Home-based management of COVID-19 by identification of low-risk features

Covid-19 is a triphasic disorder characterized by a viral phase lasting 7-10 days from first onset of symptoms. In approximately 20% it is followed by a second stage heralded by elevation of pro-inflammatory markers such as ferritin, IL-6, CRP, LDH and D-dimers. We hypothesized that those with few abnormalities would have a low risk for progression to respiratory insufficiency and could be monitored at home without treatment.

Inclusion criteria included age >21, O₂ saturation >90%. To be observed without treatment patients could not have >1 of the following: CRP > 10 mg/dL, high LDH, ferritin > 500 ng/ml, D-dimer > 1 mg/L, IL-6 > 10 pg/ml, absolute lymphocyte count <1,000, O₂ sat <94%, or CT chest evidence of pneumonia. Primary endpoint: progression to respiratory failure. Secondary endpoint: 28-day survival.

Of 208 entered, 132 were monitored without therapy. None progressed to respiratory failure or died.

We have shown that our approach can identify cases who can safely be observed without treatment, thus avoiding expensive, potentially toxic therapies, and circumventing unnecessary, costly hospitalizations. These results support our hypothesis that after applying our criteria, 64% of Covid-19 cases can be monitored as outpatients without therapy.