[Pancreatic function assessment in type 1 diabetes mellitus patients according to disease duration].
Patients with type 1 diabetes (T1D) may exhibit some residual insulin secretion for many years after their diagnosis. This has been associated with a more favorable prognosis.


OBJECTIVE
To analyze insulin secretion in individuals with T1D using C-peptide (CP) response to glucagon and comparing patients with recent onset (<5 years - Group 1) and long-standing disease (>5 years -Group 2).


METHODS
Subjects with T1D had their blood sampled before (fasting) and 6 minutes after glucagon infusion for CP, HbA1c and anti-GAD measurement.


RESULTS
Forty-three individuals were evaluated, 22 in Group 1 and 21 in Group 2. Preserved insulin secretion (CP >1.5 ng/mL) was observed in 6 (13.9%) and in 8 (18.6%) patients before (CP 1) and after (CP 2) glucagon stimulus, respectively, showing no difference between the groups (p=0.18 and 0.24). CP 1 and CP 2 were detectable (>0.5 ng/dL) in 13 (30.2%) and 18 (41.9%) patients, respectively. Both were more frequent in Group 1 than in Group 2 (p=0.45 for CP1/p=0.001 for CP 2). Similar serum levels where seen between the groups, both before and after stimulus (1.4+/-0.8 vs. 1.2+/-1.0; p=0.69 and 1.8+/-1.5 vs. 1.7+/-0.8; p=0.91). Group 1 presented an inverse correlation between disease duration and CP 2 (R=-0.58; p=0.025).


CONCLUSIONS
A significant number of patients with T1D have detectable residual insulin secretion, especially in the first 5 years of disease. These subjects are an ideal population for clinical trials that target the prevention of beta cell function loss in T1D.
Dantas
Joana R
JR
Instituto Estadual de Diabetes e Endocrinologia Luiz Capriglione, Rio de Janeiro, RJ, Brazil. joanardantasp@ig.com.br
Almeida
Mirella H
MH
Barone
Bianca
B
Campos
Felipe
F
Kupfer
Rosane
R
Milech
Adolpho
A
Zajdenverg
Lenita
L
Rodacki
Melanie
M
Oliveira
José Egídio P de
JE
D000293:Adolescent; D002096:C-Peptide / Q000032:analysis / Q000378:metabolism; D016009:Chi-Square Distribution; D003922:Diabetes Mellitus, Type 1 / Q000208:ethnology / Q000276:immunology / Q000378:metabolism*; D005260:Female; D005934:Glucagon; D005968:Glutamate Decarboxylase / Q000032:analysis / Q000276:immunology; D006442:Glycated Hemoglobin / Q000032:analysis / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D008297:Male; D010179:Pancreas / Q000378:metabolism* / Q000503:physiopathology; D013997:Time Factors; D055815:Young Adult
D002096:C-Peptide; D005934:Glucagon; D005968:Glutamate Decarboxylase; D006442:Glycated Hemoglobin; D007328:Insulin