Low vitamin D status is associated with obesity but no other cardiovascular risk factors in Chinese children and adolescents

Abstract

Background and aims: Evidence on relationship between vitamin D status and cardiovascular health in childhood remains inconsistent. This study aimed to investigate vitamin D status and its relationship with cardiovascular risk factors in Chinese children and adolescents.

Methods and results: Cross-sectional data were obtained from 2680 children and adolescents aged 7-18 y in Guangzhou, South China. Anthropometric and socioeconomic characters, concentration of serum 25-hydroxyvitamin D [25(OH)D], fasting blood glucose and lipids, as well as information about diet and physical activity were measured and collected. Logistic regression model was adopted to analyze the associations between 25(OH)D levels and cardiovascular risk factors including obesity, high blood pressure, dyslipidemia, hyperglycemia, and metabolic syndrome. Overall, median level of 25(OH)D was 19.74 ng/mL. The prevalence rates of vitamin D deficiency and inadequacy were 7.5% and 44.4%, both of which were highest among adolescents aged 14-18 y (14.5% and 51.6%, respectively). As vitamin D level increased, an upward trend in fasting glucose concentrations was observed in subjects with normal fasting glucose level, but not in subjects with hyperglycemia. Among the assessed cardiovascular risk factors, vitamin D status was only inversely associated with general obesity, and the adjusted odds ratio was 1.95 (95% CI: 1.08-3.49), comparing the lowest 25(OH)D quartile with the highest one.

Conclusions: Vitamin D deficiency and inadequacy remain a concern among school-aged children and adolescents in Guangzhou, South China, particularly in adolescents aged 14-18 y. However, low vitamin D status was found only associated with general obesity but no other cardiovascular risk factors.

Keywords: Cardiovascular risk factors; Children and adolescents; Obesity; Vitamin D.