Individualised tobacco affordability in the UK 2002–2014: findings from the International Tobacco Control Policy Evaluation Project

OBJECTIVE: The existing measures of tobacco affordability (smokers' purchasing power for tobacco) use national estimates of income and average cigarette prices, and exclude roll-your-own (RYO) tobacco. This study developed an individualised measure of tobacco affordability using smokers' own incomes and factory-made (FM) or RYO tobacco purchase prices, and explored how it was impacted by taxation changes, individual characteristics and purchase patterns. DESIGN: Cross-sectional survey data collated from 10 waves of a longitudinal cohort study. DATA SOURCES: Adult smokers (n=4062) from the International Tobacco Control Policy Evaluation Project United Kingdom (UK), surveyed between 2002 and 2014, providing 8943 observations over 10 surveys. ANALYSIS: Affordability was calculated as the percentage of annual income remaining with the individuals after their annual tobacco expenditure. Multilevel linear regression models were used with affordability as the outcome using time, sex, age, geographical region, ethnicity, education, nicotine dependence and tobacco purchase source as the predictor variables. RESULTS: Affordability of FM cigarettes decreased significantly from 91.5% (±95% CI: 91.0% to 91.9%) in 2002 to 87.8% (87.0% to 88.5%) in 2014; and RYO from 96.3% (95.7% to 96.9%) in 2006 to 93.7% (93.0% to 94.4%) in 2014. Affordability was significantly lower for FM than RYO. Year-on-year decreases were not statistically significant. Tobacco was more affordable for males, those with higher education, less dependent smokers and those purchasing from non-store (potentially illicit) or non-UK sources. CONCLUSIONS: An individualised measure of tobacco affordability provided useful insights on the impact of tobacco taxes, social inequalities and purchase patterns in the UK. Although tobacco became less affordable, the annual rate of decline was low, suggesting annual tax rises were not large enough.