Vitamin D and Asthma: Another Dimension

In this issue of the Journal, Gupta and colleagues (pp. 1342‐1349) add to the ever-enlarging body of literature reporting associations between vitamin D status (as reflected by serum 25(OH)D concentrations) and measures of asthma severity and control (1). In a well-characterized clinical cohort of children with either moderate or severe (treatment-resistant) asthma, they investigated associations between serum 25(OH)D and lung function, asthma control, exacerbations, and medication history. As might be expected in light of prior reports, the investigators found an inverse relationship between 25(OH)D and asthma severity, exacerbations, and inhaled glucocorticoid requirement, and a positive relationship between 25(OH)D and both lung function and asthma control. These findings validate, using data obtained directly from patients with severe asthma, other reports in which vitamin D status is associated with asthma severity in children (2‐4). The authors take their findings a step further, however, by also providing us with data regarding vita