Reducing alcohol use through alcohol control policies in the general population and population subgroups: a systematic review and meta-analysis
Systematic review article
Summary
The researchers estimate the effects of alcohol taxation, minimum unit pricing (MUP), and restricted temporal availability on overall alcohol consumption and review their differential impact across sociodemographic groups.
Web of Science, Medline, PsycInfo, Embase, and EconLit were searched on 08/12/2022 and 09/26/2022 for studies on newly introduced or changed alcohol policies published between 2000 and 2022.
The researchers combined data using random-effects meta-analyses. Risk of bias was assessed using the Newcastle–Ottawa Scale.
Of 1887 reports, 36 were eligible.
- Doubling alcohol taxes or introducing MUP (Int$ 0.90/10 g of pure alcohol) reduced consumption by 10%.
- Restricting alcohol sales by one day a week reduced consumption by 3.6%.
Substantial between-study heterogeneity contributes to high levels of uncertainty and must be considered in interpretation.
Pricing policies resulted in greater consumption changes among low-income alcohol users, while results were inconclusive for other socioeconomic indicators, gender, and racial and ethnic groups. Research is needed on the differential impact of alcohol policies, particularly for groups bearing a disproportionate alcohol-attributable health burden.
Research in context
Evidence before this study
Despite the effectiveness of key alcohol control policies being widely agreed on, meta-analyses on their impact on alcohol use relying on real-world evidence are surprisingly scarce.
Through systematic searches on Web of Science, Medline, PsycInfo, Embase, and EconLit, the researchers identified existing reviews published between 2000 and 2022 (n = 36; alcohol taxation: 14, minimum unit pricing (MUP): 2, temporal availability: 10, multiple policies: 10) that indicated clearly that increases in alcohol excise taxes, the introduction of MUP, and restrictions of temporal alcohol availability were mostly associated with a reduction in alcohol consumption.
However, few of these reviews have quantified this association, and none have systematically studied the differential impact of alcohol control policies by sociodemographic factors such as gender, socioeconomic status, and race and ethnicity.
Added value of this study
The current study reviews the evidence put forth by a total of 36 studies published since January 2000. Through rigorous steps in extracting comparable data, the researchers provide a systematic quantification of those studies and estimated the impact of three major alcohol control policies on alcohol consumption levels. In addition, all available evidence on alcohol policy effects conditional on gender, socioeconomic status, and race and ethnicity were summarised narratively.
The greatest reduction in alcohol consumption was seen following the introduction of pricing policies, particularly for the most affordable alcohol. Based on a limited number of available studies (n = 9), the researchers found that following the introduction of pricing policies, alcohol consumption reduced the most among low-income groups, while the evidence was inconclusive for other sociodemographic factors.
Implications of all the available evidence
Taxation increases, the introduction of MUP, and restrictions of temporal availability all contribute to a decline in consumption levels and consequently alcohol-attributable harm.
However, more research is needed on their impact on health inequalities between different sociodemographic groups.
Alcohol control policies need to be systematically evaluated with respect to their potential contribution to mitigate health inequalities through differential effects on alcohol use.
Background
Alcohol use is among the leading risk factors for premature mortality, with an increasing number of alcohol-attributable premature deaths over the last two decades globally.
This trend is partly driven by an accelerated increase in alcohol-attributable deaths among disadvantaged populations in many countries, such as people of low socioeconomic status (SES). In the United States (US), for example, alcohol-related harms contribute to a widening gap in life expectancy between men and women of low and high SES.
Given alcohol’s role in growing health inequalities, tackling alcohol use goes beyond reducing alcohol’s harm and contributes to achieving various United Nations Sustainable Development Goals (SDG), including a reduction of inequalities (SDG target 10.2) by addressing health disparities.
To reverse trends of increasing alcohol-attributable harms and health inequalities, alcohol control policies shown to reduce alcohol use and related harms in a cost-effective manner play a key role.
The World Health Organisation (WHO) recommends several alcohol policy interventions to effectively and cost-effectively lower alcohol consumption levels and related harms in society.
