INS and diabetes mellitus: At the multivariable binary logistic regression analysis (Table 2), the univariable association with insulin use dissipated, whereas factors that were associated with DR independently were DM duration (multivariable OR = 3.16, 95% CI: 1.55–6.44, p = 0.002), HbA1c levels (multivariable OR = 2.94, 95% CI: 1.37–6.32, p = 0.006), and the presence of neuropathy (multivariable OR = 3.59, 95% CI: 1.43–9.05, p = 0.007).