Association of serum C peptide level with the severity of diabetic foot ulcers and its healing rate

Abstract

Objective To investigate the association of serum C peptide concentration with the severity and the outcome of diabetic foot ulcer(DFU). Methods The clinical data of 257 inpatients with DFU were collected, including fasting and postprandial 2h C peptide levels and C peptide area under curve(AUCCP). The patients were followed up on the outcomes of ulcers and death. The associations of serum C peptide concentration with the Wagner degree, infection severity, and healing rate were analyzed. Results The medians of fasting and 2h postprandial serum C peptide as well as AUCCP were 1.37(0.02~9.00)nmol/L, 3.22(0.02~29.61)nmol/L, and 511.65(3.60~2 691.30)nmol·min-1·L-1 respectively, which were lower than general levels. The time of follow-up in our study was 2.8(1.0~5.1)years. By the end of study, the wound of 75.88% patients was healed, 3.5% undergone major amputation, and 23.74% died. After adjusting for relative factors, there were no significant associations of serum fasting and postprandial C peptide levels and AUCCP with Wagner degree and infection severity(P>0.05). Cox regression analysis showed that the fasting plasma C peptide and hemoglobin were the independent protective factors for the healing of ulcers; old age, male, higher infection degree, and diabetes family history were their independent risk factors(all P<0.05). Conclusions The lower plasma fasting C peptide concentration in patients with DFU is not correlated with Wagner degree and infection severity, but closely related with healing rate. (Chin J Endocrinol Metab, 2017, 33: 17-22) Key words: Diabetic foot; Ulcers; Healing; C peptide