Clinical Edge

Summaries of Must-Read Clinical Literature, Guidelines, and FDA Actions

Proinsulin Secretion Persistent in Type 1 Diabetes

Diabetes Care; ePub 2018 Dec 10; Sims, et al

In individuals with long-duration type 1 diabetes (T1D), the ability to secrete proinsulin persists, even in those with undetectable serum C-peptide, according to a recent study. C-peptide and proinsulin were measured in fasting and stimulated sera from 319 subjects with long-standing T1D (≥3 years) and 12 control subjects without diabetes. Researchers considered 3 categories of stimulated C-peptide: 1) C-peptide positive, with high stimulated values ≥0.2 nmol/L; 2) C-peptide positive, with low stimulated values ≥0.017 but <0.2 nmol/L; and 3) C-peptide <0.017 nmol/L. Longitudinal samples were analyzed from C-peptide–positive subjects with diabetes after 1, 2, and 4 years. They found:

  • Of individuals with long-standing T1D, 95.9% had detectable serum proinsulin (>3.1 pmol/L), while 89.9% of participants with stimulated C-peptide values below the limit of detection (<0.017 nmol/L; n=99) had measurable proinsulin.
  • Proinsulin levels remained stable over 4 years of follow-up, while C-peptide decreased slowly during longitudinal analysis.
  • Correlations between proinsulin with C-peptide and mixed-meal stimulation of proinsulin were found only in subjects with high stimulated C-peptide values (≥0.2 nmol/L).
Citation:

Sims EK, Bahnson HT, Nyalwidhe J, et al. Proinsulin secretion is persistent feature of type 1 diabetes. [Published online ahead of print December 10, 2018]. Diabetes Care. doi:10.2337/dc17-2625.

This Week's Must Reads

National Trends: Thyrotoxicosis and Thyroid Storm, Thyroid; ePub 2018 Dec 18; Galindo, Hurtado, et al

Pancreas Volume is Decreased After T1D Onset, Diabetes Care; ePub 2018 Dec 14; Virostko, et al

PCOS Phenotype in Adolescence Not Linked to BMI, Fertil Steril; ePub 2018 Dec 6; Zore, Lizneva, et al

Air Pollutants, Spontaneous Pregnancy Loss Linked, Fertil Steril; ePub 2018 Dec 4; Leiser, Hanson, et al

Proinsulin Secretion Persistent in Type 1 Diabetes, Diabetes Care; ePub 2018 Dec 10; Sims, et al

Must Reads in Diabetes

Pancreas Volume is Decreased After T1D Onset, Diabetes Care; ePub 2018 Dec 14; Virostko, et al

Proinsulin Secretion Persistent in Type 1 Diabetes, Diabetes Care; ePub 2018 Dec 10; Sims, et al

Cerebrovascular Origin for Depression in T1D?, Diabet Med; ePub 2018 Dec 15; Nunley, et al

Quality of Life and T2D in Women Examined, Diabet Med; ePub 2018 Dec 15; Danhauer, et al

Cost-Related Insulin Underuse Evaluated, JAMA Intern Med; ePub 2018 Dec 3; Herkert, et al