FRIDAY, May 22, 2026 (HealthDay News) -- Preoperative fine particulate matter (PM2.5) exposure is associated with an increased risk for postoperative complications, according to a study published online April 26 in Acta Anaesthesiologica Scandinavica.John F. Pearson, M.D., from the University of Utah School of Medicine in Salt Lake City, and colleagues conducted a single-center, retrospective cohort study using data from 49,615 surgical patients who underwent elective surgical procedures from 2016 to 2018 to examine air pollution as a potential perioperative risk factor. Patients' addresses were geocoded and linked to daily PM2.5 estimates at the Census-tract level. The binary outcome was a composite of postoperative pneumonia, surgical site infection, urinary tract infection, sepsis, stroke, myocardial infarction, or thromboembolic event. Adjusting for age, sex, season, neighborhood disadvantage, and the Elixhauser index of comorbidities, a hierarchical Bayesian regression model with weakly informative priors was used.The researchers found a dose-dependent association for postoperative complications with higher concentrations of PM2.5 exposure. For every 10 µg/m3 increase in the highest single-day 24-hour PM2.5 exposure during the seven days prior to surgery, there was a relative increase of 8.2 percent in the odds of complications (odds ratio, 1.082). The odds of complications increased to more than 27 percent for an increase in PM2.5 from 1 to 30 µg/m3. Across prior choices and model specifications, the results were robust."When there was an elevation in PM2.5 air pollution in the week before surgery, even for one day, we saw increased risk of major medical complications and infectious complications," Pearson said in a statement.Abstract/Full Text.Sign up for our weekly HealthDay newsletter