Short-Term Effects of NO₂ Exposure on Hospitalization for Chronic Kidney Disease

This study investigates the correlation between short-term exposure to nitrogen dioxide (NO₂) and hospitalization for chronic kidney disease (CKD) in Lanzhou, China. A distributed lag nonlinear model (DLNM) was employed to examine the relationship between changes in NO₂ concentration and CKD hospitalizations. Subgroup analyses were conducted to assess the sensitivity of different populations to NO₂ exposure. A total of 35,857 CKD hospitalizations occurred from 1 January 2014 to 31 December 2019. The average daily concentration of NO₂ was 47.33 ± 17.27 µg/m³. A significant exposure response relationship was observed between changes in NO₂ concentration and the relative risk (RR) of CKD hospitalization. At lag0 (the same day) and lag0-1 (cumulative same day and the previous 1 day) to lag0-4 (cumulative same day and the previous 4 days), NO₂ exhibited a harmful effect on CKD hospitalizations, with the maximum effect occurring at lag0-1. For every 10 µg/m³ increase in NO₂ concentration, the RR of CKD hospitalization was 1.034 [95% confidence interval (CI): 1.017, 1.050]. Subgroup analyses revealed that the adverse effects of NO₂ were more pronounced in females and individuals aged ≥65 years. The harmful effects were also more significant during the cold season. In conclusion, short-term NO₂ exposure is associated with an increased relative risk of CKD hospitalization. Continuous efforts to improve air quality are essential to protect public health.