Assessing the benefits of hypothetical air pollution reduction interventions on stroke in Belgium

Abstract Background The adverse health impact of air pollution exposure on stroke is already well documented but there is a lack of methodological tools to provide actionable evidence on the potential health benefits of realistic interventions. This study demonstrates the use of a parametric g-computation approach to evaluate the impact of hypothetical interventions targeting long-term exposure to air pollution on reducing the stroke prevalence in Belgium using data from three national Health Interview surveys (BHIS 2008-2013-2018). Methods BHIS data (n = 27536) were linked to environmental data of the participant's residential address. A g-computation approach was used to calculate the potential impact fractions of five air pollution reduction interventions to decrease the prevalence of stroke. Regression models were adjusted for socio-economic, environmental and lifestyle factors. In the first and second scenario, the average annual exposure to PM2.5 was lowered to the WHO guideline (5 μg/m3) and reduced by 25%, respectively. In the third and fourth scenario, the average annual exposure to NO2 was lowered to the WHO guideline (10 μg/m3) and reduced by 25%, respectively. In the last scenario, the average annual exposure to BC was reduced by 25%. Results Stroke was significantly associated with all air pollutants. A reduction in the risk of stroke was observed under the five scenarios: -0.87% [SE:0.24], -0.47% [SE: 0.17], -0.32% [SE: 0.19], -0.16% [SE:0.10], -0.13 % [SE: 0.07]. The proportion of prevented stroke cases would be respectively of 65.5%, 35.4%, 23.9%, 12.3%, 10%. Conclusions This study highlights the importance of air pollution on the stroke burden and demonstrates that air pollution reduction interventions could decrease the prevalence of stroke in Belgium. Key messages • Air pollution reduction interventions could significantly decrease the prevalence of stroke in Belgium. • Major benefits were observed for interventions targeting long-term exposure to PM2.5.