Tobacco retail outlet restrictions: health and cost impacts from multistate life-table modelling in a national population.

BACKGROUND: Since there is some evidence that the density and distribution of tobacco retail outlets may influence smoking behaviours, we aimed to estimate the impacts of 4 tobacco outlet reduction interventions in a country with a smoke-free goal: New Zealand (NZ).

METHODS: A multistate life-table model of 16 tobacco-related diseases, using national data by sex, age and ethnicity, was used to estimate quality-adjusted life years (QALYs) gained and net costs over the remainder of the 2011 NZ population's lifetime. The outlet reduction interventions assumed that increased travel costs can be operationalised as equivalent to price increases in tobacco.

RESULTS: All 4 modelled interventions led to reductions of >89% of current tobacco outlets after the 10-year phase-in process. The most effective intervention limited sales to half of liquor stores (and nowhere else) at 129 000 QALYs gained over the lifetime of the population (95% UI: 74 100 to 212 000, undiscounted). The per capita QALY gains were up to 5 times greater for Māori (indigenous population) compared to non-Māori. All interventions were cost-saving to the health system, with the largest saving for the liquor store only intervention: US$1.23 billion (95% UI: $0.70 to $2.00 billion, undiscounted).

CONCLUSIONS: These tobacco outlet reductions reduced smoking prevalence, achieved health gains and saved health system costs. Effects would be larger if outlet reductions have additional spill-over effects (eg, smoking denormalisation). While these interventions were not as effective as tobacco tax increases (using the same model), these and other strategies could be combined to maximise health gain and to maximise cost-savings to the health system.