Univariate weighted logistic regression and weighted multivariate logistic regression with adjustment for covariates (Models 1-3) were used to explore the risk of DR occurrence across different DM durations, as well as the synergistic effect of DM duration and anemia on DR occurrence.<h4>Results</h4>Weighted univariate logistic regression analysis revealed that insulin use, diabetic nephropathy (DN), and education level were significantly associated with DR across both DM duration groups. Here, INS is linked to anemia (phenotype).