Two doses of vaccine reduce the long-term consequences of a corona infection by around 40 percent. This is the result of a meta-analysis in which British researchers evaluated what influences the development of post-Covid syndrome. This is what experts call it when symptoms such as shortness of breath, fatigue and concentration problems persist three months after infection. Long-Covid, on the other hand, is defined as complaints that last or occur between four weeks and three months after infection.
For their analysis, the team led by Vasiliki Tsampasia from the University of East Anglia in Norwich evaluated 41 studies from different countries with a total of 860,000 patients. The researchers found four studies on the effect of the vaccination, which included 250,000 patients and were all of high quality in the opinion of the authors.
Risk factors include smoking, being overweight – and being a woman
At the same time, the team identified a number of factors that favor the emergence of post-Covid. Above all, this includes the severity of the acute Covid disease. Patients who had to be treated in the clinic had an approximately 2.5-fold risk of still suffering from the consequences after three months. The researchers limit that even the long time in the intensive care unit can weaken the body. Nevertheless, patients with severe Covid courses would have a higher risk of post-Covid, write the researchers in the journal Jama Internal Medicine.
At the same time, the work confirms the finding that women are more often affected by post-Covid than men. Your risk is therefore increased by about 50 percent. The reasons are not clear; the authors point out that female hormones, among other things, could contribute to inflammatory conditions lasting longer. The team identified age over 40, obesity and smoking as further risk factors. For these factors, the post-Covid risk was increased by around 10 to 20 percent. And previous illnesses are also relevant. In particular, ailments that are associated with a restricted functioning immune system, the lung disease COPD, anxiety disorders, depression, asthma and coronary heart disease increase the probability of long-term consequences by between 20 and 50 percent, according to the evaluation.
The authors qualify that their findings come from observational studies, not all of which are of very high quality. In addition, it is not certain whether all included patients actually suffered from post-Covid, since the diagnostic criteria were not always identical everywhere. In addition, the analysis does not distinguish between different virus variants. However, the authors assume that the risk factors apply to all types of Sars-CoV-2.