What is Postcoid Syndrome
Long covid or postcoid syndrome is not one specific consequence of infection. According to the British National Institute for Health and Care Excellence (NICE), these are “signs and symptoms that develop during or after COVID-19 that last longer than 12 weeks and cannot be explained by other causes.” If symptoms last 4-12 weeks, the institute qualifies it as “ongoing symptomatic COVID-19”.
The fact that the consequences of the postponed COVID-19 can be felt over time is already well known. In the new study, the researchers aimed to find out which organs and how often are affected in patients who were treated for this infection in a hospital.
New Evidence for Postcoid Syndrome
In the new study, scientists analyzed the health of nearly 48,000 people who were hospitalized for COVID-19 in the UK for an average of 140 days.
During the observation period, 29.4% of the patients were hospitalized again, and 12.3% died. Scientists have calculated that the risk of re-hospitalization and death within a year after COVID-19 is 2.5 and 7.7 times higher than in the control group, respectively. The control group included patients who were hospitalized for other reasons.
Most often, patients had diseases of the respiratory system – in 29.6% of people, in 12.7% they were diagnosed for the first time. It is estimated that for 1,000 people discharged from hospital after COVID-19 during the year:
- diabetes mellitus develops in 29;
- severe complications from the cardiovascular system (myocardial infarction, stroke, severe heart failure, and others) are observed in 66;
- chronic kidney disease was registered in 15;
- chronic liver disease develops in 4.
These complications in the group of COVID-19 patients appeared 1.5-3 times more often than in the control group. Postcoid syndrome was more common in people over 70 years old.
Scientists emphasize that after discharge, patients may have lesions of various organs. Therefore, doctors of different specialties will have to deal with the diagnosis and treatment of the postcoid symptom. They point out that it is necessary to establish risk factors for postcoid syndrome so that treatment can be more targeted.
What was known about postcoid syndrome before
Previously, scientists made assumptions that explain the possible mechanisms of long covid: from the respiratory and cardiovascular systems, kidneys and liver, metabolism. However, the review authors, published in December 2020, point out that knowledge about the condition is limited and mostly based on low-quality evidence.
One previous study found that of 1,775 people hospitalized with COVID-19,% were re-hospitalized, and 9% died within 60 days. These findings are consistent with the results of the new study, if the follow-up period is shortened to an appropriate length. But the old study did not provide data on organ damage.
Other scientific papers – usually of a smaller size – have produced results that differ from the new data. In a study involving 213 people who were discharged from their hospital after treatment with COVID-19, 10% of patients returned to the hospital within 80 days, 2% died. These results – much less than in the new large study – could be attributed to the small number of participants.
A 140-day follow-up of 201 low-risk patients found lung lesions in 33% of the participants, heart disease in 32%, kidney disease in 12%, and liver disease in 10%. This is significantly more than in the new study. However, the changes on the part of these organs were relatively mild, and therefore could be asymptomatic.
Several other studies provide information on what physiological changes in organs can be the cause of postcoid syndrome. One of them showed that patients after COVID-19 more often than after the flu develop acute kidney damage, myocarditis, arrhythmia, stroke, and there is a need for insulin administration. After three weeks of follow-up, patients from Wuhan were found to have lung damage, and several studies showed cardiac abnormalities.