50 and older travelled further. Reduced travel distances were associated with grocery and drug stores while increased travel distances were associated with liquor superstores, wholesale stores and government stores in bordering states. Respondents reported that liquor purchasing was more convenient after privatisation but that the selection of spirits was better and prices were lower in the government-controlled stores.

DISCUSSION AND CONCLUSIONS

The government monopoly stores were viewed as offering a wider selection of products and as having lower prices than those in the privatised system. The variety of store types in the licensed system allowed drinkers to select stores based on convenience, selection or prices, so that travel times increased for some buyers, presumably those seeking lower prices or a wider selection.

Public health policies and alcohol-related liver disease

Alcohol-related liver disease (ALD) represents a major public health problem worldwide. According to the World Health Organization, the highest levels of per capita alcohol consumption are observed in countries of the European Region. Alcohol consumption is also alarmingly increasing in developing countries. ALD is one of the main contributors to the burden of alcohol-attributable deaths and disability. In the United States, severe forms of ALD such alcoholic hepatitis have increased in the last decade and in the United Kingdom, three-quarters of liver-related mortality results from alcohol consumption. Besides genetic factors, there is strong evidence that the amount of alcohol consumed plays a major role in the development of advanced ALD. Establishing effective public health policies is therefore mandatory to reduce the burden of ALD. Since the 90s, major public health institutions and governments have developed a variety of policies in order to reduce the harm caused by excessive drinking. These policies encompass multiple factors, from pricing and taxation to advertising regulation. Measures focused on taxation and price regulation have been shown to be the most effective at reducing alcohol-related mortality. However, there are few studies focused on the effect of public policies on ALD. This review article summarises the factors influencing ALD burden and the role of different public health policies.

Spirits purchasing and marijuana use behaviors of risky drinkers in the state of Washington from 2014 to 2016

BACKGROUND

Few studies have evaluated alcoholic beverage purchasing behaviors, which are relevant to the design and effectiveness of alcoholic beverage control policies. Focusing on spirits purchasing among spirits drinkers, this study compares purchasing behaviors between risky and non-risky drinkers and across drinking patterns among those observed drinking at both levels.

METHODS

A rolling panel of 794 spirits drinkers in the state of Washington were surveyed between two and five times at 6-month intervals during 2014, 2015 and 2016 regarding their alcohol use, spirits purchasing and marijuana use frequency. Purchasing behaviors assessed for spirits were the frequency of purchasing and the travel time, unit cost, bottle size and store type from the respondents most recent purchase. Alcohol use was categorized at each measurement as risky or not using US NIAAA guidelines.

RESULTS

Risky drinkers were more likely to purchase spirits, purchase spirits more frequently, purchase larger spirits containers and use marijuana occasionally, but not frequently. Among drinkers who were risky only in some survey waves, during risky waves they were more likely to purchase more frequently, pay less per liter for spirits purchased, buy larger sized containers of spirits and use marijuana occasionally.

CONCLUSIONS

Drinkers chose to purchase lower cost spirits in larger containers when they were drinking more heavily compared to times when they were drinking within US low-risk guidelines. Findings also support complementarity between heavier drinking and marijuana use among spirits drinkers in a state with legal recreational marijuana sales.

Heavy Drinkers and the Potential Impact of Minimum Unit Pricing-No Single or Simple Effect?

Aims

To explore the potential impact of a minimum unit price (MUP: 50 pence per UK unit) on the alcohol consumption of ill Scottish heavy drinkers.

Methods

Participants were 639 patients attending alcohol treatment services or admitted to hospital with an alcohol-related condition. From their reported expenditure on alcohol in their index week, and assuming this remained unchanged, we estimated the impact of a MUP (50 ppu) on future consumption. (Around 15% purchased from both the more expensive on-sale outlets (hotels, pubs, bars) and from off-sales (shops and supermarkets). For them we estimated the change in consumption that might follow MUP if (i) they continued this proportion of 'on-sales' purchasing or (ii) their reported expenditure was moved entirely to off-sale purchasing (to maintain consumption levels)).

Results

Around 69% of drinkers purchased exclusively off-sale alcohol at <50 ppu. Their drinking, post MUP, may reduce by a mean of 33%. For this group, from a population of very heavy, ill consumers, we were unable to show a differential effect across multiple deprivation quintiles. For other drinkers there might be no reduction, especially if after MUP there were many products priced close to 50 ppu. Moving away from on-sales purchases could support, for some, an increase in consumption.

Conclusions

While a proportion of our harmed, heavy drinkers might be able to mitigate the impact of MUP by changing purchasing habits, the majority are predicted to reduce purchasing. This analysis, focusing specifically on harmed drinkers, adds a unique dimension to the evidence base informing current pricing policy.

Short Summary

From drink purchasing data of heavy drinkers, we estimated the impact of legislating £0.50 minimum unit price. Over two thirds of drinkers, representing all multiple deprivation quintiles, were predicted to decrease alcohol purchasing; remainder, hypothetically, could maintain consumption. Our data address an important gap within the evidence base informing policy.

Evidence for the effectiveness of minimum pricing of alcohol: a systematic review and assessment using the Bradford Hill criteria for causality

OBJECTIVES

To assess the evidence for price-based alcohol policy interventions to determine whether minimum unit pricing (MUP) is likely to be effective.

DESIGN

Systematic review and assessment of studies according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, against the Bradford Hill criteria for causality. Three electronic databases were searched from inception to February 2017. Additional articles were found through hand searching and grey literature searches.

CRITERIA FOR SELECTING STUDIES

We included any study design that reported on the effect of price-based interventions on alcohol consumption or alcohol-related morbidity, mortality and wider harms. Studies reporting on the effects of taxation or affordability and studies that only investigated price elasticity of demand were beyond the scope of this review. Studies with any conflict of interest were excluded. All studies were appraised for methodological quality.

RESULTS

Of 517 studies assessed, 33 studies were included: 26 peer-reviewed research studies and seven from the grey literature. All nine of the Bradford Hill criteria were met, although different types of study satisfied different criteria. For example, modelling studies complied with the consistency and specificity criteria, time series analyses demonstrated the temporality and experiment criteria, and the analogy criterion was fulfilled by comparing the findings with the wider literature on taxation and affordability.

CONCLUSIONS

Overall, the Bradford Hill criteria for causality were satisfied. There was very little evidence that minimum alcohol prices are not associated with consumption or subsequent harms. However the overall quality of the evidence was variable, a large proportion of the evidence base has been produced by a small number of research teams, and the quantitative uncertainty in many estimates or forecasts is often poorly communicated outside the academic literature. Nonetheless, price-based alcohol policy interventions such as MUP are likely to reduce alcohol consumption, alcohol-related morbidity and mortality.