Coronavirus: Kiwi doctors help rewrite the rulebook for treating COVID-19

New Zealand scientists have contributed to research which has resulted in the World Health Organization changing its recommendations on how to treat COVID-19. 

A review of a number of studies into the use of corticosteroids in critically ill patients - one of which was conducted in New Zealand - found "fewer patients died and less intensive care (ICU) support was required when patients received corticosteroids compared with usual treatment", according to the Health Research Council of New Zealand. 

The steroids in question were hydrocortisone, dexamethasone and methylprednisolone, which work by lightly suppressing the body's immune system.

"In some people with COVID, the immune system generates a hyper-response, for reasons that are not clearly understood," said Prof Greg Kyle of the Queensland University of Technology.

"This severe reaction results in the body attacking itself and generating severe symptoms and death. The steroids calm this reaction down - just like pruning a hedge. We don't want to kill the hedge (that is, completely stop the immune system), we want to trim it back so it is not running rampant, but rather is controlled and still able to function."

The studies, done in 12 countries, involved 1703 patients. Of those, 678 got corticosteroid, and the rest a placebo or usual care. 

"Of those randomised to corticosteroids there were 222 deaths and 456 survivors, compared to 425 deaths and 600 survivors of those randomised to usual care or placebo," the Health Research Council said.

"That equates to over 20 percent fewer deaths," said Auckland City Hospital's Colin McArthur, co-author of the review.

Christopher Gale from the Otago Medical School told Newshub the findings will make a real difference to treatment worldwide, calling them a "game-changer". 

"I think it's part of the puzzle for dealing with the most sick people. I think that group  of people, often we're using multiple treatments at once." 

Research in the UK from July found dexamethasone was effective, and the discovery of other steroids like hydrocortisone work too will relieve pressure on supply chains.

"We've now confirmed that hydrocortisone is an acceptable alternative to dexamethasone," said Dr McArthur. "I don't think there's going to be any question now about corticosteroids being the standard of care."

Kiwi researchers will soon be looking into other possible treatments, including convalescent plasma, anticoagulation and antiplatelet treatments.

The new findings are now part of the WHO's new clinical practice guidelines for treating people severely ill with COVID-19, which has killed at least 864,000 people worldwide this year, and left many survivors struggling with the after-effects for months.

"The result is robust and we can now confidently state that corticosteroids should be used in critically ill patients with respiratory failure due to COVID-19," said Ian Seppelt, intensive care specialist at Australia's Nepean Hospital.

"There remain questions of which steroid should be used and precisely what dose should be used, and future research should be targeted to answer these questions."

The research was published in journal JAMA.