Grant: CIHR Fellowship

Chronic obstructive pulmonary disease (COPD) is characterized by progressive loss of lung function causing shortness of breath, cough and sputum production. It affects 1.7 million Canadians, and is responsible for 11,000 deaths, and over 70,000 hospital admissions annually in Canada. Most of its burden is due to "lung attacks". These acute exacerbations of COPD (AECOPD) are often triggered by respiratory infections. AECOPD management has not changed much in the last 30 years, and available therapies remain modestly effective. Moreover, unlike heart attacks, there are no simple blood biomarkers (measureable indicator of a biological state) available for AECOPD. As a result, AECOPD is generally a diagnosis of exclusion, and misdiagnosis and severe diagnosis delays are common, leading to poor outcomes for patients. A simple reliable blood test for AECOPD would be a game-changer and enable clinicians to promptly and accurately identify these early in their course when treatments are most effective. This study will assess whether there are novel blood biomarkers that are diagnostic of AECOPD that could be used in the clinical setting. We will be evaluating biomarkers in blood samples collected at several time points in 250 COPD patients who were hospitalized with AECOPD between 2012-2014. These will be compared to 75 "control" samples collected from COPD patients who were not hospitalized and considered to be clinically stable at blood draw, and then replicated in 150 COPD patients who were likewise hospitalized with AECOPD at a different hospital. The amount of different biomarkers and how they change over time after AECOPD will be measured using commercially available kits and more complex arrays that can detect differences in gene expression. This study will investigate novel biological pathways that are most plausible biomarker candidates with the aim of developing an assay that can easily be used clinically, ultimately facilitating the diagnosis of AECOPD.