Evaluating the impact of alcohol minimum unit pricing on deaths and hospitalisations in Scotland: a controlled interrupted time series study
Research article
Key findings
The authors present a timely, high-quality evaluation of the effect of Scotland’s Alcohol Minimum Unit Pricing policy on wholly alcohol-attributable hospital admissions and deaths, that is hospital stays and deaths that are directly caused by alcohol consumption.
They researchers find reductions in both outcomes, with larger reductions in the most deprived areas, thereby reducing the stark health inequalities in alcohol-related deaths in Scotland. Hospital stays for these conditions decreased by 4% and deaths by 13% on average.
The study estimated that following the introduction of the MUP policy, 156 deaths per year were averted.
Researchers also found that reductions in deaths due to alcohol were greatest for men and for those living in the 40% most deprived areas of Scotland.
According to the BBC, Dr Grant Wyper, public health intelligence adviser at PHS, said:
The results published are very encouraging in addressing this inequality, and the overall scale of preventable harm which affects far too many people.”
Dr Grant Wyper, public health intelligence adviser at Public Health Scotland
The report authors acknowledged some limitations to the study, including that there was an impact on hospital capacity and attendance during the Covid-19 pandemic.
Context
This research is part of the ‘minimum unit pricing evaluation portfolio’. This means the research was a pre-planned part of the evaluation of the MUP policy in Scotland. A study protocol and analysis plan were published in advance, which is good practice, and these are further reasons to be confident in the findings. The Scottish government is funding this research.
The authors used a robust, “gold standard” evaluation method for public health policies – a controlled interrupted time-series analysis. This method capitalizes on the fact that Minimum Unit Pricing was introduced in Scotland but not England, and uses this to estimate what would have happened in Scotland had the policy not been introduced.
The basic idea is to compare trends in alcohol-specific health outcomes before and after the introduction of Minimum Unit Pricing. If changes happen in both countries, they cannot be caused by the policy which only affected Scotland, but Scotland-only changes are highly likely to be caused by Minimum Unit Pricing, given there were no other major alcohol-related changes that occurred in only one of the countries in the meantime. In this way, the authors’ analyses can discount alternative explanations for the changes in deaths and hospital admissions, for example changes in alcohol taxation, disposable incomes or beverage market developments.
Minimum unit pricing was introduced to save lives, and this latest report shows it is doing just that,” said Dr Alastair MacGilchrist, the chair of expert clinician partnership at Scottish Health Action on Alcohol Problems, as per The Guardian.
Dr Alastair MacGilchrist, the chair of expert clinician partnership at Scottish Health Action on Alcohol Problems
Summary
Background
Since May 1, 2018, every alcoholic drink sold in Scotland has had minimum unit pricing (MUP) of £0·50 per unit. Previous studies have indicated that the introduction of this policy reduced alcohol sales by 3%.
The researchers aimed to assess whether this has led to reductions in alcohol-attributable deaths and hospitalisations.
Methods
Study outcomes, wholly attributable to alcohol consumption, were defined using routinely collected data on deaths and hospitalisations.
Controlled interrupted time series regression was used to assess the legislation’s impact in Scotland, and any effect modification across demographic and socioeconomic deprivation groups. The pre-intervention time series ran from Jan 1, 2012, to April 30, 2018, and for 32 months after the policy was implemented (until Dec 31, 2020).
Data from England, a part of the UK where the intervention was not implemented, were used to form a control group.
Findings
MUP in Scotland was associated with a significant 13.4% reduction in deaths wholly attributable to alcohol consumption.
Hospitalisations wholly attributable to alcohol consumption decreased by 4.1%.
Effects were driven by significant improvements in chronic outcomes, particularly alcoholic liver disease. Furthermore, MUP legislation was associated with a reduction in deaths and hospitalisations wholly attributable to alcohol consumption in the four most socioeconomically deprived deciles in Scotland.
Interpretation
The implementation of MUP legislation was associated with significant reductions in deaths, and reductions in hospitalisations, wholly attributable to alcohol consumption. The greatest improvements were in the four most socioeconomically deprived deciles, indicating that the policy is positively tackling deprivation-based inequalities in alcohol-attributable health harm.
Funding
Scottish Government.
Meaning
The new study results confirm earlier real-world evidence from Scotland that alcohol consumption decreased following the introduction of minimum unit pricing.
The results are in line with findings of modelling studies from before MUP was introduced. The decrease in deaths was bigger in the more disadvantaged group, which again fits with the findings from modelling studies that minimum pricing helps to narrow health inequalities.
This study only looks at the first 32 months of minimum pricing in Scotland. Previous evidence suggests these health gains should continue into the future, although high levels of inflation risk watering down the impact of the policy as it currently stands.
Wholly attributable outcomes represent only a small part of the likely effect of Minimum Unit Pricing on overall health and wellbeing, but one that can be estimated with far greater certainty than where alcohol is just one of a number of contributory factors.
This study provides the clearest evidence to date that minimum unit pricing (MUP) has reduced the harm caused by alcohol in Scotland.
This study provides clear evidence that heavier alcohol users are consuming less alcohol due to MUP because alcohol-specific deaths are concentrated among people with very high levels of alcohol consumption.
Expert reactions via the Science Media Centre
An observational study published in the Lancet looks at alcohol-related deaths and hospitalisations in Scotland since the minimum unit pricing for alcohol policy (MUP) was brought in by the Scottish government in 2018.
This Roundup accompanied an SMC Briefing.
Dr Sadie Boniface, Head of Research, Institute of Alcohol Studies; and Visiting Researcher, King’s College London, said:
“This important study adds to a large and consistent evidence base on the effectiveness of alcohol pricing policies.
This is high quality research using official data on deaths and hospitalisations, and the main finding of a 13% reduction in deaths from alcohol is highly significant, in both health and statistical terms. The authors appropriately use England as a control group and have addressed other factors such as the impact of the COVID-19 pandemic and associated restrictions.
Dr Sadie Boniface, Head of Research, Institute of Alcohol Studies
Prof Petra Meier, Professor of Public Health and MRC Investigator, University of Glasgow, said:
The authors present a timely, high-quality evaluation of the effect of Scotland’s Minimum Unit Pricing policy on wholly alcohol-attributable hospital admissions and deaths, that is hospital stays and deaths that are directly caused by alcohol consumption. They find reductions in both outcomes, with larger reductions in the most deprived areas, thereby reducing the stark health inequalities in alcohol-related deaths in Scotland. Hospital stays for these conditions decreased by 4% and deaths by 13% on average.
We need to be aware that wholly attributable outcomes represent only a small part of the likely effect of Minimum Unit Pricing on overall health and wellbeing, but one that can be estimated with far greater certainty than where alcohol is just one of a number of contributory factors. So we are missing here potentially large additional effects on alcohol-related deaths from cancer, liver cirrhosis, accidents, violence or suicide, but as the authors explain, there is no easy way to robustly estimate these effects yet, as several of these outcomes result from drinking over a number of years, so recent consumption changes would not yet show up in deaths statistics.
Prof Petra Meier, Professor of Public Health and MRC Investigator, University of Glasgow