Tobacco endgame intervention impacts on health gains and Māori:non-Māori health inequity: a simulation study of the Aotearoa-New Zealand Tobacco Action Plan

Objective To estimate the health gains and Māori:non-Māori health inequality reductions of the Aotearoa/New Zealand Government’s proposed endgame strategy. Design Simulation modelling: a Markov model to estimate future yearly smoking and vaping prevalence (for business-as-usual [BAU] and intervention scenarios) linked to a proportional multistate lifetable model with 16 tobacco-related diseases to estimate future morbidity and mortality rates, and health adjusted life years (HALYs). Setting Aotearoa. Participants Population alive in 2020 (5.08 million) simulated over the rest of their lifespan. Interventions 1. Denicotinisation of all retail tobacco in 2023, 2. 1 plus media promotion, 3. 95% reduction in tobacco retail outlets in 2023, 4. a tobacco free-generation whereby people born in 2006 and later are never legally able to purchase tobacco, 5. combined package of 2, 3 and 4. Main Outcome Measures Future smoking prevalence, deaths averted and HALYs by sex and ethnic group. Percent reduction in Māori:non-Māori all-cause mortality rate difference in 2040 under interventions compared to business as usual (BAU). Results The combined package of strategies was estimated to reduce adult smoking prevalence from 31.8% in 2022 to 7.3% in 2025 for Māori, and 11.8% to 2.7% for non-Māori. The 5% smoking prevalence target was forecast to be achieved in 2026 and 2027 for Māori males and females, respectively. The HALY gains for the combined package (compared to BAU) over the population’s remaining lifespan was estimated to be 594,000 (95%UI: 443,000 to 738,000; 3% discount rate). The denicotinisation strategy alone achieved 97% of these HALYs, the retail strategy 19%, and tobacco-free generation 12%. The future per capita HALY gains for the combined package for Māori were estimated to be 4.75 and 2.14 times higher than for non-Māori females and males, respectively. The absolute difference between Māori and non-Māori all-cause mortality for 45+ year olds in 2040 was estimated to be 23.4% (19.1% to 27.6%) less for females under the combined package compared to BAU, and 9.5% (7.5% to 11.3%) less for males. Conclusion A tobacco endgame strategy, especially denicotinisation, could dramatically reduce health inequities. Funding New Zealand Ministry of Health. Summary boxes What is already known on this topic Modelling of health gains and health inequality reductions for some tobacco endgame strategies has been undertaken internationally, and specifically in Aotearoa (tobacco free generation policy, substantial reductions in the number of tobacco outlets including, a sinking lid that gradually phased out all tobacco supply between 2011 to 2025, restricting tobacco sales to pharmacies only with brief cessation advice provided to consumers). All modelling suggested that these interventions improved equity, of varying magnitude, in either smoking prevalence or health gain for Māori compared to non-Māori. Endgame modelling of denicotinisation has not been undertaken, alone or in combination with other interventions. The interplay of tobacco smoking and vaping has not been explicitly included in endgame modelling. The package of endgame strategies in the Aotearoa-New Zealand Government’s Smokefree Action Plan (Dec 2021) have not been modelled. What this study adds The Government’s package (denicotinisation of retail tobacco, 95% reduction in the number of tobacco retail outlets; and a tobacco-free generation) if implemented in 2023 is forecast to achieve less than 5% smoking prevalence by 2025 for non-Māori, and by 2027 for Māori. Denicotinisation is estimated to achieve the majority of the health gains. A 95% retail outlet reduction and a tobacco-free generation, on their own, are unlikely to achieve a 5% smoking prevalence for any sex by ethnic groups until at least 2040. The combined package, compared to BAU, is estimated to reduce the Māori:non-Māori gap in 45+ year old all-cause mortality in 2040 by 22.9% (95% uncertainty interval 19.9% to 26.2%) for females and 9.6% (8.4% to 11.0%) males.