Association between vitamin D levels and cardiovascular risk factors in obese children and adolescents.

BACKGROUND AND AIM

Childhood obesity is associated with an increased risk of chronic disease. We aimed to determine the association between vitamin D deficiency and cardiovascular risks in obese children.

METHOD

The studied children were selected from obese children who were followed up at obesity clinic, aged 6-17 years. Basic demographic information and laboratory data were collected retrospectively from hospital records.

RESULTS

A total of 310 students (178 [57.4%] girls) were evaluated for 25-hydroxyvitamin D (25[OH] D) levels in late winter/spring. The prevalence rates of vitamin D deficiency, insufficiency, and sufficiency were 62.3%, 34.5%, and 3.2%, respectively. Insulin resistance was observed in 146 (47.1%) children; the frequencies of dyslipidemia and hypertension were 31% and 19.4%, respectively. The mean atherogenic dyslipidemia ratio was higher in the deficient group (p = 0.049). Inverse correlations of 25(OH) D levels were observed with homeostasis model assessment of insulin resistance values (r = -0.146, p = 0.010). The mean values of 25(OH) D (ng/mL) were lower in girls (12.15 ± 6.60) than in boys (16.48 ± 8.69) (p < 0.05) and in children with hypertension (11.92 ± 5.48) than in those without (14.50 ± 8.24) (p < 0.05).

CONCLUSIONS

Vitamin D deficiency is observed more frequently than expected in obese children and adolescents. Our findings indicate that low 25(OH) D levels are associated with insulin resistance. Vitamin D deficiency could contribute to the morbidities associated with childhood obesity, such as insulin resistance or diabetes mellitus, increased cardiovascular/cardiometabolic risks, atherogenic dyslipidemia, and hypertension.