Patterns of metabolic progression to type 1 diabetes in the Diabetes Prevention Trial–Type 1
JM Sosenko, JP Palmer, CJ Greenbaum… - Diabetes …, 2006 - Am Diabetes Assoc
JM Sosenko, JP Palmer, CJ Greenbaum, J Mahon, C Cowie, JP Krischer, HP Chase…
Diabetes care, 2006•Am Diabetes AssocOBJECTIVE—There is little information regarding the pattern of metabolic deterioration
before the onset of type 1 diabetes. The goal of this study was to utilize data from the
Diabetes Prevention Trial–Type 1 (DPT-1) to obtain a picture of the metabolic progression to
type 1 diabetes over a period of approximately 2.5 years before its diagnosis. RESEARCH
DESIGN AND METHODS—Fifty-four DPT-1 participants (22 in the parenteral trial and 32 in
the oral trial) were studied. All had oral glucose tolerance tests (OGTTs) at 6-month intervals …
before the onset of type 1 diabetes. The goal of this study was to utilize data from the
Diabetes Prevention Trial–Type 1 (DPT-1) to obtain a picture of the metabolic progression to
type 1 diabetes over a period of approximately 2.5 years before its diagnosis. RESEARCH
DESIGN AND METHODS—Fifty-four DPT-1 participants (22 in the parenteral trial and 32 in
the oral trial) were studied. All had oral glucose tolerance tests (OGTTs) at 6-month intervals …
OBJECTIVE—There is little information regarding the pattern of metabolic deterioration before the onset of type 1 diabetes. The goal of this study was to utilize data from the Diabetes Prevention Trial–Type 1 (DPT-1) to obtain a picture of the metabolic progression to type 1 diabetes over a period of approximately 2.5 years before its diagnosis.
RESEARCH DESIGN AND METHODS—Fifty-four DPT-1 participants (22 in the parenteral trial and 32 in the oral trial) were studied. All had oral glucose tolerance tests (OGTTs) at 6-month intervals from approximately 30 to 6 months before diagnosis. The vast majority also had OGTTs at diagnosis. Changes in OGTT glucose and C-peptide indexes from 30 to 6 months before diagnosis were examined by calculating slopes of the indexes for each individual over that time period. Changes from 6 months before diagnosis to diagnosis were examined by paired comparisons of the OGTT metabolic indexes between the time points.
RESULTS—Glucose levels increased gradually from 30 to 6 months before diagnosis in both the parenteral and oral groups (P < 0.001 for all indexes). Area under the curve (AUC) C-peptide (P < 0.05) and AUC C-peptide–to–AUC glucose ratio (P < 0.001) values decreased in the oral group; peak C-peptide–to–2-h glucose ratio values decreased in both groups (P < 0.001). In participants who also had OGTTs at diagnosis, AUC C-peptide (parenteral group, P < 0.05) and peak C-peptide (oral group, P < 0.05) values decreased from the last 6 months before diagnosis; stimulated C-peptide–to–glucose ratio values decreased in both groups (P < 0.001). Conversely, fasting C-peptide levels increased in both groups (oral group, P < 0.01). Fasting C-peptide–to–fasting glucose ratio values remained constant throughout the 30-month follow-up.
CONCLUSIONS—These data indicate that over a period of at least 2 years, glucose tolerance gradually deteriorates as stimulated C-peptide levels slowly decline in a substantial number of individuals who develop type 1 diabetes. However, fasting C-peptide levels are maintained, even at diagnosis.
Am Diabetes Assoc