Alveolar nitric oxide concentration plays an important role in identifying cough variant asthma and assessing asthma control in children

AbstractObjective To study the value of alveolar nitric oxide concentration (CaNO) in the identification and disease control of cough variant asthma.Methods A retrospective study was conducted on cough variant asthma (CVA-Group), nonasthmatic cough (NAC-Group) and healthy control children (C-Group) aged 5–12 years. The exhaled nitric oxide and spirometry test results of the three groups were collected and compared.Results A total of 410 children were included in this study, including 190 in the CVA-Group, 183 in the NAC-Group, and 37 in the C-Group. The CaNO values of the CVA-Group [11.40 ppb (8.48–14.25)] were significantly higher than those of the NAC-Group and C-Group (all p values <.05). The MMEF %pred values of the CVA-Group [63.65 (56.28–73.58)] were significantly lower than those of the NAC-Group and C-Group (all p values <.05). FeNO50, JawNO and other spirometry indices (FVC %pred, FEV1%pred, FEV1/FVC %pred) showed no significant difference among the three groups. ROC curve analysis showed that the optimal cutoff point value of CaNO was 9.45 ppb, corresponding to 0.816 sensitivity and 0.736 specificity. Spearman correlation analysis showed a significant negative correlation between the CaNO measurement and CVA control score.Conclusions CaNO can not only help identify CVA early in children aged 5–12 years with chronic cough but is also significantly negatively correlated with the CVA control score.Keywords: Alveolar nitric oxide concentration (CaNO)cough variant asthma (CVA)identifycontrol assessmentchildren AcknowledgementsWe acknowledge the assistance of the patients and their caregivers involved in the study, the staff of the Department of Pediatrics, The First Hospital Affiliated to Army Medical University.Declaration of interestThe authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.Data availability statementAll data generated or analyzed during this study are included in this published article.Additional informationFundingThis work was supported by Chongqing Science and Health Joint medical scientific research project: Noninvasive biomarkers combined with IOS lung function detection. Clinical study of asthma in preschool children [grant number: 2020MSXM039] and Special Project to Enhance The Scientific Innovation Ability of The Army Medical University [grant number: 2019XLC2004].