Vitamin D is a key indicator influencing the parathyroid hormone level in children 6-18 years with cow's milk protein allergy.

OBJECTIVE

Few studies have examined the relationship between vitamin D and parathyroid hormone (PTH) in school-aged children with cow's milk protein allergy (CMPA). This study aimed to investigate the role of vitamin D on PTH in this population.

METHODS

Data for this cross-sectional analysis were obtained from the 2005-2006 National Health and Nutrition Examination Survey database. XGBoost and Random Forest models were employed to explore the importance of vitamin D on PTH. Multi-factorial linear regression analysis, Pearson correlation analysis, and quantile regression were conducted. Sensitivity analyses, including trend regression, stratified analyses, generalized additive model (GAM), and polynomial regression analyses, were used to verify the stability of their association.

RESULTS

The median level of PTH in 238 children was 35.000[27.000,45.000] pg/mL, and 38.235% of participants had vitamin D insufficiency and deficiency. XGBoost and Random Forest models identified vitamin D as the most significant factor influencing PTH levels. Multi-factorial linear regression analysis revealed that lymphocytes and vitamin D were independent influencing factors on PTH. Pearson correlation and quantile regression analyses suggested that the absolute value of the correlation coefficient between vitamin D and PTH was higher than that between lymphocytes and PTH (-0.323 vs. 0.151). Sensitivity analyses confirmed the correlation stability of vitamin D and PTH.

CONCLUSION

In the CMPA school-aged children, 38.235% exhibited vitamin D insufficiency and deficiency. Vitamin D level was significantly and independently related to PTH levels.