Patients who survive severe COVID-19 may have more than twice the risk of dying over the following year, compared with those who experience mild or moderate disease or remain uninfected, according to a study published on Wednesday. The researchers found that the increased risk of dying was greater for patients who are under 65, and only 20 per cent of the severe COVID-19 patients who died did so because of typical COVID-19 complications, such as clotting disorders or respiratory failure.
The research, published in the journal Frontiers in Medicine, suggests that severe COVID-19 may significantly damage long-term health and highlights the importance of preventing severe disease through vaccination. “We conducted a previous study which showed that patients with severe COVID-19 who recovered were at significantly greater risk of being hospitalised in the subsequent six months,” said Professor Arch Mainous of the University of Florida, US, lead author on the study.
“This new study extended that to investigate mortality risk over the next 12 months,” Mainous said. The researchers tracked electronic health records of 13,638 patients who underwent a PCR test for COVID-19, with 178 patients experiencing severe COVID-19, 246 mild or moderate disease and the rest testing negative.
All patients included in the study recovered from the disease, and the researchers tracked their outcomes over the next 12 months. The study found that patients who had recovered from severe COVID-19 had a significantly greater chance of dying over the next year, compared with those who were uninfected or experienced mild or moderate disease.
Some surprising trends emerged from the data, with severe COVID-19 patients aged under 65 demonstrating a 233 per cent increased chance of dying, compared with the uninfected, the researchers said. This was larger than the increased chance of dying experienced by severe COVID-19 patients aged over 65, compared with the uninfected, they said.
The researchers noted that as these deaths frequently occurred long after the initial infection had passed, they may never have been linked to COVID-19 by the patients’ families or doctors. Most of the deaths that occurred in severe COVID-19 survivors were not linked with common complications from the disease, such as respiratory or cardiovascular issues, according to the researchers.
In fact, 80 per cent of such deaths occurred for a wide variety of reasons that are not typically associated with COVID-19, they said. This, the researchers said, suggests that the patients had experienced an overall decline in their health that left them vulnerable to various ailments.
Mild or moderate COVID-19 patients did not have a significantly increased mortality risk compared with the uninfected, highlighting the importance of reducing the chances of severe disease through vaccination, they explained. “Since we now know that there is a substantial risk of dying from what would likely be considered to be an unrecognised complication of COVID-19, we need to be even more vigilant in decreasing severe episodes of COVID-19,” said Mainous.
“Taking your chances and hoping for successful treatment in the hospital doesn’t convey the full picture of the impact of COVID-19. Our recommendation at this point is to use preventive measures, such as vaccination, to prevent severe episodes of COVID-19,” he added.