Nocturnal Cough and Sleep Quality to Assess Asthma Control and Predict Attacks.

Objective markers for asthma, that can be measured without extra patient effort, could mitigate current shortcomings in asthma monitoring. We investigated whether smartphone-recorded nocturnal cough and sleep quality can be utilized for the detection of periods with uncontrolled asthma or meaningful changes in asthma control and for the prediction of asthma attacks. We analyzed questionnaire and sensor data of 79 adults with asthma. Data were collected in situ for 29 days by means of a smartphone. Sleep quality and nocturnal cough frequencies were measured every night with the Pittsburgh Sleep Quality Index and by manually annotating coughs from smartphone audio recordings. Primary endpoint was asthma control assessed with a weekly version of the Asthma Control Test. Secondary endpoint was self-reported asthma attacks. Mixed-effects regression analyses showed that nocturnal cough and sleep quality were statistically significantly associated with asthma control on a between- and within-patient level (p < 0.05). Decision trees indicated that sleep quality was more useful for detecting weeks with uncontrolled asthma (balanced accuracy (BAC) 68% vs 61%; Δ sensitivity -12%; Δ specificity -2%), while nocturnal cough better detected weeks with asthma control deteriorations (BAC 71% vs 56%; Δ sensitivity 3%; Δ specificity -34%). Cut-offs using both markers predicted asthma attacks up to five days ahead with BACs between 70% and 75% (sensitivities 75 - 88% and specificities 57 - 72%). Nocturnal cough and sleep quality have useful properties as markers for asthma control and seem to have prognostic value for the early detection of asthma attacks. Due to the limited study duration per patient and the pragmatic nature of the study, future research is needed to comprehensively evaluate and externally validate the performance of both biomarkers and their utility for asthma self-management.

Informations de copyright

© 2020 Tinschert et al.

Déclaration de conflit d'intérêts

PT, FB, EF, and TK are affiliated with the Center for Digital Health Interventions (www. c4dhi. org), a joint initiative of the Department of Management, Technology and Economics at ETH Zurich and the Institute of Technology Management at the University of St. Gallen, which is funded in part by the Swiss health insurer CSS. CSS insurance supported the recruitment of participants but had no role in study design, app design, data management plans, or in reviewing and approving the manuscript for publication. PT further reports the foundation of a company, Resmonics AG, which is partly based on the results of this paper, during the conduct of the study. CS-S reports personal fees from AstraZeneca, GlaxoSmithKline, Novartis, and Boehringer Ingelheim, outside the submitted work. EF and TK further report, to be cofounders of Pathmate Technologies AG, a university spin-off company that creates and delivers digital clinical pathways and has used the open-source MobileCoach platform for that purpose, too (however, Pathmate Technologies is not involved in the study app described in this paper), outside the submitted work. The authors report no other potential conflicts of interest for this work.