Preoperative Exposure to Fine Particulate Matter and Risk of Postoperative Complications: A Single Center...

While exposure to fine particulate matter air pollution (PM _2.5 ) is known to cause adverse health effects, its impact on postoperative outcomes in US adults remains understudied. Perioperative exposure to PM _2.5 may induce inflammation that interacts insidiously with the surgical stress response, leading to higher postoperative complications.

We conducted a single center, retrospective cohort study using data from 49,615 surgical patients living along Utah's Wasatch Front and who underwent elective surgical procedures at a single academic medical center from 2016-2018. Patients' addresses were geocoded and linked to daily Census-tract level PM _2.5 estimates. We hypothesized that elevated PM _2.5 concentrations in the week prior to surgery would be associated with an increase in a bundle of major postoperative complications. A hierarchical Bayesians regression model was fit adjusting for age, sex, season, neighborhood disadvantage, and the Elixhauser index of comorbidities.

Postoperative complications increased in a dose-dependent manner with higher concentrations of PM _2.5 exposure, with a relative increase of 8% in the odds of complications (OR=1.082) for every 10ug/m ³ increase in the highest single-day 24-hr PM _2.5 exposure during the 7 days prior to surgery. For a 30 fold increase in PM _2.5 (1 ug/m ³ to 30ug/m ³ ) the odds of complication rose to over 27% (95%CI: 4%-55%). The association persisted after controlling for comorbidities and confounders; our inferences were robust to modeling choices and sensitivity analysis.

In this large Utah cohort, exposure to elevated PM _2.5 concentrations in the week before surgery was associated with a dose-dependent increase in postoperative complications, suggesting a potential impact of air pollution on surgical outcomes. These findings merit replication in larger datasets to identify populations at risk and define the interaction and impact of different pollutants. PM _2.5 exposure is a potential perioperative risk factor and, given the unmitigated air pollution in urban areas, a global health concern.