China Pharmaraceutical University, China (People's Republic)
Background: Postoperative acute kidney injury (AKI) is a significant complication following major surgeries, associated with increased morbidity, prolonged hospital stays, and higher healthcare costs. While air pollution has been linked to various systemic diseases, its impact on postoperative renal outcomes remains unclear. This study aims to investigate the association between exposure to air pollutants, including PM2.5, NO₂, O₃, and the Air Quality Health Index (AQHI), and the incidence of postoperative AKI, AKI stage 2+ (AKI 2+), and acute kidney disease (AKD) in a large multicenter surgical cohort.
Objectives: This study investigates the association between air pollution exposure (PM2.5, NO₂, O₃, AQHI) and postoperative AKI, AKI 2+, and AKD in surgical patients. We assess both long-term (365-day) and short-term (30-day) exposure and examine the impact of AQHI on the time to AKI onset. Findings aim to inform perioperative risk stratification and air quality management to reduce postoperative renal complications.
Methods: This multicenter cohort study analyzed 268,867 surgical patients (2015–2023) across three Chinese medical centers. Air pollution exposure (PM2.5, NO₂, O₃, AQHI) was assessed for short-term (30 days) and long-term (365 days) periods. Primary outcome: postoperative AKI (KDIGO criteria); secondary outcomes: AKI 2+ and AKD. Logistic regression estimated odds ratios (OR/aOR) for renal outcomes, while generalized linear models examined AQHI’s impact on AKI onset time.
Results: Long-term exposure to higher PM2.5 and AQHI levels significantly increased the risk of AKI, AKI 2+, and AKD. PM2.5 (per unit increase): AKI (aOR = 1.04, 95% CI: 1.03–1.05), AKI 2+ (aOR = 1.03, 95% CI: 1.02–1.04), AKD (aOR = 1.10, 95% CI: 1.09–1.12). AQHI (per unit increase): AKI (aOR = 2.13, 95% CI: 1.64–2.76), AKI 2+ (aOR = 2.32, 95% CI: 1.53–3.49), AKD (aOR = 8.46, 95% CI: 4.68–15.21). Short-term PM2.5 and NO₂ exposure also increased AKI, AKI 2+ risk, but associations were weaker. O₃ exposure was linked to a lower AKI/AKD risk (aOR < 1.00, p < 0.05). Higher AQHI levels correlated with shorter AKI onset time (β = 1.74, SE = 0.09, p < 0.001). Older (≥60 years), male, and cardiac surgery patients showed stronger associations, with seasonal variations.
Conclusions: This study confirms that high PM2.5 and AQHI exposure significantly increases the risk of postoperative AKI, AKI 2+, and AKD. These findings underscore the need for preoperative risk assessment and air quality management to mitigate renal risks. Further research should explore underlying mechanisms and intervention strategies.
