This participant-blinded parallel-group randomized placebo-controlled study demonstrated that alfacalcidol (vitamin D analogue) preserves beta cell function in newly diagnosed type 1 diabetes (T1DM) in children. Subjects from outpatient clinic were randomized to intervention and control groups. Inclusion: (1) age 8-15, (2) T1DM, (3) duration <8 weeks, (4) no chronic diseases, (5) stable diet. Exclusion: (1) vitamin D, calcium supplements or fortified foods, (2) hypercalcemia. Intervention group received alfacalcidol 0.25 μg twice daily, while control group received placebo. Insulin given physician-titrated to blood glucose. Safety monitored by serum calcium and phosphate. Beta cell function assessed at 0, 3, 6 months using fasting C-peptide (FCP) and daily insulin dosage per body weight (DID). Primary outcome measured using multivariate repeated measures GLM-ANOVA, with FCP and DID as primary measures and age, gender, sunlight exposure, 25-hydroxy vitamin D, and HbA1c as covariates. Of 61 subjects, 7 dropped out. GLM-ANOVA showed that groups were different (p=0.019, Eta-squared=0.087), with no significant covariates. FCP was higher and DID lower in the intervention group, with males having stronger responses to alfacalcidol (p=0.001). No adverse effects were observed. The study confirmed that alfacalcidol can safely preserve beta cell function in newly diagnosed T1DM in children, with a stronger effect in males. IRCT201205159753N1.

Background: In this study, the prevalence of vitamin D deficiency was assessed in a group of children and adolescent patients with recent-onset type 1 diabetes mellitus (T1DM). Methods: Fifty-three patients with age 8–18 years and duration of T1DM less than 8 weeks were recruited. A food frequency questionnaire (FFQ) was used to assess dietary vitamin D and calcium intake. Sunshine exposure was measured using a questionnaire to quantify the amount of time children spent in the sun and other sun-related habits, and a sun index score was generated. Serum 25(OH)D < 20 ng/ml was considered as vitamin D deficiency. Logistic regression was used to assess predictors of vitamin D deficiency. Results: All patients were vitamin D deficient (77%) or insufficient (23%). In a logistic regression model, it was shown that the risk of being vitamin D deficient was significantly decreased by sunlight exposure ≥ 15 minutes during the weekends versus < 15 minutes (OR: 0.06, 95% CI: 0.01–0.75; P=0.029). In addition, vitamin D deficiency in boys was lower than girls in this model (OR: 0.164 [95% CI: 0.02–1.11]; P = 0.063). Conclusion: Vitamin D deficiency is highly prevalent among children and adolescents with T1DM in Iran. Boys and children with ≥ 15 minutes sunlight exposure in weekends were less likely to be vitamin D deficient than girls and those with < 15 minutes sunlight exposure.

Specific alleles at the HLA-DRB1, -DQA1, and -DQB1 loci seem to be associated with variable risks of developing type 1 diabetes (T1D). This study assessed the distribution of HLA-DR and -DQ alleles among Iranian T1D patients and healthy controls. In this study, HLA-DRB1, -DQA1, and -DQB1 alleles were determined in 100 children with T1D and 100 unrelated healthy controls. The following alleles were found to have a strong positive association with T1D: DRB1*0301, DRB1*0401, DRB1*0402, DQA1*0301, DQA1*0501, DQB1*0201, and DQB1*0302. Meanwhile, protective associations were found for DRB1*1001, DRB1*1101, DRB1*15, DRB1*16, DQA1*0102, DQA1*0103, DQB1*0301, DQB1*0501, and DQB1*0602 alleles. The haplotypes found most frequently among patients with T1D were DRB1*0301-DQA1*0501-DQB1*0201, DRB1*0401-DQA1*0301- DQB1*0302, and DRB1*0402-DQA1*0301-DQB1*0302, whereas DRB1*1101-DQA1*0501-DQB1*0301 and DRB1*16-DQA1*0102- DQB1*0501 haplotypes were negatively associated with the disease. These results confirm the previously reported association of specific HLA-DR and HLA-DQ alleles and haplotypes with T1D in Iranian population. The notable difference was the identification of DRB1*16-DQA1*0102-DQB1*0501 as a protective haplotype and the absence of a negative association of DRB1*1301-DQA1*0103-DRB1*0603 with T1D.