The pandemic of COVID-19 has caused millions of infections worldwide and the numbers are skyrocketing due to the quick-spreading omicron variant this winter. It is well known that severe COVID-19 infections led to impairment of pulmonary, cardiac, and renal functions as well as thromboembolism. However, little is known about the consequences of mild to moderate COVID-19 infections. Do they leave any traces on these important organs in our body? Unfortunately, the answer to this question from the Hamburg City Health Study (HCHS) is yes.
A total of 443 participants from HCHS, aged between 45 and 74 and have recovered from mild or moderate COVID-19 infections, have been examined extensively at the University Medical Center Hamburg-Eppendorf (UKE). The control group that was matched by age, sex, educational status came from the same season and included an additional set of 1328 HCHS participants without COVID-19 infections. The data sets were comprehensive and included magnetic resonance imaging of the heart and brain in both the COVID-19 affected subjects as well as the control group allowing for cross-organ analysis.
Even mild to moderate courses of COVID-19 affected heart, lung and kidney functions in the medium term, and they were associated with more frequent signs of previous leg vein thrombosis. In the lung function test, approximately 3% reduction in lung volume and a slight increase in airway resistance were observed in the COVID-19 participants. In the heart examinations, the affected participants showed an average of 1-2% decrease in pumping force and a 41% increase in NT-proBNP level, which is a blood biomarker and provides information about the strain on the heart. In the ultrasound examinations of the legs, signs of a previous leg vein thrombosis in affected participants were 2-3 times more frequently compared to the controls. Roughly 2% decrease in kidney function was found in the affected participants. No deterioration was identified regarding brain functions. The finding that even a mild course of the disease can lead to damage of various organs in the medium term is of utmost importance, especially with regard to the current omicron variant, which seems to be associated with milder symptoms in the majority of cases.
This work was recently published in the European Heart Journal with contributions from Cardio-CARE.
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