Ann Pediatr Endocrinol Metab.  2020 Mar;25(1):38-41. 10.6065/apem.2020.25.1.38.

Comparison of proinsulin to C-peptide ratio in children with and without type 1 diabetes and its relation to age

• Ellison BR
• Burton JH
• Hsia DS

• KMID: 2501035
• DOI: http://doi.org/10.6065/apem.2020.25.1.38

Abstract

Purpose
This study aimed to compare the proinsulin to C-peptide (PI:C) ratio in those with recent-onset type 1 diabetes versus those with no diabetes and to explore the effect of age on PI:C ratio.
Methods
Nineteen participants (n=9 with type 1 diabetes and n=10 with no diabetes) between 10 and 19 years of age were enrolled in a single-visit cross-sectional study and underwent blood collection after 10 hours fasting to measure proinsulin and C-peptide levels as well as other glycemic parameters.
Results
The median PI:C ratio was significantly different between type 1 diabetes and nondiabetes groups (6.24% vs. 1.46%, P<0.01). A significant negative correlation was seen between PI:C ratio and patient age after adjustment for duration of diabetes (r²=0.61, P=0.02) in the type 1 diabetes group.
Conclusion
Even in this narrow age window, a higher degree of β-cell dysfunction indicated by a higher PI:C ratio was seen in younger children.

Keyword

Proinsulin; C-peptide; Type 1 diabetes mellitus; Biomarkers

Figure

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  Fig. 1. A significant negative correlation was observed between PI:C ratio and age. PI:C, proinsulin to C-peptide.

Reference

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