Canadian Cohort Obstructive Lung Disease (CanCOLD): Fulfilling the Need for Longitudinal Observational Studies in COPD

Abstract

Awareness, diagnosis and treatment of COPD, compared to other major causes of death, remains far too low. This article describes the protocol objectives, design and the approaches taken in the Canadian Chronic Obstructive Lung Disease (CanCOLD) study, an epidemiological and integrated research. The CanCOLD study aims at better understanding heterogeneity of COPD presentation and disease progression. We hypothesize that individuals with unfavourable COPD "phenotypes" and subjects at-risk (ever smokers) with unhealthy lifestyle habits, environmental/work exposure, or co-morbidities will have increased risk of lung function decline independent of their cumulative exposure to cigarette smoke. The study is a prospective multi-center cohort study (9 sites in 6 provinces) built on the Canadian COPD prevalence study "COLD." The study plan is to include 1800 subjects at least 40 years old who were sampled from the general population and who were found to fall within 4 groups: 1) COPD moderate-severe (GOLD 2-4); 2) COPD mild (GOLD 1); 3) subjects at-risk (ever smoker); and, 4) subjects never-smoker free of airflow obstruction. Data collection is based on using strictly standardized methods involving questionnaires, pulmonary function and cardiorespiratory exercise tests, CT scans, and blood sampling. CanCOLD is a unique study that will address challenging and important research questions on COPD disease evolution and disease management and will help to define the natural history of COPD disease evolution in individuals at-risk for COPD and in those with COPD who have mild disease.

A Novel Method of Estimating Small Airway Disease Using Inspiratory-to-Expiratory Computed Tomography

“…Participants between 45 and 90 years from the multisite, population-based CanCOLD study were evaluated [12,13] ; the sites include Vancouver, Calgary, Ottawa, Quebec City, Montreal, Toronto, Halifax, Kingston, and Saskatoon. Ethics approval was obtained from the institutional review board at each CanCOLD study site.…”

“…CT images were acquired at multiple sites using various CT system makes and models with the participant supine at suspended full inspiration and full expiration from the apex to the base of the lung [13] . The CT parameters for image acquisition in the participants investigated were as follows: 100 kVp, 50 mAs, 0.5 s gantry rotation, pitch of 1.375, 1.00-1.25 mm slice thickness, and an intermediate reconstruction kernel (GE: Standard; Siemens: b35; Philips: B) was used for quantitative analysis.…”

The COPD Assessment Test

“…Detailed descriptions of the sampling strategy and assessments can be found in the published protocol. 6 Because the CanCOLD study is ongoing, subjects are currently being recruited while others are in the follow-up period. Therefore, some of the subjects included at the time of this analysis (May 2016) had not yet completed their visits at 1.5 or 3 years and M A N U S C R I P T…”

“…6,7 The cohort comprises two balanced COPD subpopulations (GOLD 1 and GOLD ≥2) and two age-and sexmatched non-COPD subjects (ever-smoker for those at risk and never smoker for the healthy controls, e.g., post bronchodilator FEV 1 /FVC >0.70). Only those patients with spirometrically confirmed COPD were selected from the CanCOLD cohort for the current study.…”

SPIROMICS Protocol for Multicenter Quantitative Computed Tomography to Phenotype the Lungs

“…There are several large multicenter studies of both COPD and asthma that include QCT to evaluate changes in the lung, including the Multi-Ethnic Study in Atherosclerosis (MESA) Lung Study (9), the Evaluation of COPD Longitudinally to Identify Surrogate Endpoints (ECLIPSE) study (10), the Genetic Epidemiology of COPD study (COPDGene) (11), the Canadian Cohort of Obstructive Lung Disease (CanCOLD) study (12), and the Severe Asthma Research Program (SARP) (13).…”