Three policies, the so-called “best buys”, stand out in not only being the most cost-effective policies, but also relatively easy to implement:
- increasing alcohol prices through taxation or minimum pricing,
- restricting the temporal and spatial availability of alcoholic beverages, and
- bans or comprehensive restrictions of alcohol marketing.
However, two key questions have not yet been addressed in prior reviews:
- First, a quantification of their impact on consumption in real-world settings is pending, although their effectiveness, particularly in reducing alcohol-attributable harm, has been well established.
- Second, while systematic differences in both the alcohol use patterns and the related harms have been observed across both SES and racial and ethnic groups, there has been minimal investigation into whether these policies can mitigate against growing inequalities in the alcohol-attributable disease burden through differential effects on alcohol use.
Drawing on experiences from countries that have implemented alcohol control policies within the past decades, the researchers conducted a systematic review and meta-analysis to quantify the effects of alcohol control interventions on alcohol consumption. Specifically, they focused on those policies implemented at the state or national level, which seem to yield almost immediate results:
- alcohol taxation (levying an excise tax on alcoholic beverages),
- minimum pricing or minimum unit pricing (MP/MUP; setting a floor price for alcoholic beverages in general or for a certain amount of pure alcohol, respectively), and
- temporal availability of alcoholic beverages (restricting the hours per day or days per week to purchase alcoholic beverages).
As a secondary objective, the researchers evaluated whether the intervention effects are conditional on sociodemographic factors (i.e., gender, SES, and race and ethnicity). They also considered, where reported, specific effects for any intersectional groups defined by combinations of these factors (e.g., women of low SES).
Results
Of the 1887 research reports identified in the literature search, 36 reports were eligible for inclusion. These reports covered more than 25 policy interventions in 14 countries (see appendix p. 15).
Reports used either longitudinal (individual-level cohort or panel data: n = 8; aggregated data representing a full assessment of alcohol use at the population level: n = 18), repeated cross-sectional (n = 8), cross-sectional (n = 1), or mixed study designs (longitudinal and repeated cross-sectional; n = 1). Table 1 provides an overview of each report’s study characteristics.
The researchers present the key findings of the quantitative and qualitative summary for each policy for the general population and subgroups of interest (for results on consumption patterns, see appendix p. 18).
Policy 1: alcohol taxation
The majority of tax interventions included in the systematic review reflect increases in alcohol excise taxes, including six studies–all located in the US–that provide tax elasticities.
Tax reforms were either specific to certain alcoholic beverages such as the beer and ready-to-drink (RTD) tax increases in Australia, or more complex by affecting multiple alcoholic beverages to varying degrees, such as in Illinois (US), Lithuania, or Thailand.
Four studies located in Australia, Hong Kong, and the US evaluated the impact of tax changes on beverage prices, which is the prerequisite for taxes to affect consumption. Specifically, excise taxes levied on alcohol are intended to increase beverage prices, thereby lowering their affordability and consumption.
Based on the identified studies, however, taxes were usually over- or under-shifted. For example, following the 2008 tax cut on beer and wine in Hong Kong, the price for wine dropped by 14.3%, while beer prices decreased only marginally.
Similarly, no considerable changes in beer prices were observed following the 2000/2001 Australian beer tax reforms.
In the US, an over-shifting of wine and spirits taxes was observed (i.e., prices increased above the tax increase), while beer taxes were under-shifted (i.e., prices did not increase to the same extent as the tax increase).
Quantitative summary
Fig. 2 depicts the association of tax changes and consumption based on studies included in the quantitative summary (n = 10 studies).
Alcohol tax changes were inversely associated with consumption, suggesting an average reduction in alcohol consumption of 10.8% within the first year of a 100% tax increase.
This finding was robust against the exclusion of studies on tax decreases, studies with a critical risk of bias, and the one study using a repeated cross-sectional study design; and did not considerably differ from the one-level model.
There was substantial heterogeneity between studies that remained unexplained, and no indication for a publication bias given symmetry of the funnel plot. Accounting for the assessment of alcohol use and the policy design (i.e., whether the tax policy concerned a single or multiple beverage categories) did not alter the overall result.
