Benefits of hypothetical air pollution reduction interventions on NCDs in Belgium

Abstract Background The adverse health impact of air pollution on non-communicable diseases (NCDs) is well documented, yet methodological tools for assessing the potential health benefits of interventions are lacking. This study uses a parametric g-computation approach to evaluate the impact of hypothetical interventions targeting long-term air pollution exposure on reducing NCDs prevalence in Belgium, using data from three national Health Interview Surveys (BHIS 2008-2013-2018). Methods BHIS data (n = 27,536) were linked to environmental data at participants’ residential addresses. A g-computation approach was used to calculate the potential impact fractions of air quality interventions on several NCDs. Regression models were adjusted for socio-economic, environmental and lifestyle factors. The scenarios involved reducing individual long-term air pollution exposure to WHO air quality guideline levels, followed by investigating dose-response functions through various percentage reductions in air pollution exposure. Results Significant associations were found between air pollution and asthma, stroke, and multimorbidity. Adhering to WHO air quality guidelines would substantially reduce stroke risk in Belgium by 0.87% (95% CI:0.38; 1.35) for PM2.5 and 0.32% (95% CI:-0.05; 0.70) for NO2, preventing 63% and 22% of cases, respectively. For asthma, risk reduction was 1.43% (95% CI:-0.53; 3.4) for PM2.5 and 0.83% (95% CI: 0.01; 1.63) for NO2, preventing 27% and 16% of cases, respectively. For multimorbidity, risk reduction was 3.20 % (95% CI: -1.75; 8.16) for PM2.5 and 0.43% (95% CI:-2.03; 2.90) for NO2, preventing 7% and 0.4% of cases, respectively. Results revealed a clear dose-response association between air pollution reduction and the prevalence of stroke, asthma, and multimorbidity in Belgium. Conclusions This study demonstrates that air pollution reduction interventions could effectively decrease the prevalence of asthma, stroke, and multimorbidity in Belgium. Key messages • Air pollution reduction interventions could effectively decrease the prevalence of asthma, stroke, and multimorbidity in Belgium. • The g-computation approach to assess PIF of interventions represents a straightforward approach for drawing causal inferences from observational data.