Do dual purchasers behave differently? An analysis of purchasing data for households that buy both alcohol and tobacco in the United Kingdom.

Background And Aims: Dual purchasers of alcohol and tobacco are at increased health risk from the interacting health impacts of alcohol and tobacco use. They are also at financial risk from exposure to the dual financial cost of policies that increase alcohol and tobacco prices. Understanding whose alcohol and tobacco use exposes them to these health and financial risks is important for understanding the inequality impacts of control policies. This study explores the extent to which household spending on alcohol and tobacco combined varies between socio-economic groups and compares this with results for households which purchase only one of the commodities.

Design: Cross-sectional analysis of household-level alcohol and tobacco purchasing data.

Setting: United Kingdom, 2012-17.

Participants/cases: A total of 26 021 households.

Measurements: We analysed transaction-level data from individual 14-day spending diaries in the Living Cost and Food Survey (LCFS). We used this to calculate expenditure, volumes of alcohol and tobacco purchased, and the price paid per unit of alcohol (1 unit = 8 g) and per stick of tobacco. This was compared with equivalized total expenditure and quintiles of equivalized household income. Prices were calibrated and pack sizes were imputed using empirical sales data from Nielsen/CGA to correct for reporting bias.

Findings: Dual purchasing households spent [95% confidence interval] more on alcohol and more on tobacco than their single-purchasing counterparts. In general, lower-income households spent less on both alcohol and tobacco than higher-income households. Furthermore, dual purchasing households in the lowest income group were most exposed to potential increases in price than were other income groups, with (CI = 12.41-13.15%) of their total household budget spent on alcohol and tobacco.

Conclusions: Dual purchasers of alcohol and tobacco in the United Kingdom appear to be concentrated evenly among income groups. However, dual purchasers may experience particularly large effects from pricing policies, as they spend a substantially higher proportion of their overall household expenditure on alcohol and tobacco than do households that purchase only one of the commodities.