Qualitative summary
One additional study assessed the immediate impact of a number of tax increases on alcohol consumption between 2000 and 2020 in Estonia, Latvia, Lithuania, and Poland using time-series analysis. These tax increases led to a significant reduction in per capita consumption of 0.89 L. While this study was not included in the meta-analysis given the range of tax reforms implemented across countries and years, the 2017 Lithuanian tax reform was accounted for by another study.
Very few studies (n = 3) assessed long-term changes in alcohol consumption following tax policy reforms. For tax increases, there was limited evidence that changes in RTD consumption persisted up to nine years after the RTD tax was increased in Australia in 2009.
For tax cuts, however, persistent consumption changes were not observed.
In Russia, for example, where the real term tax dropped by almost 50% following hyperinflation in 1998 and 1999, vodka and liquor retail sales increased markedly in the same years, but declined in subsequent years, although tax levels remained low.
Cross-beverage effects play an important role in the evaluation of tax effectiveness, as there is a risk that some alcohol users may shift their consumption to other beverages, if taxes are not raised for all alcoholic beverages. Such cross-beverage effects were indeed observed in those countries where taxes were implemented just for some beverages. For example, while the consumption of RTDs decreased shortly after the RTD tax increase in Australia, the consumption of ciders and spirits increased.
Likewise, the marginal beer tax increase in Illinois, compared to the much higher tax increases on wine and spirits, led to a rise in beer sales by 5.5%.
Differences in policy effects across sociodemographic groups
Research on the effectiveness of alcohol taxation conditional on sociodemographics was scarce. Among men, but not among women who had at least six alcoholic drinks in the past six months, spirits consumption increased significantly following reductions in the spirits tax in Switzerland.
This gender difference was, however, not supported by another Swiss study including less frequent alcohol users and alcohol abstainers.
With regard to SES, there was some indication that tax changes affected low-income alcohol users to a greater extent, but this pattern was not observed when education or occupation was used as SES indicator.
Results across racial and ethnic groups were mixed, pointing to some divergent tax elasticities. For example, an increase in alcohol taxes was associated with a significant decrease in consumption levels and past-month prevalence of alcohol use among non-Hispanic Black women and Hispanic women and men in one study, while another study identified Hispanics to be least responsive to tax changes.
Policy 2: minimum unit pricing
MUP was recently introduced in Scotland and Wales (UK, Int$ 0.88 per 10 g of pure alcohol), and the Northern Territory (Australia, Int$ 0.91 per 10 g of pure alcohol).
In the Canadian provinces British Columbia (BC) and Saskatchewan (SK) MUPs were already in place and increased over the study period.
As there was no fixed price per unit alcohol before the introduction of a MUP, the researchers report the results of studies on the introduction and the increase of MUPs separately. There was no study evaluating MP policies that met the inclusion criteria.
Quantitative summary
Four studies investigated the immediate impact of the introduction of MUP on beverage-specific and overall consumption.
Within a year post intervention, average alcohol consumption decreased by 11.7%.
Two of these studies also looked at consumption changes two years post intervention, suggesting persistence of consumption declines.
Sensitivity analysis using a random-effects meta-regression model without random intercept revealed that the immediate reduction in consumption following the introduction of MUP was driven by a steep decrease in cider- and RTD-specific consumption.
Moreover, significant reductions in consumption following the introduction of MUP were only observed when using individual-level consumption data, which all had a critical risk of bias.
There was substantial between-study heterogeneity in the main models which did not diminish when excluding individual studies.
Qualitative summary
In the two Canadian provinces, BC and SK, a 10% increase in the MUP was associated with a significant reduction in per capita consumption for beer (BC: −1.5%, SK: −10.6%), wine (BC: −8.9%, SK: −4.6%), and spirits (BC: −6.8%, SK: −5.9%), as well as for overall consumption (BC: −3.4%, SK: −8.4%).
Differences in policy effects across sociodemographic groups
In Scotland, decreases in consumption following the MUP policy that were observed in the overall population were found to be driven primarily by women.
Evidence is mixed on whether the impact of MUP differs by SES, while there was no study on the effectiveness conditional on race and ethnicity. In Scotland, decreases in weekly consumption levels appeared to concentrate in lower rather than higher income groups.
However, this discernible pattern was not supported if deprivation based on the geographical area of living and occupation-based social grade were used as SES indicators.
