Impact of the COVID-19 outbreak on acute stroke treatment in Switzerland

Background and Aims: In Switzerland, the COVID-19 incidence during the first pandemic wave was higher than in neighbouring countries including Italy. We aimed to assess the impact of the first national lockdown in the spring 2020 on acute stroke care in Switzerland. Methods: Retrospective analysis based on the Swiss Stroke Registry, which includes consecutive patients with acute cerebrovascular events (ischemic stroke, intracerebral hemorrhage and TIA) admitted to Swiss Stroke Units and Centers.We compared the hospitalization rates, patient characteristics and 3 months outcomes between the time epoch spanning from 13.03.-26.04.2020 (defined as “lockdown”) to the same epochs in 2018 and 2019. Results: Overall, 4491 patients were included. During the lockdown, the weekly hospitalization rates decreased by up to 22% compared to 2018/ 2019 (Figure). During 3 consecutive lockdown weeks, the hospitalization rates fell below the 5% quantile (likelihood 0.38%). As event type, the proportion of intracerebral hemorrhage (ICH) increased from 7.1% to 9.3% (P=0.006). A trend towards less severe strokes was observed (median NIHSS from 3 to 2, P=0.07). There was no significant change in age, onset-to-door time, use of recanalization therapies, door-toneedle/-groin times, functional outcome and mortality at 3 months. Conclusions: The observed national decrease of admission for cerebrovascular events in Switzerland during the lockdown is not explained by milder stroke severity staying at home. The decrease concerned ischemic more than hemorrhagic strokes, but acute stroke care and long term outcome remained unchanged from the pre-pandemic times.