Table 1 Overview of the main studies that investigate the relation between vitamin D metabolites and IGF-1 in children
From: Vitamin D and growth hormone in children: a review of the current scientific knowledge
Reference | Study area, study design | Number of patients | Vitamin D metabolite considered | Correlation between vitamin D and IGF-1 | Other remarks | Limits |
|---|---|---|---|---|---|---|
Mortensen [66] | Denmark, RCT | 117 subjects (mean age 6.6 ± 1.5 years) randomly divided into 3 groups: 40 subjects who received a placebo for 20 weeks; 38 subjects who received a 10 mcg/day vitamin D supplementation for 20 weeks; and 39 subjects who received a 20 mcg/day vitamin D supplementation for 20 weeks | 25(OH)D | No correlation between 25(OH)D and IGF-1 or IGFBP-3 levels at baseline Positive correlation between 25(OH)D, IGF-1 and IGFBP-3 in group that received 20 mcg/day vitamin D supplementation for 20 weeks | Positive relationship between 25(OH)D and IGFPB-3 at baseline only in girls Positive relationship between 25(OH)D and IGFPB-3 in group that received 10 mcg/day vitamin D supplementation for 20 weeks Increased height in group that received 20 mcg/day vitamin D supplementation for 20 weeks compared to placebo group |  |
Marwaha [67] | India, prospective cohort | 847 healthy Indian girls (6–18 years old) | 25(OH)D | No correlation between 25(OH)D and IGF-1 or IGFBP-3 levels at baseline Increased IGF-1 and IGFBP-3 levels after 6 months vitamin D supplementation | No effect on PTH | Only girls studied 94.6% had 25(OH)D < 20 ng/mL |
Gannagé-Yared [68] | Lebanon, cross-sectional | 952 Lebanon subjects (mean age of 13.46 ± 2.80 years old) | 25(OH)D | No correlation between 25(OH)D and IGF-1 | – |  |
Nazif [71] | Egypt, cross-sectional | 58 subjects affected by CP (4–12 years old) and 19 healthy gender and age-matched controls | 25(OH)D | Positive correlation between 25(OH)D and IGF-1 | 25(OH)D and IGF-1 values significantly reduced compared to the healthy population | Numerous studies evidenced decreased IGF-1 levels in CP children |
Bereket [70] | Turkey, prospective cohort | 22 subjects affected by nutritional rickets (mean age of 1.3 ± 1.6 years old) | 25(OH)D | No correlation between 25(OH)D and IGF-1 or IGFBP-3 levels at baseline Positive correlation between 25(OH)D, IGF-1 and IGFBP-3 3 months after vitamin D megadose treatment | No effect on PTH No relationship between 25(OH)D and IGFBP-4 at baseline and after treatment |  |
Soliman [69] | Qatar, prospective cohort | 46 subjects affected by nutritional rickets (mean age of 13.1 ± 1.1 months) and 40 healthy controls (mean age of 14.3 ± 2.2 months) | 25(OH)D | Positive correlation between 25(OH)D and IGF-1 before and after vitamin D megadose treatment | Positive effect on the growth velocity SDS |  |