Short-term exposure to gaseous pollutants is neglected factors for knee osteoarthritis: evidence from a humid subtropical region of China.

Few studies were performed on the impact of exposure to gaseous pollutants on the risk of knee osteoarthritis (KOA). We conducted this study to analyze the association between short-term exposure to gaseous pollutants and the risk of hospitalizations for KOA. A total of 2952 KOA hospitalizations derived from two hospitals in Hefei, and the relationship between gaseous pollutants and KOA hospitalizations was analyzed by a distributed lag non-linear model combined with a generalized linear model. We found that the decreased risk of hospitalizations for KOA were both related to exposure to NO2 (RR = 0.993, lag19 day) and O3 (RR = 0.984, lag0 day), while exposure to CO could increase the risk of hospitalizations for KOA (RR = 1.076, lag2 day). Stratified analyses suggested that the KOA patients < 65 years were more susceptible to O3 exposure, and the female, male, patients ≥ 65 years, and patients < 65 years were both more sensitive to CO exposure. Our findings demonstrated that exposure to NO2, O3 resulted in a decreased risk for KOA hospitalizations, and CO exposure might increase the risk of KOA hospitalizations.