Bourbeau J, et al. 2022.
Ambient Air Pollution and Dysanapsis:
Associations with Lung Function and COPD in the CanCOLD Study. American Journal of Respiratory and Critical Care Medicine.
Background: Chronic obstructive pulmonary disease (COPD) exacerbations represent an important determinant of the overall burden of COPD and contribute greatly to the increasing cost of the disease. These episodes of acute symptom worsening are associated with accelerated lung function decline, impaired health status, increased hospitalization, and increased mortality. The incidence and impact of exacerbation events in persons with undiagnosed COPD within the general population is unknown.
What this study adds: This study shows for the first time that despite experiencing fewer exacerbations, health care use to treat exacerbation-like events in undiagnosed individuals with COPD is similar to that of diagnosed individuals. Consequently, COPD exacerbation events contribute much more than previously thought to the overall burden of COPD. Considering that a significant number of people remain undiagnosed with COPD, the exacerbation-like events they experience are being treated as isolated incidences without awareness of the need for future management of underlying COPD.
Marijuana is the second most common substance smoked worldwide after tobacco. Previous studies have associated marijuana exposure with increased respiratory symptoms and chronic bronchitis among long-term cannabis smokers. However, the long-term effects of marijuana smoking on lung function remain unclear.
Poor sleep quality in individuals with COPD is associated with risk of symptom-based (dyspnea or sputum change ≥ 48 h) and event-based (symptoms plus medication or unscheduled health services use) COPD exacerbations.
Background: Alpha-1 antitrypsin (AAT) deficiency (AATD) is an inherited condition characterized by low AAT serum concentrations and is associated with an accelerated rate of lung function decline, early onset emphysema and an increased risk of Chronic Obstructive Pulmonary Disease (COPD). AATD is caused by genetic mutations in the SERPINA1 gene. DNA sequencing provides a complete assessment of the mutated gene by detecting its conventional mutated alleles and its rare and novel genetic variants. Little is known about how common these deficient alleles are in the Canadian population and their individual and cumulative impacts on COPD phenotypes including lung function decline and emphysema.
What this study adds: This study shows that 15.5% of individuals of the CanCOLD cohort were carriers of at least one deficient allele affecting AAT serum levels. CanCOLD participants with genotypes resulting in severe AATD were more susceptible to develop airway obstruction, as demonstrated by lower lung function and greater emphysema. This study also shows the feasibility of DNA sequencing on a large scale to provide an accurate and definitive diagnosis for AATD. Results emphasize the advantages of genotype screening, which include allowing clinicians to make more informed treatment decisions based on more personalized risk prediction and helping to reduce the reported under-diagnosing of alpha-1-antitrypsin deficiency.