The predictors for COPD exacerbations using remote patient monitoring

Abstract

Introduction: Remote patient monitoring (RPM) averts hospitalization in chronic heart failure. Benefit from RPM in COPD is still unclear. However, early detection and treatment of COPD exacerbations should also avert hospitalization and potentially reduce healthcare expenditure.

Aims: Our aim was to identify the best parameters to monitor at home in COPD patients for the prediction of exacerbations.

Methods: We conducted a prospective study to evaluate the effects of a RPM in patients with moderate to severe COPD. We obtained daily symptom scores using a programmable device (SpiroPro^®, eResearch Technology) and measured daily spirometry (FEV₁, FVC, PEF), inspiratory capacity(IC) and oxygenation (SpO₂). Statistical process control (decrease below 7-day average-1.645 SD for 2 consecutive days) was used to detect abnormal values (predictors). Exacerbations were defined by standard criteria. Agreement between predictors and outcomes was analyzed by concordance analysis.

Results: We obtained data for 2,618 monitoring days in 11 subjects: mean(SD) age 71.1(7.2) years, FEV₁ 1.54 (0.73) L or 56.8 (15.9)% predicted. Event rates/patient-year for outcomes were: self-reported 0.42, 2/3 Anthonisen Criteria (AC) 0.42, modified AC 2.23, systemic corticosteroids use 0.56 and antibiotics use 0.56. Declines in FVC and FEV₁ predicted exacerbations that were self-reported (kappa 0.525; P<0.001). Declines in SpO₂ and increased short-acting bronchodilator use predicted exacerbations defined by 2/3 AC or modified AC (kappa 0.353 and 0.462 respectively; P<0.001).

Conclusions: We have demonstrated the feasibility of RPM in COPD patients at home and identified predictors of exacerbations that could be deployed in future health maintenance programs.