ABSTRACT
Background: To assess association of vitamin D deficiency with cardiac and pulmonary status in infants with acute bronchiolitis. Methods: Infants hospitalized with acute bronchiolitis were enrolled and classified as those with serum 25-hydroxyvitamin D (25-OHD) below or equal and above 20 ng/mL. The primary outcomes were cardiopulmonary involvement defined by elevation of NT-ProBNP, alteration of echocardiographic parameters and respiratory support requirements. The secondary outcomes were the need for PICU admission and duration of hospitalization. Results: 92 (50 males) infants with median (IQR) age of 1 (0.5-3) month were included with median (IQR) serum 25-OHD level 27.4 (11.4-40.3) ng/mL. 43 (47%) patients had serum 25-OHD level below 20 ng/mL with left ventricle dysfunction (P=0.008), right ventricle dysfunction (P=0.008) and pulmonary hypertension (P=0.007) on echocardiography more commonly than those with serum 25- OHD ?20 ng/mL. The median (IQR) serum NT-ProBNP levels were higher in those with low 25-OHD levels than normal 25-OHD levels [2232.2 (461.4-4313.3) and 830.4 (312.7- 2579.5)], respectively (P=0.003). Low 25-OHD levels were associated with increased risk for PICU admission (OR 3.9 (95% CI 1.5-10.1); P=0.004), higher rates of non-invasive ventilation (P=0.048) and mechanical ventilation (P=0.005) and longer duration of hospitalization (P=0.015). Conclusion: Low serum vitamin D level was associated with clinical severity and impaired cardiac and pulmonary status in infants with acute bronchiolitis