No Protective Effect of Calcitriol on β-Cell Function in Recent-Onset Type 1 Diabetes
The IMDIAB XIII trial
- Carla Bizzarri, MD1,
- Dario Pitocco, MD2,
- Nicola Napoli, MD3,
- Enrico Di Stasio, MD2,
- Daria Maggi, MD3,
- Silvia Manfrini, MD3,
- Concetta Suraci, MD4,
- Maria Gisella Cavallo, MD5,
- Marco Cappa, MD1,
- Giovanni Ghirlanda, MD2,
- Paolo Pozzilli, MD3 and
- the IMDIAB Group*
- 1Department of Endocrinology and Diabetes, Bambino Gesù Children's Hospital, Rome, Italy;
- 2Department of Diabetology, Catholic University, Rome, Italy;
- 3Department of Endocrinology and Diabetes, University Campus Bio-Medico, Rome, Italy;
- 4Department of Diabetology, Sandro Pertini Hospital, Rome, Italy;
- 5Department of Medical Therapy, University Sapienza, Rome, Italy.
- Corresponding author: Paolo Pozzilli, .
OBJECTIVE We investigated whether supplementation of the active form of vitamin D (calcitriol) in recent-onset type 1 diabetes can protect β-cell function evaluated by C-peptide and improve glycemic control assessed by A1C and insulin requirement.
RESEARCH DESIGN AND 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 μg/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 β-cell function in subjects (including children) with recent-onset type 1 diabetes and high C-peptide at diagnosis.
↵*A complete list of the members of the IMDIAB Group can be found in the appendix.
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- Received May 10, 2010.
- Accepted June 9, 2010.
- © 2010 by the American Diabetes Association.
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