Air pollution indicators could significantly improve the predictive performance of the basic clinical model (model 1, including sex, age of DM onset, duration of DM, hyperlipidemia, the treatment of lipid-lowering drugs, smoking status, insulin treatment, HF, baseline eGFR, MAP, BMI, anemia, urinary protein, and serum ALB), except for PM2.5 (0.850 vs. 0.840, P > 0.05, Fig. 6G). Here, ALB is linked to anemia.