INS and diabetes mellitus: As of 2019, among non-elderly group, male gender (84.4% vs. 60.2%, p=0.007), body weight (75.9 ± 12.7 kg vs. 69.3 ± 14.1 kg, p=0.011), waist circumference (93.9 ± 9.5 cm vs. 89.7 ± 11.0 cm, p=0.038), HbA1C (7.8 ± 0.8% vs. 7.4 ± 0.9%, p=0.016), duration of diabetes (22.8 ± 7.7 years vs. 19.7 ± 6.1 years, p=0.009), number of insulin used (0.8 vs. 0.6, p=0.008) and serum creatinine (1.5 ± 1.2 mg/dL vs. 1.0 ± 0.8 mg/dL, p= 0.041) were significantly higher in patients with incident DPN than in those without incident DPN.