Lungs, kidneys, heart: what are the complications of Covid-19?

In 80% of cases, the symptoms of Covid-19 remain mild and moderate and disappear in a maximum of 14 days. However, in some patients, especially those at risk, respiratory discomfort linked to the accumulation of fluid in the bronchioles can lead to a lack of blood oxygenation and require hospitalization.

It can also happen that other complications related to Covid-19 appear. What are they ? For the first time, a large study of American patients who have contracted Covid-19 provides an overview of the complications of the disease. Published in the CMAJ (Canadian Medical Association Journal), it confirms what previous smaller studies have already suggested: Covid-19 not only affects lung health, but can also seriously damage the kidneys and undermine the immune system.

Pneumonia, the first complication of Covid-19

To reach this conclusion, the researchers identified 70,288 patients who consulted for Covid-19 between 1^er March and April 30, 2020 by sifting through claims for reimbursement of medical expenses. More than half of the patients were admitted to hospital during this period, and about 5% were admitted to the intensive care unit. The median age was 65, and 55.8% were female. The authors looked at all possible diagnostic codes and identified those that increased in frequency after the onset of Covid-19.

It turned out that the most common complications associated with Covid-19 were pneumonia and respiratory failure, but also kidney failure, sepsis or systemic inflammation, which is consistent with other studies.

The absolute risk of someone with Covid-19 having these serious conditions was 27.6% for pneumonia, 22.6% for respiratory failure, 11.8% for kidney failure and 10 .4% for sepsis or systemic inflammation.

Associations with a range of other pulmonary and cardiovascular conditions have also been found. This is the case with pulmonary collapse (a collapse of the lungs), blood clotting disorders and heart inflammation, although the risk is relatively low.

On the other hand, contrary to the results of other studies, this new work does not establish a link between Covid-19 and a higher risk of stroke.

According to the authors of the study, this “provides estimates of absolute risk and relative odds for all identified diagnoses related to Covid-19, which are needed to help providers, patients, and policy makers understand the likelihood of complications”. Better understand all the conditions associated with the new coronavirus “may help establish a prognosis, guide treatment decisions and better inform patients about their real risks for the various complications of Covid-19 reported in the literature and the media”concludes Dr. William Murk, co-author of the study.