Clinical impact of air pollution on SPECT myocardial perfusion imaging

Air pollution contributes to cardiovascular morbimortality. Air pollution effects on cardiovascular function assessed from non-invasive and invasive imaging have been reported but never on myocardial perfusion. This study aimed to characterize relations of air pollution exposure to myocardial perfusion imaging (MPI).

Patients referred to SPECT (single-photon emission computed tomography) MPI were prospectively enrolled between 2017 and 2020. Myocardial ischemia was assessed from the SPECT. Moderate-to-severe ischemia was defined as a > 10 % ischemic myocardium. Exposures to particulate matter (PM_2.5 and PM₁₀) and NO₂ at the home address were characterized via a 10-meter resolution air pollutant-dispersion model and air quality monitoring system data. Associations of exposures with scintigraphy parameters were assessed through multivariable regressions, and potential modifying effects by sex and BMI were investigated.

A total of 1,585 participants were prospectively included (mean age 67.7 ± 11.6 years, 63.3 % male); 148 (9.3 %) patients presented a moderate-to-severe ischemia. In multivariate analysis, the odds of moderate-to-severe ischemia was increased, with adjusted odds-ratio (ORa) of 1.39 [95 % confidence interval (95 % CI): 1.07-1.80; p = 0.013], 1.33 (95 % CI: 1.01-1.75; p = 0.042), and 1.22 (95 % CI: 0.96-1.57; p = 0.10) for each increase of one Interquartile Range (IQR) in PM_2.5, PM₁₀ and NO₂ exposure, respectively (IQR equal to 3.3, 4.3 and 10.0 µg/m³, respectively). With further adjustment for cardiometabolic diseases and symptoms, only the association with PM_2.5 remained statistically significant: ORa 1.34 (95 % CI: 1.03-1.75, p = 0.031) for each one-IQR increase. Associations with PM₁₀ and PM_2.5 tended to be stronger in women (interaction p-value equal to 0.11 and 0.077, respectively).

We provide new insights into a mechanism by which particulate air pollution may influence cardiovascular risk. Exposure to PM was associated with moderate-to-severe ischemia, particularly in women.