Digital biomarkers: Redefining respiratory care

Respiratory diseases, common examples of which include asthma and chronic obstructive pulmonary disease (COPD), affect one in five people in the UK.¹ The economic burden of these conditions is high, with more than 1.1 million hospital admissions and costs to the NHS of more than £9.9 billion each year. These burdens are set to increase, with a 40% rise in the incidence of COPD alone expected by 2030.² The adoption of new approaches within the respiratory care space is undoubtedly needed to relieve the pressure on health services that are already struggling.

Those key challenges impacting the care of respiratory diseases include delays in diagnosis due to the intermittent nature of disease symptoms, and the need for specialist centres and equipment (e.g., spirometry). It has been estimated that one in four people with COPD may wait more than five years, and one in twelve more than ten years, for a diagnosis.³ The early diagnosis of respiratory diseases is essential for preventing unnecessary delays in treatment, further loss of lung function, and improving the sufferer's quality of life.

Another challenge for many respiratory conditions is the occurrence of respiratory exacerbations. These acute episodes of worsening disease symptoms often result in hospitalisation, healthcare utilisation, further decline in lung function, and mortality.⁴ Hence, the early detection of these symptoms and prompt intervention are key to improving long-term patient outcomes. Other challenges affecting treatment effectiveness, in particular, include poor medication adherence and improper inhaler technique, impacting up to 92% of asthma and COPD patients.⁵

Transforming respiratory care with digital biomarkers

As healthcare progresses into the digital age, digital biomarkers offer tremendous potential for transforming and improving outcomes in respiratory care, particularly for conditions such as COPD and asthma.⁶ The term digital biomarker refers to objective and quantifiable physiological and behavioural measurements that have been collected using digital devices such as wearables, mobile apps, and/or sensors.⁷

The use of digital biomarkers can help improve patient care by enabling the remote and continuous monitoring of patients outside the clinical setting, providing a more complete and real-world picture of an individual’s health. In this way, digital biomarkers can aid in the detection of oncoming respiratory exacerbations, enabling clinicians to be more proactive and personalise treatment approaches.^8,9

Additionally, digital biomarkers can provide clinicians with objective information on medication adherence, treatment responses, and adverse events enabling more personalised treatment. These same insights can help pharmaceutical companies better understand the real-world performance of therapies to help guide product development and commercialisation.¹⁰

Promising respiratory biomarkers

Several different digital biomarkers are already showing promise in respiratory care, including:

Portable spirometers paired with smartphone apps can enable patients to perform lung function testing at home. In COPD patients, home monitoring has been shown to have a positive effect in reducing respiratory exacerbations, hospitalisations, and improving quality of life.¹¹

Smartphone apps can perform non-invasive monitoring of vital signs, including heart rate, respiratory rate, and blood oxygen levels to help detect worsening respiratory symptoms or an oncoming respiratory exacerbation.¹²

Pedometer or accelerometer tracking of physical activity through wearables can serve as an indicator of a patient's respiratory status. Lower levels of physical activity have been associated with a higher risk of exacerbations, and exacerbation-related hospitalisations in patients with COPD.^13,14

Digital inhaler sensors can provide information about medication usage. Digital inhalers have been linked with improvements in medication adherence, exacerbation risk, and patient outcomes.¹⁵

Sleep monitoring using consumer wearables can enable the evaluation of sleep quality and the detection of sleep disorders, like obstructive sleep apnoea, which is highly prevalent in COPD and asthma sufferers.^16,17 Individuals suffering from obstructive sleep apnoea and COPD are at a higher risk of death and exacerbations when left untreated.¹⁸

Symptom journalling apps enable patients to log daily symptoms, such as cough, wheezing, and chest tightness. Longitudinal logs can provide personalised insights to help identify exacerbation triggers through the tracking of symptom trends.

Challenges for digital biomarkers

Digital biomarkers offer enormous potential in respiratory care; however, effectively utilising them remains complex and numerous hurdles must be overcome for their potential to be fully realised.¹⁹ These challenges include appropriate biomarker selection, validation, and their successful integration into clinical workflows. Other challenges relating to the digital tools used for data collection include adoption issues, regulatory requirements, and privacy risks.

Undoubtedly the adoption of digital biomarkers in respiratory care promises to deliver significant value to patients and healthcare systems. In future, we can expect to see the further evolution of digital biomarkers with improved data sharing from different patient groups and the utilisation of multidimensional data from more diverse sources. Additionally, we are likely to see an increase in the number of decentralised clinical trials involving remote monitoring technologies, and the implementation of AI and machine learning techniques to generate novel health insights.

References

1. https://www.england.nhs.uk/ourwork/clinical-policy/respiratory-disease/#:~:text=The%20annual%20economic%20burden%20of,the%20UK%20%C2%A311billion%20annually
2. https://transform.england.nhs.uk/key-tools-and-info/digital-playbooks/respiratory-digital-playbook/digital-service-to-manage-high-risk-chronic-obstructive-pulmonary-disease-copd-patients/#:~:text=Situation,hospital%20management%20of%20COPD%20exacerbations
3. https://www.asthmaandlung.org.uk/transforming-respiratory-diagnostics-way-forward
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