No protective effect of calcitriol on beta-cell function in recent-onset type 1 diabetes: the IMDIAB XIII trial.
OBJECTIVE
We investigated whether supplementation of the active form of vitamin D (calcitriol) in recent-onset type 1 diabetes can protect beta-cell function evaluated by C-peptide and improve glycemic control assessed by A1C and insulin requirement.


METHODS
Thirty-four subjects (aged 11-35 years, median 18 years) with recent-onset type 1 diabetes and high basal C-peptide >0.25 nmol/l were randomized in a double-blind trial to 0.25 microg/day calcitriol or placebo and followed-up for 2 years.


RESULTS
At 6, 12, and 24 months follow-up, A1C and insulin requirement in the calcitriol group did not differ from the placebo group. C-peptide dropped significantly (P < 0.001) but similarly in both groups, with no significant differences at each time point.


CONCLUSIONS
At the doses used, calcitriol is ineffective in protecting beta-cell function in subjects (including children) with recent-onset type 1 diabetes and high C-peptide at diagnosis.
Bizzarri
Carla
C
Department of Endocrinology and Diabetes, Bambino Gesù Children's Hospital, Rome, Italy.
Pitocco
Dario
D
Napoli
Nicola
N
Di Stasio
Enrico
E
Maggi
Daria
D
Manfrini
Silvia
S
Suraci
Concetta
C
Cavallo
Maria Gisella
MG
Cappa
Marco
M
Ghirlanda
Giovanni
G
Pozzilli
Paolo
P
D000293:Adolescent; D000328:Adult; D002096:C-Peptide / Q000378:metabolism; D002117:Calcitriol / Q000494:pharmacology / Q000627:therapeutic use*; D002648:Child; D003922:Diabetes Mellitus, Type 1 / Q000188:drug therapy* / Q000378:metabolism*; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007004:Hypoglycemic Agents / Q000494:pharmacology / Q000627:therapeutic use; D007328:Insulin / Q000627:therapeutic use; D050417:Insulin-Secreting Cells / Q000187:drug effects* / Q000378:metabolism*; D008297:Male; D055815:Young Adult
D002096:C-Peptide; D002117:Calcitriol; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D007328:Insulin
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