[A prospective cohort study on the associations between vitamin D nutritional status and cardiometabolic abnormities in children]

Objective: To investigate the relationships between vitamin D nutritional status and the risks of cardiometabolic abnormities in children. Methods: Data were obtained from the School-based Cardiovascular and Bone Health Promotion Program. In 2017, a total of 15 391 children aged 6-16 years in Beijing were selected by using a stratified cluster sampling method in the baseline survey. A Follow-up investigation was conducted in 2019. Log-binomial regression was used to analyze the relationships between baseline vitamin D nutritional status and the risks of cardiometabolic abnormities (obesity, hypertension, hyperglycemia, and dyslipidemia). Results: A total of 10 482 participants were involved in the study. The average vitamin D level was (35.6 ± 12.0) nmol/L, and the deficiency rate was 35.1%. The 2-year cumulative incidence rates of obesity, hypertension, hyperglycemia, high TC, high LDL-C, low HDL-C, high TG, and high non-HDL-C were 4.3%, 10.8%, 8.5%, 3.1%, 2.5%, 3.4%, 2.5%, and 3.9% respectively. After the adjustment of potential confounding factors, children with vitamin D inadequacy or deficiency had higher risks of high TC [RR (95%CI): inadequacy, 2.06 (1.19-3.58); deficiency, 2.80 (1.61-4.89)], high LDL-C [RR (95%CI): inadequacy, 1.67 (1.02-2.73); deficiency, 1.99 (1.19-3.33)], and high non-HDL-C [RR (95%CI): inadequacy, 2.00 (1.26-3.17); deficiency, 2.45 (1.53-3.92)] compared with children with adequate vitamin D, and the risks of them increased with the decrease of vitamin D level (trend P<0.05). The gender-stratified analysis showed that vitamin D deficiency was remained associated with high TC [RR (95%CI): boy, 2.64 (1.19-5.87); girl, 3.13 (1.43-6.83)] and high non-HDL-C [RR (95%CI): boy, 2.58(1.40-4.77); girl, 2.31 (1.10-4.84)]. Conclusions: The risks of abnormal TC, LDL-C, and non-HDL-C were inversely associated with vitamin D level. Maintenance of adequate vitamin D status in children may contribute to the early prevention of cardiovascular diseases.