Propensity adjusted effects of environmental and socioeconomic biotope on the risk of coronary obstruction

Background/introduction: Several studies reported positive associations between long-term exposure to PM2.5, NO2, noise from road traffic and loss of residential green with coronary artery calcification score measurements, but their effects on coronary lumen reduction and flow impairment are still unknown. Purpose: To assess the independent impacts of environmental and socioeconomic exposures on the incidence of obstructive coronary artery disease (OCAD: at least one stenosis of >50% in any vessel), abnormal derived fractional flow reserve (FFRCT) and subsequent myocardial revascularization. Methods: 2619 consecutive patients screened by computed tomography angiography (CCTA) for stable chest pain between 01 January 2019 and 31 December 2020 were included. The last four years’ mean exposure to PM2.5 and NO2 were modelled using an interpolation method at the patient’s living address. Distances to main road, normalised difference vegetation index, educational level and annual incomes of the surroundings were also modelled. Low exposure (data below or equal to Q1) and high exposure (data above Q3) groups were defined and compared after a propensity score integrating the 13 known covariates affecting cardiovascular risk. Results: Mean exposure to PM2.5 and NO2 were 13.1 and 21.8 mg/m3, with all patients exposed to concentrations higher than the annual 2021 WHO standards. After propensity score matching, no environmental or socioeconomic factor was associated with the risk of OCAD or abnormal FFRCT. Myocardial revascularization risk was increased with PM2.5 exposure (RR:1.65; CI 95%:1.13–2.41) and annual income (RR:1.85; CI 95% 1.25–2.75), whereas myocardial revascularization risk was decreased with NDVI (RR: 0.59; CI 95% 0.41–0.86) and low educational level (RR:0.61; CI 95%:0.41–0.91). Conclusions: After adjusting for all known parameters associated with cardiovascular risk, the patients’ environment was not associated with coronary obstruction and subsequent ischaemia. Myocardial revascularisation rate was affected by both pollutant and socioeconomic environments, suggesting more advanced disease and/or difference in patient access to healthcare facilities.