Mechanical ventilation and mortality
Male sex, age older than 40 years, obesity, and presence of cardiovascular or chronic kidney disease were risk factors for mechanical ventilation.
Among the nearly 2,000 hospitalized adults requiring mechanical ventilation in the current report, only 27% were discharged alive. “The outcomes of people who are mechanically ventilated are really quite sobering,” Brown said.
People who ever required mechanical ventilation were 32 times more likely to die compared with others whose highest level of oxygenation was low-flow, high-flow, or no-oxygen therapy in an analysis that controlled for demographics and comorbidities.
Furthermore, patients placed on mechanical ventilation earlier – within 24 hours of admission – tended to experience better outcomes.
COVID-19 therapies?
Brown and colleagues also evaluated outcomes in patients who were taking either remdesivir or hydroxychloroquine. A total of 48 people were treated with remdesivir.
The four individuals receiving remdesivir who died were among 11 who were taking remdesivir and also on mechanical ventilation.
“The data for remdesivir is very encouraging,” Brown said.
Many more participants were treated with hydroxychloroquine, more than 4,200 or 36% of the total study population.
A higher proportion of people treated with hydroxychloroquine received mechanical ventilation, at 25%, versus 12% not treated with hydroxychloroquine.
The unadjusted mortality rate was also higher among those treated with the agent, at 25%, compared to 20% not receiving hydroxychloroquine.
The data with hydroxychloroquine can lead to two conclusions, Brown said: “One, it doesn’t work. Or two, it doesn’t work in the way that we use it.”
The researchers cautioned that their hydroxychloroquine findings must be interpreted carefully because those treated with the agent were also more likely to have comorbidities and greater COVID-19 disease severity.
“This study greatly contributes to understanding the natural course of COVID-19 infection by describing characteristics and outcomes of patients with COVID-19 hospitalized throughout the US,” the investigators note. “It identified categories of patients at greatest risk for poor outcomes, which should be used to prioritize prevention and treatment strategies in the future.”
Some limitations
“The findings that patients with hypertension and who were smokers had lower ventilation rates, and patients with hypertension, pulmonary disease, who were smokers had lower mortality risks was very surprising,” Ninez A. Ponce, PhD, MPP, told Medscape Medical News when asked to comment on the study.
Although the study identified multiple risk factors for ventilation and mortality, “unfortunately the dataset did not have race available or disease severity,” said Ponce, director of the UCLA Center for Health Policy Research and professor in the Department of Health Policy and Management at the UCLA Fielding School of Public Health.
“These omitted variables could have a considerable effect on the significance, magnitude, and direction of point estimates provided, so I would be cautious in interpreting the results as a picture of a nationally representative sample,” she said.
On a positive note, the study and dataset could illuminate the utility of medications used to treat COVID-19, Ponce said. In addition, as the authors note, “the data will expand over time.”
Brown has reported receiving grants and consulting for Gilead. Ponce has disclosed no relevant financial relationships.
This article first appeared on Medscape.com.