Mixed-meal tolerance test to assess residual beta-cell secretion: Beyond the area-under-curve of plasma C-peptide concentration.
Ontology highlight
ABSTRACT: Aims
Residual beta-cell secretion in type 1 diabetes is commonly assessed by area-under-curve of plasma C-peptide concentration (AUCCpep ) following mixed-meal tolerance test (MMTT). We aimed to investigate alternative measures of beta-cell responsiveness.Methods
We analyzed data from 32 youth (age 7 to 17 years) undergoing MMTT within 6 months of type 1 diabetes diagnosis. We related AUCCpep with (a) validated mechanistic index of postprandial beta-cell responsiveness MI accounting for glucose level during MMTT, and (b) pragmatic marker calculated as baseline plasma C-peptide concentration corrected for baseline plasma glucose concentration.Results
Postprandial responsiveness MI was correlated with age and BMI SDS (Rs = 0.66 and 0.44, P < 0.01 and P < 0.05) and was more correlated with glycated hemoglobin than AUCCpep (Rs = 0.79, P = 0.04). The pragmatic marker was highly correlated with AUCCpep (Rs = 0.94, P < 0.01).Conclusions
Postprandial responsiveness MI may be more relevant to glucose control than AUCCpep . Baseline C-peptide corrected for baseline glucose appears to be a suitable surrogate of AUCCpep if MMTT is not performed.
SUBMITTER: Ruan Y
PROVIDER: S-EPMC6487945 | biostudies-literature |
REPOSITORIES: biostudies-literature
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