Most people in their advance age, especially among those who are infected by the novel coronavirus and are suffering from some underlying disease such as hypertension, diabetes, heart disease, and obesity, have lower rates of survival, even if they are put on ventilators, a study said.
The Washington Post cited the study, published in the Lancet, on Tuesday, saying that most elderly Covid-19 patients put on ventilators at two New York hospitals did not survive.
"We had no idea how horrific this would be," Max O''Donnell, the senior author of the study and a pulmonologist at Columbia University Irving Medical Center, was quoted by the Post.
"Definitely not just the flu," he added.
The research focused on 257 critically ill adults, representing a little under one-quarter of the confirmed coronavirus patients admitted at the two hospitals in northern Manhattan between March 2 and April 1. The median age of critically ill patients was 62 years, and two-thirds of them were male.
Of the critically ill patients studied, 39 per cent had died by April 28, and 37 per cent remained hospitalised at Milstein and Allen hospitals.
No critically ill patients under the age of 30 died at the two hospitals, O'Donnell said, and only a small number of them had to be put on ventilators. But more than 80 per cent of people over 80 who went on a ventilator did not survive, he said.
That fact, he said, should be shared with elderly patients and their family members when trying to decide whether to use the invasive procedure to treat severe illness associated with covid-19, the disease caused by the novel coronavirus.
"It's a difficult conversation, obviously," O'Donnell said further.
In the second finding, the study also said that discharge and mortality rates for the most critically ill patients have varied widely among hospital systems.
Doctors told the Post that mortality rates -- which range from 50 per cent to 97 per cent in published studies -- probably reflect different regions'' demographics and the varied treatment practices in the early days of the outbreak when doctors were writing and rewriting treatment protocols on the fly almost every day.
"The mortality rate [for patients on ventilators] creeps up to 70 per cent when you''re over the age of 70," Thomas McGinn, deputy physician in chief at Northwell Health, said Tuesday, told the Lancet.
"If your mom's 85 and not well, they should know what the potential is for surviving before they have a ventilator placed," he added.
The study further appeared to confirm associations between a patient''s risk of death and markers for inflammation and coagulation in laboratory analyses of their blood samples. Doctors have been reporting in recent months that some covid-19 patients are suffering from clots that can lead to strokes or respiratory arrest.
The obesity rate is among the striking features of the new research. Among critically ill patients under the age of 50 who were admitted to the hospitals, 71 per cent were obese.
Harlan Krumholz, a professor of medicine at Yale School of Medicine, said the Lancet study "gives a perspective on the devastating nature" of covid-19, and "should give pause to anyone who wants to dismiss SARS-CoV-2 as less than a major threat to health."
Covid cases globally surpassed 5 million on Wednesday, with Latin America overtaking the United States and Europe in the past week to report the largest portion of new daily cases globally.
Latin America accounted for around a third of the 91,000 cases reported earlier this week. Europe and the United States each accounted for just over 20 per cent, representing a new phase in the virus'' spread, which initially peaked in China in February, before large-scale outbreaks followed in Europe and the United States.
A large number of those new cases came from Brazil, which recently surpassed Germany, France, and the United Kingdom to report the third-largest novel virus outbreak, behind the United States and Russia, across the globe.
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