Too many antibodies or too little cortisol – these are possible causes of Long Covid

The fact that very few patients with Long Covid receive support from health insurers and are not taken seriously by all doctors is mainly because there is not yet a clear marker in the blood for the disease. So there is no reliable evidence to diagnose the disease with certainty. That’s going to change.

An American study led by research leader Akiko Iwasaki in August showed that those affected have only about half the level of cortisol in their blood than healthy people. The hormone is produced by the adrenal glands and inhibits inflammation in the body. It is released more in the morning and least in the early hours of the night.

Cortisol is mainly produced during stress. In the latest issue of Clinical Immunology, Greek researchers now outline how stress and long-term covid may be linked. They consider it unlikely that the interaction between the adrenal glands and the brain, the so-called hypothalamus-pituitary-adrenal axis (HPA), will become unbalanced as a result of the corona infection. However, they are only based on a study of 40 people who died of corona and had no cell damage to the adrenal glands.

The authors rather suspect that this axis was already disrupted before the infection: persistent stress and thus a constant release of the hormone could lead to cortisol losing its anti-inflammatory effect on the immune system and eventually being detected in smaller amounts in the blood. The hormone is usually elevated, at least in the acute phase of Sars-CoV-2.

In an infection like Sars-CoV-2, which can lead to inflammation anywhere in the body, too little cortisol would be devastating. This is in line with a study by the American Harvard TH Chan School of Public Health, which found that psychological stress prior to infection significantly increases the risk of lung covid.

This thesis also ties in with the fact that the doctors in the long Covid consultation hours, such as the German doctor Jördis Frommhold, have long reported that their patients are remarkably often people who ask a lot of themselves both privately and privately. professional and unite they have a full calendar of appointments. There are a striking number of reports from affected competitive athletes, but also from mothers.

A rather surprising proposition for an increased risk of long-term symptoms was shown by a US study of rheumatic patients. Long-Covid patients therefore had fewer antibodies against the Sars-CoV-2 spike protein in their blood – but more antibodies against one of the harmless coronavirus strains that have long circulated as common cold viruses.

The researchers speculate that a strong immune system memory of an ancient coronavirus may prevent the immune system from responding specifically to the novel coronavirus. This is the so-called “antigenic original sin”, a print that causes the immune system to first fall back on similar antibodies that already exist.

Although it can react more quickly, it is not very specific and also fails to produce many new, specific antibodies. This effect could also be the reason why new corona vaccines do not work better: the immune system was strongly influenced by the original Wuhan virus in three previous vaccinations. (aargauerzeitung.ch)