Vitamin D deficiency was infrequent among infants hospitalized with respiratory syncytial virus bronchiolitis, and when present, occurred among young infants and infants who breast-fed, according to study findings in The Journal of the Pediatric Infectious Diseases Society.
Avraham Beigelman, MD, MSCI, of the Washington University School of Medicine, and colleagues assessed 145 infants, with a mean age of 4.3 months, who were enrolled in the RSV Bronchiolitis in Early Life II (RBEL II) cohort from 2009 to 2012. All infants tested positive for RSV and had physician-documented wheezing. Researchers evaluated the relationship between vitamin D status at enrollment and the duration of hospitalization, lowest oxygen saturation measured during hospitalization, and bronchiolitis severity score.
The mean duration of hospitalization was 72.9 ± 49.8 hours. The mean lowest oxygen saturation was 90.6% ± 5.2% and the mean bronchiolitis severity score was 7.6 ± 2.1.
Regarding baseline vitamin D levels, median serum level was 36.8 ng/mL. Fourteen infants (9.7%) had vitamin D levels below 20 ng/mL, indicating vitamin D deficiency. Twenty-three infants (15.8%) had serum levels between 20 and 29.9 ng/mL.
Vitamin D-deficient infants were younger than infants with vitamin D levels of 20 ng/mL or greater. Vitamin D levels were lower among infants who were breast-fed. Infants who reported any formula feeding had higher levels of vitamin D. Vitamin D levels did not differ between infants who consumed solid foods and those who did not.
Mean duration of hospitalization did not differ between vitamin D-deficient infants and infants with normal levels. Vitamin D was not associated with any of the clinical indicators of bronchiolitis severity.
“Our results indicate that, among infants who required hospital-based care for acute RSV bronchiolitis, vitamin D status was not associated with the severity of bronchiolitis. These results need to be confirmed in additional larger cohorts with greater variability of bronchiolitis severity (including hospitalized and non-hospitalized infants). In addition, further studies are needed to determine whether vitamin D status, and its potential association with RSV bronchiolitis, is a risk factor for subsequent respiratory outcomes such as recurrent wheezing and asthma,” the researchers concluded.
Disclosure: See the study for a full list of disclosures.