There was also inconsistent evidence on whether MUP led to a shift towards low-strength beer in certain income groups, with one study supporting such a shift in mid-income households in Scotland but another not.
Policy 3: temporal availability
Regulations on the temporal availability of alcoholic beverages were amended in nine countries. Hours of off-premise alcohol sales were modified in Estonia, Latvia, and Lithuania, as well as in the Russian Federation, while policies regulating on-premise alcohol sales were implemented in Spain and the UK.
In the Canadian province of Ontario, Sweden, and the US, alcohol sales were either permitted or banned on one additional day.
Quantitative summary
The restriction of alcohol sales by one day led to a 3.6% decrease in alcohol consumption, according to five studies (Fig. 4).
This overall decline was driven by a significant reduction in beer and spirits consumption, whereas the average decrease in wine and overall alcohol consumption was not significantly different from zero.
Excluding the only repeated cross-sectional study did not alter the overall findings. There was substantial between-study heterogeneity, which diminished markedly after excluding one study with a critical risk of bias. Excluding this study, however, did only marginally reduce the overall effect. There was no indication of publication bias.
Qualitative summary
The regulation of on-premise and off-premise alcohol sales hours were also shown to impact alcohol consumption. With regard to on-premise alcohol sales, earlier bar closing hours in Spain resulted in a marked decline in annual average household spending on alcohol, as well as daily and weekly wine consumption in men but not in women.
In England and Wales, where the 2003 Licensing Act allowed 24-h alcohol sales, changes in on-premise sales hours had little impact on consumption; however, it is important to note that most consumption sites have not substantially extended their opening hours following the Licensing Act.
For off-premise consumption, some effects on alcohol consumption were found.
In the Russian Federation, later closing times of off-premise outlets were linked to higher monthly consumption levels, while a later opening of stores in the morning was associated with lower consumption levels. Although these restrictions did not include beer, a substitution effect, that is, a shift towards beer consumption, was not identified.
In Estonia, Latvia, and Lithuania, night-time alcohol sales bans were not associated with per capita consumption.
Differences in policy effects across sociodemographic groups
None of the included studies explored the impact of availability restrictions conditional on SES or race and ethnicity.
Discussion
This systematic review shows that, consistent with prior research, alcohol control policies that raise alcohol prices and reduce the temporal availability of alcoholic beverages lead to a reduction in overall alcohol consumption, with some differential effects identified across sociodemographic groups.
Specifically, the researchers found that doubling alcohol excise taxes or introducing a MUP of about Int$ 0.90 per 10 g of pure alcohol results in an average 10% decrease in the level of alcohol consumption within the same year, with potentially larger reductions in low-income compared to more affluent groups.
Restricting the temporal availability of alcohol by one day a week also reduces consumption, albeit to a lesser extent than pricing policies.
Findings were inconclusive as to whether these policies differentially affect women and men, and there was no study that investigated the differential impact of temporal availability policies by SES or race and ethnicity (see Fig. 5). The sparsity of studies addressing policy effects conditional on gender, SES, and race and ethnicity reveal a major research gap and negligence of such subgroup effects.
In line with prior research, the researchers found pricing policies to be the most promising at lowering consumption levels.
The reverse linear association of excise taxes and consumption suggest that stronger declines in consumption can be expected with steeper policy-driven price changes, while modest price increases may prove ineffective. This is further supported by sharp declines in cider consumption that were observed in Scotland and Wales following the MUP policy, as the prices of ciders increased most significantly following this policy change.
In Scotland, for example, the mean price per unit cider increased by 27% in 2018/2019, while the prices per unit of beer, wine, and spirits increased by around 15%.
At the same time, consumption of alcoholic beverages other than ciders did not increase in these countries, suggesting that there was no shift in consumption, but rather an overall decrease following the introduction of MUP.
When evaluating the impact of these pricing policies, it is worth noting that there is a significant difference between MUP and alcohol taxation.
While the MUP raises the floor price of alcoholic beverages, excise taxes will–at least in theory–increase the prices of all alcoholic beverages affected by the policy. However, tax increases do not always translate into higher prices. Prior research on pass-through rates, as well as the literature presented in this review demonstrate that taxes are often under- or over-shifted, which may explain some of the observed heterogeneity in the data.
