Vitamin D and Forced Oscillation Technique parameters in asthmatic children
Sunday, March 4, 2018
South Hall A2 (Convention Center)
Napatsayod Swangtrakul, MD, Wiparat Manuyakorn, MD
RATIONALE: Vitamin D was known to be involved in regulation of immunity and maintenance of pulmonary health. This study aims to evaluate relationship between serum total 25-hydroxyvitaminD (25(OH)D), and pulmonary parameter assessed by FOT. Secondary outcome was to study correlation of vitamin D and, dosage of inhaled corticosteroids (ICS) being use, aero-allergen sensitization, and blood eosinophil.

METHODS: Asthmatic children, age 3-18 years were enrolled. Demographic data, serum total 25-hydroxyvitaminD (25(OH)D), complete blood count, skin prick test (SPT), and FOT parameters, including resistance (Rrs), reactance (Xrs), frequency of resonance (Fres) and area of reactance (ALX), were recorded.

RESULTS: 70 asthmatic children were recruited. The mean ± SD of age was 10.3 ± 3.2 years old. 39 of them was male (55.7%). Serum total 25(OH)D was 23.2 ± 6.5 ng/ml. There was no significant differences in the serum total 25(OH)D between male and female children (24.1±6.7 vs 21.9±5.9 ng/ml, P=0.17). Hypovitaminosis D (<30 ng/ml) was observed in 59 (84.2%) children: 33 children were vitamin D insufficiency and 26 children were vitamin d deficiency. Serum total 25(OH)D showed significant correlation with respiratory resistance at 5Hz (R5)(R=0.36, P=0.02), respiratory resistance at 20Hz (R20)(R=0.37, P=0.02), post bronchodilator (BD) R5(R=0.40, P=0.01), post-BD R20(R=0.41, P<0.001), post-BD resistance difference at R5-R20 (R=0.34, P=0.04), post-BD Fres(R=0.34,P=0.04), post-BD ALX(R=0.34, P=0.04). Blood eosinophil, aeroallergen sensitization, dosage of ICS and previous year loss of control in asthma did not associate with total 25(OH)D level.

CONCLUSIONS: Vitamin D may have a role on pulmonary parameters assessed by FOT in asthmatic children.