Antiviral prescription of mild to moderate COVID-19 and adherence to official recommendations in Spanish emergency departments.

Objective: To analyze the prescription of antiviral therapy for mild to moderate COVID-19 in Spanish emergency departments, the incidence of missed opportunities to prescribe, and associated factors.

Methods: Retrospective cross-sectional study in 16 hospital emergency departments. We collected data for adults with mild to moderate COVID-19 confirmed within 7 days of first symptoms. The patients studied were at risk for progression and were treated as outpatients during the first 8 months of 2022. We estimated the incidence of missed opportunities and evaluated associated factors with a Bayesian statistical approach assuming noninformative prior distributions.

Results: The overall incidence of missed opportunities to prescribe was 33.5% (95% probability interval [PI], 31.7%- 35.3%). Incidences in the 16 hospitals ranged from 17.8% to 50.6%. Adjusted odds ratios (aORs) showed that factors associated with more missed opportunities were age (aOR, 1.021; 95% PI, 1.013-1.029); widening of recommended indications relative to the first period (aOR third period, 2.641 [95% PI, 1.844-3.783]; aOR fourth period, 7.440 [95% PI, 5.352-10.343]; and aOR fifth period, 17.743 [95% PI, 10.821-29.105]); immunosuppression (aOR, 2.698; 95% PI, 2.115-3.443); and fewer vaccine doses relative to no vaccination (aOR 3 doses, 0.287 [95% PI, 0.197-0-417] and aOR 4 doses, 0.115 [95% PI, 0.074-0.179]). Factors associated with increased antiviral prescription were obesity (aOR, 0.735, 95% PI, 0.567-0.952) and the existence of automated clinical pathway alerts (aOR, 0.287; 95% PI, 0.114-0.721).

Conclusions: The incidence of missed opportunities to prescribe antiviral therapy is high. Incidences vary across hospitals and more often involve the most vulnerable patients.