Dataset Information

Lessons from the mixed-meal tolerance test: use of 90-minute and fasting C-peptide in pediatric diabetes.

ABSTRACT:

Objective

Mixed-meal tolerance test (MMTT) area under the curve C-peptide (AUC CP) is the gold-standard measure of endogenous insulin secretion in type 1 diabetes but is intensive and invasive to perform. The 90-min MMTT-stimulated CP ?0.2 nmol/L (90CP) is related to improved clinical outcomes, and CP ?0.1 nmol/L is the equivalent fasting measure (FCP). We assessed whether 90CP or FCP are alternatives to a full MMTT.

Research design and methods

CP was measured during 1,334 MMTTs in 421 type 1 diabetes patients aged <18 years at 3, 9, 18, 48, and 72 months duration. We assessed: 1) correlation between mean AUC CP and 90CP or FCP; 2) sensitivity and specificity of 90CP ?0.2 nmol/L and FCP ? 0.1 nmol/L to detect peak CP ?0.2 nmol/L and the equivalent AUC CP; and 3) how the time taken to reach the CP peak varied with age of diagnosis and diabetes duration.

Results

AUC CP was highly correlated to 90CP (r(s) = 0.96; P < 0.0001) and strongly correlated to FCP (r(s) = 0.84; P < 0.0001). AUC CP ?23 nmol/L/150 min was the equivalent cutoff for peak CP ?0.2 nmol/L (98% sensitivity/97% specificity). A 90CP ?0.2 nmol/L correctly classified 96% patients using AUC or peak CP, whereas FCP ?0.1 nmol/L classified 83 and 85% patients, respectively. There was only a small difference seen between peak and 90CP (median 0.02 nmol/L). The CP peak occurred earlier in patients with longer diabetes duration (6.1 min each 1-year increase in duration) and younger age (2.5 min each 1-year increase).

Conclusions

90CP is a highly sensitive and specific measure of AUC and peak CP in children and adolescents with type 1 diabetes and offers a practical alternative to a full MMTT.

SUBMITTER: Besser RE

PROVIDER: S-EPMC3554273 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Lessons from the mixed-meal tolerance test: use of 90-minute and fasting C-peptide in pediatric diabetes.

Besser Rachel E J RE Shields Beverley M BM Casas Rosaura R Hattersley Andrew T AT Ludvigsson Johnny J

Diabetes care 20121030 2

<h4>Objective</h4>Mixed-meal tolerance test (MMTT) area under the curve C-peptide (AUC CP) is the gold-standard measure of endogenous insulin secretion in type 1 diabetes but is intensive and invasive to perform. The 90-min MMTT-stimulated CP ≥0.2 nmol/L (90CP) is related to improved clinical outcomes, and CP ≥0.1 nmol/L is the equivalent fasting measure (FCP). We assessed whether 90CP or FCP are alternatives to a full MMTT.<h4>Research design and methods</h4>CP was measured during 1,334 MMTTs i ...[more]

PMID: 23111058

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Dataset Information

Lessons from the mixed-meal tolerance test: use of 90-minute and fasting C-peptide in pediatric diabetes.

Objective

Research design and methods

Results

Conclusions

Publications

Lessons from the mixed-meal tolerance test: use of 90-minute and fasting C-peptide in pediatric diabetes.

Similar Datasets

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