title: The epidemiology of alcohol use disorder and public health policies to tackle alcohol-related harm: a case study of Scotland and the minimum unit pricing for alcohol
Creators: name: Manca, Francesco
Publisher: name: University of Glasgow
Year: 2024

description: Alcohol use disorder (AUD) in Scotland is a public health concern. In 2021, it was estimated that 23% of the Scottish population drank at hazardous or harmful levels, and 17% of children lived with at least one parent with AUD. In 2015, AUD contributed to 6.5% of all deaths. Alarmingly, Scotland also has high figures on alcohol-related harms compared to neighbouring UK nations like England and Wales. For instance, in 2018, Scottish alcoholspecific death rates were nearly twice as high for men and 87% higher for women compared to England &amp; Wales; consumption was also higher in Scotland, with 9% more alcohol sold per adult in 2019 than in England. Moreover, alcohol-related harms affect some population groups more severely than others, with important implications for health inequalities. In the last two decades, the Scottish Government has introduced a series of public health strategies to tackle alcohol-related harms and the associated inequalities. The last being minimum unit pricing (MUP) for alcohol, a novel pricing policy whose promising results made the country a pioneer in introducing and evaluating population-level interventions to help reduce alcohol-related harms.

Recent studies found societal inequalities among the potential causes of the incidence of substance-related harm (including alcohol) in a population. A possible explanation is that the disadvantaged socio-economic position, jointly with the constant comparison with those in more privileged positions and a general lack of opportunity may push individuals into mental health struggles and/or in a need to escape from reality and, consequently, more vulnerable to substance use disorders when exposed.

The legal nature of alcohol and its social acceptability made the number of individuals in Scotland misusing alcohol considerably higher compared to illegal drugs, with consequent greater associated mortality in the population. Summarising, both the lawful nature of alcohol consumption and the high incidence of AUD results in a need for policy specific approaches to tackle the phenomenon.

To design policies aimed at tackling alcohol-related harm and the inequality associated with its burden, a deep understanding of the epidemiology of alcohol-related harm is needed. In particular, acknowledging that the disadvantage and health inequality caused by excessive alcohol consumption is only a reflection of a deeper cause of inequality is crucial. The process which epidemiology informs the design of a policy could be simplified in three sequential and recurrent steps. Firstly, the epidemiology identifies trigger points as well as potential clinical and societal consequences in a theory of change which can inform policy makers on relationships to focus on to build an effective policy. Secondly, after the implementation of the policy, epidemiology (through both qualitative and quantitative investigations) can suggest the policy evaluation process highlighting the most appropriate outcomes and subpopulations to inquire. Lastly, based on the outcome of the evaluation, epidemiology can update the theory of change as well as recommend amendments to the policy to improve its efficacy. The succession of the first epidemiology assessment, policy implementation and policy evaluation is supposed to be a cyclical and iterative process, tending to the most efficient policy design.

The main body of this thesis are eight published articles on alcohol epidemiology. As articles were originally designed for different purposes, they are accompanied by an essay aimed to show the cohesion among them. In particular, the essay uses evidence from the published papers to describe the iterative process between epidemiology, policy implementation and evaluation using MUP, the most extensively analysed alcohol policy in Scotland, as a case study (three studies presented here regard MUP). The thesis also comments and discusses how MUP has been evaluated and the potential bias and sub-optimal communication between researchers and policy makers. The discussion on MUP evaluation refers mainly to the Public Health Scotland (PHS) report published in 2023, which was the main source for collecting the available evidence to inform the Scottish Government on whether to continue, suspend or reshape the policy.

Overall, the evidence shows that MUP is an effective policy in reducing alcohol consumption, but it affected the population differently and with divergences compared to what was originally theorised. While population groups with a higher incidence of alcohol-related harm are generally more affected by the policy (with a consequent reduction of health inequality), within such groups, evidence suggests that individuals with alcohol dependence were less affected. Moreover, there is evidence that most of the acute outcomes reflecting alcohol harm in societies theorised to be impacted (such as road traffic accidents and crime) were not affected. This underlines how specific societal outcomes or vulnerable subgroups need more targeted strategies and that one policy can benefit some but not everyone. Expected and unexpected results should be similarly communicated to put such complementary strategies into action. A potentially unbalanced communication of positive (expected) results to policy makers and the public opinions risk to create a sense of accomplishment and slow down a more comprehensive and structural policy action.

The publications of this thesis can be divided in two sections, each of them containing four studies. The first section named Clinical epidemiology of AUD, highlights some patterns in AUD patients (e.g., specificities of relapses and treatment). The second one, named Evaluation of public health policies on AUD is an assessment of certain policies (MUP and Covid lockdown) on specific outcomes. The explicatory essay, after a general introduction collocating studies under the same general context, uses evidence from the first section, together with other literature, to leverage the mechanisms of risk factors as a suggestion to complement MUP-like blanket policies that do not impact equally all those in need.