Effect of COVID-19 on Bronchiectasis Exacerbation Rates: A Retrospective US Insurance Claims Study.

Bronchiectasis is a chronic, progressive disease of bronchial dilation, inflammation, and scarring leading to impaired mucociliary clearance and increased susceptibility to infection. Identified causes include previous severe respiratory infections. A small, single-center UK study demonstrated a reduction in bronchiectasis exacerbations during the first year of the COVID-19 pandemic. No studies have been conducted in a US (commercially insured) cohort to date. To explore the impact of the COVID-19 pandemic on the frequency of exacerbations in a large cohort of commercially insured US patients with bronchiectasis by testing the hypothesis that US patients with bronchiectasis had fewer exacerbations during the pandemic. This retrospective observational cohort study used health insurance claims data from Optum's deidentified Clinformatics® Data Mart Database, which included US patients and their covered dependents. Eligible patients were aged 18 years with bronchiectasis; patients with other respiratory conditions were excluded. The main study cohort excluded patients with frequent asthma and/or chronic obstructive pulmonary disease diagnoses. The primary objective was to compare the bronchiectasis exacerbation rate prior to and during the COVID-19 pandemic. The median number of exacerbations per patient per year decreased significantly from the year prior to the COVID-19 pandemic to the first year of the pandemic (1 vs. 0, P < 0.01). More patients had zero exacerbations during the first year of the pandemic than the year prior (57% vs. 24%, McNemar's chi-squared = 122.56, P <0.01). In a U.S. population-based study of patients with ICD codes for bronchiectasis, the rate of exacerbations during year 1 of the COVID-19 pandemic was reduced compared with the 2-year time period preceding the pandemic. Primary Source of Funding (if any): AstraZeneca (Cambridge, UK).