COVID-19 survivors who were not sick enough to be hospitalized still had a significantly higher risk of death within months of their diagnosis compared to those unaffected, according to a new U.S. study.   

The research was conducted by Washington University's School of Medicine in St. Louis, Missouri. It compared some 87-thousand COVID-19 patients registered with the U.S. Veterans Health Administration(VHA) to nearly five million VHA patients who were not diagnosed with the virus. 

The study found that those who were sick with COVID-19 for at least 30 days had an almost 60 percent increased risk of death in the following six months compared with those without the virus.  

Eight out of one-thousand COVID-19 survivors were found to have died from the effects of the infection within six months of their diagnosis, while the likelihood surged to 29 deaths out of one-thousand for those who were ill enough to be hospitalized. 

The study, published on the scientific journal Nature's website Thursday, assessed that a COVID-19 infection - although a respiratory disease - can affect other organ systems in the body if it is protracted.