Epidemiological modelling and evaluation of alcohol policies in Hong Kong

Abstract

Alcohol consumption contributes to more than 5% of all global deaths annually, imposing significant social and economic costs. Over the years, alcohol consumption has been on the rise, and the trend has accelerated during the pandemic. In 2007-2008, Hong Kong, a special administrative region of China, reduced and eliminated tax on alcoholic beverages with less than 30% alcohol by volume, contrary to World Health Organization policy recommendations. Epidemiological, statistical, and economic analyses were applied to investigate the burden of the alcohol policies.

There was an increasing trend in alcohol sales and affordability in Hong Kong from 2004 to 2019 with a sharp increase following the alcohol tax reductions in 2007 to 2008. Carriers of a common genetic polymorphism of an enzyme for alcohol metabolism, inactivated aldehyde dehydrogenase (ALDH2*2), mostly found in East Asians, are at an increased risk of cancers of the upper aerodigestive tract, head and neck. The systematic review and meta-analysis on ALDH2*2 carriers and the increased risk of cancers provide better estimates of the current burden of alcohol. The derived dose-response curves were used in a simulation-based approach to estimate the population attributable fraction (PAF) of cancer incorporating the ALDH2*2 carriers in China, Japan, and South Korea. An accurate estimate of burden is essential to help reduce the health and economic burden from the harmful use of alcohol.

I applied interrupted time series models to assess the impact of the alcohol tax reduction on police reports of violent crime and sexual assault were used as a proxy for interpersonal violence and were supplemented by rates of hospitalizations due to assault. There were immediate and sustained increases in rates of hospitalizations due to assault in different age groups.

Similar methods were applied to investigate the impact of the policy on road traffic harm, however the Hong Kong government implemented road traffic policies to mitigate drink-driving. The timepoints of interest in the quasi-experimental study design on road traffic harm included the enactment dates of the alcohol tax policy and road safety policies that Hong Kong enacted to combat drink-driving. Despite weakened alcohol control and increased alcohol sales over the same period, road safety policies were able to mitigate a small aspect of alcohol-related harms due to the alcohol tax decrease.

To explore the potential of using pricing as a mitigating strategy, I applied econometric epidemiological modelling on consumption and health outcomes to estimate the additional burden of harm after the alcohol tax reductions and elimination in 2007 and 2008. Pricing and industry sales data were utilized to derive 25 price elasticity estimates. Internationally validated risk functions were applied to assess the impact on 25 alcohol-attributable conditions. These policy modelling tools were used to estimate the impact of the tax reversion at different pass-through rates. Reversion of the tax at all pass-through rates showed a reduction in alcohol-attributable burden.

Given the wide social harms of alcohol consumption, stronger actions such as reintroduction of taxes to reduce alcohol related burden of disease merits consideration to prevent avoidable harms.