Assessing Remote Patient Monitoring for Detecting COPD Exacerbations

When managing COPD, early detection of exacerbations and earlier intervention are key factors to improving patient outcomes and preserving quality of life, explains Christopher B. Cooper, MD. Advances in telemedicine and remote patient monitoring (RPM) have demonstrated the potential to improve the care of patients with COPD who are at risk for exacerbations. “Digital health is a fast-moving field, especially in the current era of COVID-19,” says Dr. Cooper. “The ability to monitor patients with chronic diseases like COPD in their own homes has many advantages in terms of safety, cost, and frequency of assessment. However, the complexity of COPD and the variability of changes in exacerbations makes it challenging to determine the symptoms or physiological measures that have the best predictive value.”

Several recent systematic reviews concluded that RPM may be beneficial, but these investigations did not draw firm conclusions and noted that more research is needed. Of note, Dr. Cooper says previous studies have found that overly sensitive monitoring can lead to false positive results. “As such, further refinement of RPM is necessary to reduce these instances,” he says.

Early COPD Exacerbation Detection

Previously, Dr. Cooper and colleagues published data on a networked RPM system designed to detect COPD exacerbations early. Using statistical process control (SPC)—a concept borrowed from the engineering industry—the study demonstrated the feasibility of RPM in terms of capturing reliable data (see device images). “SPC simplifies the collection and interpretation of a longitudinal data series, averaging data over the preceding 7 days in order to identify clinically meaningful signals,” says Dr. Cooper. “The time to record symptoms, physical activity, inhaler use, pulmonary function, and SpO₂ was reduced from 12 to 6 minutes per day with SPC,” Dr. Cooper says. “This was less burdensome for patients, and some remained on RPM for up to 1 year.”

Extending their previous work with a paper published in the International Journal of Chronic Obstructive Pulmonary Disease, Dr. Cooper and colleagues explored the predictive value of parameters obtained from RPM in identifying COPD exacerbations. For this study, 17 patients with moderate to severe COPD received RPM during 7.17 patient-years of monitoring. Data were obtained on daily symptom scores, treatment adherence, self-reported activity levels, daily forced and slow spirometry, inspiratory capacity (IC), and oxygen saturation (SpO₂). The authors used these data to identify predictors of exacerbations.

A concordance analysis showed substantial agreement between a fall in forced vital capacity (FVC) and self-reported healthcare utilization events. There was also substantial agreement between increased use of inhaled short-acting bronchodilators and exacerbations. A moderate agreement was observed between a fall in forced expiratory volume in one second (FEV₁) and self-reported healthcare utilization events, and between SpO₂ less than 90% and exacerbations (Table).

“Our findings suggest that using RPM with a broader range of real-time symptoms and physiological parameters can give us a more detailed picture of COPD and the day-to-day fluctuations of disease activity,” says Dr. Cooper. “RPM identified a range of symptoms and physiological parameters that positively correlated with COPD exacerbations, most notably FVC, FEV₁, increased use of short-acting bronchodilators, and decreases in SpO₂. Importantly, more than 70% of patients adhered to the RPM protocols, but we expect this rate to increase substantially as RPM becomes more sophisticated.”

Important Implications

With further refinement, RPM might become a valuable tool for managing COPD in patients with a history of frequent exacerbations and in those with comorbidities that can worsen exacerbation outcomes. However, RPM requires further investigation to establish links between daily predictors and longer-term outcomes, such as disease progression, debility, and death. “We hope further enhancements in RPM will reduce false positive results and perhaps help decrease healthcare expenditures for COPD,” says Dr. Cooper.

Dr. Cooper says RPM will continue to be embraced and further investigated beyond the COVID-19 pandemic in COPD and in other chronic diseases. “A clinical trial is planned to explore RPM using 3-times weekly home spirometry in patients with exposure histories who are at risk of developing COPD,” he says. “This research may give us a better understanding of the trajectory of early COPD.”