INS and diabetic retinopathy: By comparing the general data and disease related data of the elderly diabetes high-risk foot group and the elderly diabetes low-risk foot group, it is found by t-test or chi square test that there are statistically significant differences between the two groups in terms of age, diabetes course, glycosylated hemoglobin (HbA1c), blood glucose treatment methods (insulin injection group and non insulin injection group), diabetes retinopathy, hyperlipidemia, cerebrovascular surgery history, cardiovascular surgery history, etc. (P < 0.05), see Table 1 for details.