Vitamin D status is related to severity at onset of diabetes and worse glycemic control

Does vitamin D supplementation benefit patients with type 1 diabetes mellitus who are vitamin D deficient? A study was performed at the Sudan Childhood Diabetes Center from 2019 to 2022

Objectives

Type 1 diabetes mellitus is a chronic autoimmune disease caused by insufficient production of insulin. Many studies have linked type 1 diabetes mellitus to vitamin D3 deficiency. We investigated the prevalence of vitamin D deficiency in Sudanese children and adolescents with type 1 diabetes mellitus and assessed the impact of vitamin D deficiency treatment on their glycemic control.

Methods

In 2019-2022, we conducted a quasi-experimental study on 115 children with type 1 diabetes mellitus (1-19 years old) at the Sudan Childhood Diabetes Center. Vitamin D supplements were given orally to deficient patients for 3 months. The concentrations of hemoglobin A1c, fasting blood glucose, insulin dosage, and vitamin D (25-hydroxyvitamin D (25(OH)D)) were measured before and after vitamin D3 administration. One-way ANOVA and paired sample t-tests were used to evaluate the effect of supplementation.

Results

Only 27% of type 1 diabetes mellitus children were deficient in vitamin D, whereas 31.1% were inadequate and 40.9% were sufficient. The administration of vitamin D supplements slightly improved hemoglobin A1c levels in 67.7% of the patients, but the difference was not significant (mean 10.8 ± 2.1% before, 10.1 ± 2.5% after, p0.05 = 0.199). However, there was a significant decrease in the fasting blood glucose level (mean: 174.978.5-136.759.1 ng/ml; p0.05 = 0.049). Vitamin D levels were significantly increased after treatment (mean = 49.6 ng/mL; t-test = -11.6, 95% CI 40.8-(-28.6); p0.05 = 0.000). After vitamin D3 supplementation, 25.8% of individuals changed their insulin dosage; however, there was no significant variation in insulin needs.

Conclusions

The prevalence of vitamin D deficiency in children and adolescents with type 1 diabetes mellitus in Sudan is relatively high; incorporating vitamin D supplements in their treatment plan may improve their glycemic control.

Proportion of vitamin D deficiency in children/adolescents with type 1 diabetes: a systematic review and meta-analysis

BACKGROUND

The impact of vitamin D on type 1 diabetes has been a controversial topic in public health. Furthermore, significant differences in the proportion of vitamin D have been noted. The purpose of this systematic review was to determine the overall proportion of vitamin D deficiency in children/adolescents with type 1 diabetes (T1D).

METHODS

Based on six electronic databases (PubMed, Web of Science, Embase, Ovid Medline, ProQuest, and Cochrane Library), eligible studies since the databases' inception up to April 2022 were searched. Reference lists were also manually searched to identify additional studies. Overall, studies with statistical information on vitamin D deficiency in children and adolescents with T1D were included, and a random effects model was applied for the meta-analysis. In addition, subgroup and sensitivity analyses were carried out to evaluate heterogeneity, and publication bias was evaluated by using Egger's test.

RESULTS

A total of 45 studies involving 6,995 participants met the inclusion criteria; these included 25 countries covering Africa, Oceania, Europe, North America and Asia. The proportion of vitamin D deficiency in children/adolescents with T1D was 45% (95% confidence interval [CI] 37-54%, I2 = 97.94%). Subgroup analysis further revealed that the publication year, study design, vitamin D classification, season and geographical region significantly contributed to the variation in the reported incidence of vitamin D deficiency.

CONCLUSIONS

The results of the meta-analysis showed that the proportion of vitamin D deficiency among T1D children/adolescents was 45%. In addition, the proportion remains higher, which has important implications for adapting health and social care systems.