The distributional and financial impacts of the soft drinks industry levy on childhood dental caries in England

Background

Untreated dental caries is the most prevalent condition worldwide, affecting 2.3 billion people across all ages (26.2%) and 250 million children under 5-years (37.6%). In England, 10.7% of 3-year-olds and 23.7% of 5-year-olds have the condition. Childhood caries is more common in low-income families, deprived areas and ethnic minority groups. It is also the most common reason for children to be admitted to hospitals in England, mostly for dental extractions under general anaesthesia.

Sugar-sweetened beverages (SSBs) are one of the largest sources of sugars in the diet and a major risk factor for childhood caries. Policies to curb the intake of SSBs can help reduce the high prevalence of untreated caries, especially among socially disadvantaged groups. The UK government announced a soft drinks industry levy (SDIL) in March 2016, which came into effect in April 2018.

Aim and objectives

The aim of this proposal is to evaluate the impact of the SDIL on social inequalities in severe dental caries among children in England and resulting financial outcomes. This is an important question as opponents of the tax argue it is regressive (i.e., poor people will pay more taxes as a proportion of their income) and could therefore affect the poor more. Such an evaluation can provide valuable information to other governments considering a new tax or revising an existing one.

The objectives of this project are:

1) To evaluate the impact of the SDIL on absolute and relative inequalities in hospital admissions for caries-related extractions according to deprivation, ethnicity and urbanicity.

2) To evaluate the distributional consequences of the SDIL in terms of both financial and health outcomes through an extended cost-effectiveness analysis (ECEA). Methods

This proposal will use routine administrative data on hospital admissions for caries-related extractions among children under 18-years in England. Admissions for dental extractions are a robust indicator that captures the most severe end of the distribution of dental caries in the population.

Monthly data from January 2008 to June 2024 will be used, including over 10-years before the SDIL was announced, around 2-years between the date the SDIL was announced and enforced (implementation period) and over 6-years after it was enforced. Data on hospital admissions will be requested from NHS Digital for a fee. We will compare socioeconomic, ethnic and geographical differences in admissions for dental extractions before, during and after the implementation periods for all child patients and for different age groups (0-4, 5-9, 10-14 and 15-17-years).

The ECEA will evaluate both the health and financial consequences of the SDIL on three domains: health gains (reductions in childhood obesity and dental caries rates), financial benefits and the distributional impact across social groups. The findings of this proposal and those from published studies will inform the economic evaluation.

Timeline for delivery The project will be completed in 15 months. Anticipated impact and dissemination

Findings will be disseminated via multiple strategies, such as commentaries and viewpoints in media outlets and Queen Mary’s website, established professional networks, and engaging with WHO Collaborating Centres internationally. We anticipate that the findings will inform updates of the government’s obesity strategy and reaching target 2.1 of the WHO global oral health action plan.