Kimura H, et al. - Researchers characterized the clinical and biomarker features related to asthma exacerbations in severe asthma, including “past exacerbation status” as a confounding factor. They used multivariate analysis and compared three groups of patients: consistent non-exacerbators (CNE, subjects who did not experience any exacerbation over the 3-year period); consistent frequent exacerbators (CFE, subjects with frequent exacerbation, defined as those who had 2 or more exacerbations within 1 year, throughout the 3-year period); and intermittent exacerbators. Findings demonstrated that in predicting future asthma exacerbation, a significant potential of FeNO measurement was noted, which was independent of the “past exacerbation history.”