Voice as a Biomarker: TACTICAS Study Published in ERJ Open Research and Featured by the European Respiratory Society

Study demonstrates that changes in a person’s voice, captured on their own smartphone, signal the onset of asthma and COPD flare-ups

Results from the TACTICAS study (Telemonitoring for Asthma and COPD Through voICe AnalysiS) have been published in ERJ Open Research, the peer-reviewed open-access journal of the European Respiratory Society (ERS). The study was conducted by Maastricht University Medical Center+ (MUMC+) with the support of Zana Technologies. The published findings show that voice changes recorded through a mobile app can indicate the very beginning of an exacerbation in people living with asthma or Chronic Obstructive Pulmonary Disease (COPD).

The publication was selected by the ERS for international dissemination and is featured in the ERS press release.

Peer-reviewed evidence that voice reflects respiratory deterioration

Exacerbations, which are sudden worsenings of breathlessness, coughing and phlegm, interfere with daily life and the lack of prompt treatment can be dangerous. Detecting them typically requires a hospital or clinic visit, introducing delay at exactly the moment that speed matters.

The TACTICAS study included 38 people with COPD and 35 people with asthma, treated at Maastricht University Medical Center+ and at Laurentius Hospital, Roermond, the Netherlands. Over 12 weeks, participants used a purpose-built app, co-designed with patients and Zana, to record their voice daily from home: a sustained ‘a’ sound followed by reading a short text or answering a question, alongside a daily symptom questionnaire.

Comparing voice recordings against symptom data, the analysis found that at the very onset of a flare-up, participants’ voices deteriorated in pitch, in the number of pauses, and in voice quality and that these measures recovered as the exacerbation subsided.

Study lead Dr. Sami Simons, assistant professor at Maastricht University and consultant respiratory physician at MUMC+, explained the mechanism: “As the airways constrict during an exacerbation, the air that passes the vocal folds is limited. This weakens the normal vibration of the vocal folds, making it harder to keep the voice steady.” The result is a voice that sounds breathier and rougher.

Critically, all of this was captured in the home environment, on participants’ own mobile phones.

From detection to prediction: three days before symptoms

Building on the TACTICAS dataset, Zana has additionally developed machine learning algorithms that detect exacerbations from voice changes as early as three days before symptoms appear. These algorithms have been described in a separate peer-reviewed publication.

This progression from establishing voice as a biomarker, to building predictive models on top of it is the core of Zana’s approach to respiratory care: turning a low-friction routine of daily voice interaction into an early-warning signal that reaches the patient before the flare-up does.

Recognition from the European Respiratory Society

Commenting on the study in the ERS press release, Dr. Marc Miravitlles, Vice President of the European Respiratory Society and Senior Researcher and Consultant at Vall d’Hebron University Hospital, Barcelona, who was not involved in the research, said: “If follow-up studies are positive, this technology could allow better monitoring and care for patients with asthma or COPD via a mobile phone wherever they are in the world. This is a good example of how new technologies and AI could really improve the quality of life of our patients with chronic respiratory diseases.”

An open platform for vocal biomarker research

The app developed for TACTICAS supports voice journaling and longitudinal data collection in the home environment, on participants’ own smartphones. Zana makes this app available to researchers and teams pursuing work on vocal biomarkers across respiratory disease and beyond. Interested groups are welcome to contact us to discuss deployment in their own studies.

Acknowledgements

Zana thanks Dr. Simons and team for their leadership of the trial, Loes van Bemmel for leading the research, the clinical team at Laurentius Hospital Roermond, and the patients who contributed their voices over twelve weeks. This work was carried out in collaboration with Maastricht University, the Institute of Nutrition and Translational Research in Metabolism (NUTRIM), and the Lung Foundation Netherlands (Longfonds).

Publication

Voice as biomarker for early exacerbation detection in asthma and COPD: the TACTICAS study. ERJ Open Research. DOI: 10.1183/23120541.01737-2025

ERS press release: Voice changes measured with a mobile phone can signal a flare up in asthma or COPD