Vitamin D Insufficiency Associated With Insulin Resistance Independent of Obesity in Children

Children who are obese and have insulin resistance (IR) may be more likely to have vitamin D deficiency/insufficiency compared with children who are not obese and do not have insulin resistance, according to a study published in Diabetes.

Researchers conducted a cross-sectional epidemiological study of a representative sample of Greek school-aged children aged from 9 to 13 years (n= 2277) to examine the association between vitamin D levels and both obesity and IR.

Study results showed that boys compared with girls had higher body mass index (P =.004) and serum 23(OH)D concentrations (P <.001), and a lower Homeostasis Model Assessment of Insulin Resistance score.

Overall prevalence rates of overweight and obesity were 31.0% and 11.4%, respectively; however, boys were found to have a higher prevalence of obesity (13.8%) compared with girls (9.2%; P <.05). IR had an overall prevalence in the cohort of 29%, with a higher prevalence in girls (34.9%) compared with boys (23%; P < .001).

Vitamin D insufficiency was higher only in obese girls compared with in children who were either overweight or normal weight (P =.024). Regarding vitamin D status in the total sample, the prevalence rates of insufficiency and deficiency were 52.2% and 5.2%, respectively. When compared with boys, girls were found to have higher prevalence rates of vitamin D insufficiency and deficiency (56.7% vs 47.6% [P <.001] and 7.1% vs 3.3% [P <.001], respectively)].

In addition, there was a significant difference in vitamin D deficiency prevalence between children with IR and those without IR (7.1% vs 4.4%; P =.010). Both obese and nonobese children with IR, compared with children who were not obese with a normal insulin response, had a higher prevalence of vitamin D insufficiency (66% and 59.2% vs 49.8%; P <.05). The logistic regression analysis suggested that children with IR were 1.48 times more likely to be vitamin D insufficient compared with children with normal insulin status (95% CI, 1.2-1.84), but it did not show a significant association between obesity and vitamin D deficiency or insufficiency.

Researchers concluded that there was a high prevalence of vitamin D insufficiency observed in schoolchildren, specifically among children with IR and who were obese. The data suggest there may be a strong association between vitamin D insufficiency and IR that is independent of obesity. Clinicians should closely monitor the vitamin D levels in children who are obese and those with IR, as these children are at a significantly higher risk of having vitamin D deficiency and insufficiency and may require more aggressive vitamin D management.

Reference

Moschonis G, Androutsos O, Hulshof T, Dracopoulou M, Chrousos GP, Manios Y. Vitamin D insufficiency is associated with insulin resistance independently of obesity in primary schoolchildren. The Healthy Growth Study [published online April 2, 2018]. Pediatr Diabetes. doi: 10.1111/pedi.12678