Insulin Requirement and Complications Associated With Serum C-Peptide Decline in Patients With Type 1 Diabetes Mellitus During 15 Years After Diagnosis

Abstract

ObjectiveC-peptide is conventionally used in assessing pancreatic function in patients with diabetes mellitus. The clinical significance of this molecule during the course of type 1 diabetes mellitus (T1DM) has been recently revisited. This study aimed to investigate the natural course of C-peptide in T1DM patients over the period of 15 years and analyze the association between the residual C-peptide and diabetes complications.MethodsThis retrospective study included a total of 234 children and adolescents with T1DM. Patient data including sex, age at diagnosis, anthropometric measures, daily insulin dose, serum HbA1c, post-prandial serum C-peptide levels, lipid profiles, and diabetic complications at the time of diagnosis and 1, 3, 5, 10, and 15 years after diagnosis were retrospectively collected.ResultsAmong the 234 patients, 101 were men and 133 were women, and the mean patient age at initial diagnosis was 8.3 years. Serum C-peptide decreased constantly since the initial diagnosis, and showed a significant decline at 3 years after diagnosis. At 15 years after diagnosis, only 26.2% of patients had detectable serum C-peptide levels. The subgroup with older patients and patients with higher BMI standard deviation score showed higher mean serum C-peptide, but the group-by-time results were not significant, respectively. Patients with higher serum C-peptide required lower doses of insulin and had fewer events of diabetic ketoacidosis.ConclusionSerum C-peptide decreased consistently since diagnosis of T1DM, showing a significant decline after 3 years. Patients with residual C-peptide required a lower dose of insulin and had a lower risk for diabetic ketoacidosis.

Preserved C-peptide is common and associated with higher time in range in Chinese type 1 diabetes

“…Further investigation of GAD autoantibody is clearly required. Meanwhile, our study suggested that residual b-cell function was associated with lower daily insulin dose, which was in line with previous studies (11,(20)(21)(22)(23). Because C-peptide levels represent intrinsic b-cell function ( 24), a possible explanation is that participants with higher C-peptide levels had more endogenous insulin production and required lower doses of exogenous insulin.…”

Hypoglycemic and antioxidant potency of ethyl acetate fraction of hydro-methanolic extract (60:40) of Tamarindus indica Linn. seed in streptozotocin-induced diabetic experimental animal

“…A number of physiological and biochemical changes take place due to insulin deficiency (Alam et al, 2021). Function of β cells can be monitored by assessments of serum insulin and C-peptide (Suh et al, 2022). In this study streptozotocin induced diabetic animals resulted in a significant diminution in serum insulin as well as C-peptide levels.…”

Use of a type 1 genetic risk score for classification of diabetes type in young Australian adults: the Fremantle Diabetes Study Phase II

“…The FDS2 participants in this substudy were diagnosed with a mean of approximately 20 years before recruitment. There is evidence from longitudinal studies in T1D that the serum C-peptide typically declines exponentially from diagnosis to low or undetectable concentrations at 15 years and beyond, 15 although there may be subgroups of patients in which there is a much slower, prolonged reduction. 16,17 Nevertheless, the very low fasting serum C-peptide concentrations in our participants with T1D are likely to have generated a higher AUC differentiating them from those with LADA/T2D than if the same analysis had been performed close to the time of diagnosis when the serum C-peptide concentrations were closer to those of the other diabetes types.…”