The following is a summary of “Defining the Role of Exertional Hypoxemia and pulmonary vasoconstriction on Lung Function Decline, morbidity, and Mortality in Patients with Chronic Obstructive Lung Disease – the PROSA Study: rationale and Study Design,” published in the May 2024 issue of Pulmonology by Böger et al.
Chronic obstructive lung disease (COPD) encompasses a range of molecular pathomechanisms and clinical trajectories that are not adequately addressed by existing therapeutic strategies. Intermittent hypoxemia is recognized as a significant factor contributing to lung function deterioration and adverse outcomes, particularly in patients who also suffer from obstructive sleep apnea. Recent evidence suggests that transient hypoxemia experienced during physical exertion may similarly impact disease progression. The PROSA study is a prospective investigation designed to determine whether the clinical trajectories of patients with COPD with exertional desaturation differ from those without while also exploring potential pathophysiological mechanisms and identifying relevant biomarkers.
In this study, 148 patients with COPD classified as GOLD stage 2 or 3 (Groups B or C) will participate in exercise testing, including continuous pulse oximetry monitoring.
Participants will be monitored over 36 months through spirometry, echocardiography, assessments of endothelial function, and biomarker analysis. Exercise testing will involve the 6-minute walk test (6MWT), bicycle ergometry, and a 15-second breath-hold test. Exertional desaturation will be defined by an oxygen saturation (SpO2) level of less than 90% or a delta-SpO2 change of 4% or greater during the 6MWT. The primary endpoint of this study is the rate of decline in forced expiratory volume in one second (FEV1) measured against the lower limit of normal (LLN) in patients with COPD categorized by the presence or absence of exertional desaturation.
The PROSA study aims to substantiate or refute the hypothesis that patients with COPD experiencing exertional desaturation exhibit a significantly more accelerated decline in lung function compared to non-desaturation. A clinically significant difference of 20% in the primary endpoint is anticipated, with a power of 90% to detect such differences. Should the primary endpoint be validated, exercise testing with continuous pulse oximetry may emerge as a practical screening tool to identify patients with COPD at risk for rapid lung function decline early in the disease course. This early identification could facilitate the implementation of personalized, risk-adapted therapeutic strategies to improve long-term outcomes in COPD. The PROSA study is funded entirely by public resources provided through an ERC Advanced Grant from the European Research Council, with patient recruitment currently underway and results expected by 2028.
Source: bmcpulmmed.biomedcentral.com/articles/10.1186/s12890-024-03074-x