Differential impact of the pandemic first wave on chronic respiratory diseases in France

Background . The COVID-19 pandemic has been associated with dramatic changes in the management of patients with chronic respiratory diseases (CRD), resulting in varying clinical profile and use of healthcare services of patients hospitalised. Patients and Methods . Using the French national hospital database, we analysed changes in epidemiological profile, clinical presentation at hospital referral and outcomes (ICU admission and in-hospital mortality) of CRD patients hospitalised for COVID-19 during the first wave of the pandemic in France. Results . Non-interstitial CRD and pulmonary vascular diseases (PVD) were the most prevalent CRDs (95%). The part of CRD patients among the total inpatients was substantial, decreasing during lockdown (from 12.1% to 10.8%), then returning to the pre-lockdown level (12.4%). The CRD patients were older and comorbid males with higher rates of ICU admission and mortality, as compared with their counterparts. Half of them had a complicated clinical profile (CCP, ICU admission or death). Overall, in-hospital length of stay was 9 (4-16) days and mortality rate 19.8%. These characteristics varied along time. In multivariable analyses, PVD was associated with a CCP (aORs, from 1.36; CI 1.18-1.57 to 1.82; CI 1.56-2.12) and mortality (with aHRs >1.5 in the 18-55 and 56-75 age groups). Conclusion . We report a substantial part of CRD patients hospitalised with COVID-19, characterized by a more severe initial clinical presentation and higher rates of complicated stays, with changes along time suggesting differential exposure and use of resources. The PVD subgroup was independently associated with CCP and mortality during the entire study period.