Health significance of the COVID-19 pandemic for patients with primary ciliary dyskinesia

<bold>Rationale:</bold> Amid the COVID-19 pandemic , Denmark enforced a comprehensive lockdown. For patients at the Danish PCD Center stringent health measures were advised. This study aimed to explore the impact on patient health. <bold>Methods:</bold> This single center cohort study included patients with genetically verified primary Ciliary Dyskinesia (PCD) at the national Danish PCD Center in Copenhagen. Data from March 2019 to March 2022 was extracted from electronic medical records. Information on SARS-COV-19 testing and vaccinations, hospital visits, COVID-19 morbidity, including lung function (FEV1) measurements before and during lockdown, and mortality. Patients with a positive SARS-COV-19 test completed a symptom questionnaire. Public data on the background population (BP) was used for comparison. <bold>Results:</bold> Eighty-six out of 131 (66%) Danish children and adults with PCD were included (44% male, mean age 30, range 2 to 82 years). 21% (18) tested positive for SARS-COV-19 in the period, which contrasted with 58% in the BP (P < 0.0001). 88% (76) accepted vaccination. Seven percent were asymptomatic, while 93% had various mild COVID-19 symptoms. Only one (1%) with PCD was admitted to hospital, recovering in 4 days without intensive care. In contrast a total of 2% had been admitted within the BP (P = 0.5). The mortality in the BP was 0.2% while nobody died within the PCD cohort (P = 0.68). FEV1 z- did not change with time (0.08/year, p = 0.3225), nor between isolation periods (p = 0.1344). <bold>Conclusion:</bold> The lockdown along with self-isolation, testing and vaccination significantly reduced COVID-19 infection rates among PCD patients, with minimal health impact and no mortality. Lung function remained stable.