With regard to MUP, it is important to bear in mind that the data in this review is based on an absolute threshold in international dollars, based only on the high-income countries Australia, Scotland, and Wales. However, the introduction of this measure is likely to have different impacts depending on the wealth of the countries.
Restrictions on the availability of alcohol, including restricted sales hours and days, were also effective in lowering alcohol consumption. Spontaneous alcohol use in particular appears to be affected by these restrictions, i.e., alcohol use on the day or time targeted by the policy. This observation is consistent with declines in injuries and emergency room admissions seen on days where alcohol is less available given sales restrictions.
Moreover, the researchers found some beverage-specific effects that may be related to beverage preferences, reflected by more pronounced decreases in beer and spirits consumption in Canada, Sweden, and the US, while reduced bar opening hours in Spain were linked to a decline of wine consumption.
The second objective of this research was to quantify policy effects conditional on sociodemographic factors, which, however, was not possible given the lack of research on this topic. From the very few studies available, the researchers conclude that there is a differential effect of pricing policies on consumption across population subgroups. Specifically, the impact of pricing policies varied by income, as seen for alcohol taxation and MUP.
Such a differential effect was, however, not consistently observed for other SES indicators, such as occupation, suggesting that the moderating effect observed for income reflects the role of affordability in price-driven consumption reductions. On the other hand, when studying alcohol-related harms, education-based inequalities in all-cause mortality were found to have decreased in Lithuania following the substantial excise tax increases in 2017.
Given the limited number of studies available, further research is needed to elucidate whether the differential policy effects are income-specific or also apply to other SES indicators. For gender and race and ethnicity, research was even more scarce and also inconclusive, preventing any conclusions about differential policy effects.
There are some caveats to consider when drawing conclusions based on this review.
First, and most importantly, the evidence presented in this review is confined by a relatively small number of studies, almost exclusively from high-income countries. This limitation may be attributed to the use of English search terms.
Second, the study selection criteria led to the exclusion of reports that centred on countries where complex alcohol policy changes happened, such as Finland’s 2004 tax reform, which coincided with new alcohol cross-border purchasing regulations and Estonia’s entry to the European Union.
This limitation is, however, also a strength of this research, as this rigorous approach allowed the researchers to study single-policy effectiveness.
The majority of included reports relied on longitudinal data, with only two repeated cross-sectional studies included in the quantitative summary.
Third, in quantifying the impact of alcohol taxation, the researchers focused on actual tax shifts rather than price elasticities. As discussed earlier, tax changes may not be fully reflected in the beverage price, which we were unable to control for as very few studies reported on real price changes following tax reforms. As previous studies have therefore often looked at price elasticities, the current study is an important contribution in its focus on tax changes.
Fourth, for studies reporting consumption changes among alcohol users only, the researchers assumed that the prevalence of alcohol use remained the same pre and post interventions (see methods section). This assumption was challenged by studies showing that taxation and availability policies also affect the prevalence of alcohol use. Given the tendency of the prevalence of alcohol use to decrease rather than to increase with stricter policies, this assumption may have led to an underestimation of the true effect in the overall population.
Finally, the researchers have assumed that increasing the restrictiveness of a policy would have an equivalent (inverse) impact to loosening that policy (for sensitivity analyses, see appendix p. 19, 24).
An evidence-informed implementation of alcohol control policies can lead to an immediate reduction in population-level consumption. Such a reduction in consumption may also be sustained in the long-term, presuming that the policies are designed to remain effective over time, which is often not the case.
With lower per capita consumption levels, alcohol-related harms would decrease too, preventing thousands of alcohol-attributable premature deaths globally.
It remains unclear, however, whether different sociodemographic groups benefit equally from these health policies and whether they can help mitigate health inequalities. In light of growing inequalities in the alcohol-attributable health burden, research on the effectiveness of alcohol policies conditional on sociodemographic factors, including gender, SES, and race and ethnicity, must be prioritised. Moreover, efforts to address alcohol-related health inequalities must be accompanied by upstream policies targeting the root causes of these social inequalities.
