Can long-term post-COVID-19 fainting syndrome explain why a US artist swimmer Anita Alvarez has recurrent fainting attacks after diving during a swimming competition? Does interleukin-6 play a role?
Authors: Ahmed Amr , Alaa Neveen 
Published: September 2022

At the 19th FINA (Fédération Internationale De Natation.) World Aquatic Championships were held in Budapest, Hungary, American swimmer Anita Alvarez lost consciousness, experienced recurrent fainting attacks after diving during a swimming competition, and had to be pulled from the bottom of the pool by her coach. And this happens for the second time (1)Five (0.6%) of the 789 elite athletes in an observational study who tested positive for COVID-19 had CMR evidence of inflammatory cardiac disease (myocarditis or pericarditis) (2) Concern has been expressed by a number of authors on the effect of neurologic and neuromuscular problems on return to play. As they recover from COVID19 disease, athletes may experience tiredness, decreased neuromuscular function, and decreased muscle strength. Several additional COVIDrelated problems, such as general weariness, cognitive impairment, and coagulopathy, can occur in recovering athletes. (3)(4)The most common chronic cardiovascular dysautonomia in young and middle-aged people, primarily women, is postural orthostatic tachycardia syndrome (POTS). Chronic orthostatic intolerance, an abnormal increase in heart rate (HR) upon standing, and deconditioning are its defining characteristics. Post-viral autoimmune activation has been proposed as a potential cause of the condition (5) Interleukin-6 is crucial for athletes, particularly after arduous activity and after submerging in cold water. Immersion in cold water is linked to a little increase in IL-6 levels from post-exercise values. (6) Two studies described a syncopal episode in COVID-19 survivors 3 to 4 weeks after diagnosis, at the post-acute COVID-19 stage. This increases the likelihood that syncope had a role, not just during the illness's acute stage but also as a long-term consequence. Patients in both of these cases underwent analysis for postural orthostatic tachycardia disorder, a part of the autonomic dysfunctions. As previously stated, unexplained pre/syncope accounted for 87.9% (531/604) of the detailed scenes and was the most frequent cause of the temporary loss of awareness. Reflex pre/syncope occurred 7.8% of the time overall (47/604). Orthostatic hypotension made up 2.2 percent (13/604) of the cases, and 2.2 percent (13/604) of the cases likely had cardiac pre/syncope. (7,8)Interleukin-6 (IL-6) is a localized energy sensor that is supplied to active skeletal muscle and can explain why there is an increase in plasma IL-6 during exercise. The length and intensity of the workout have an impact on the creation of IL-6, and moo muscle glycogen material supports this production. The discovery of abnormally elevated levels of IL-6 following arduous exercise has consistently been observed in several studies. After 6 minutes of vigorous exercise, a 2-fold increase in plasma IL-6 was seen. After 30 minutes of running by the treadmill, the blood level of IL-6 had significantly increased, reaching its peak after 2.5 hours. In other studies, when IL-6 levels weren't monitored during the running workout but rather a few hours later, peak IL-6 levels were discovered right away after the workout, followed by a rapid decline. In this manner, maximal IL-6 levels (100-fold increment) were assessed immediately following the 3-3.5 h race. (9) Peak IL-6 levels are attained at the conclusion of the workout or soon after. Chronic IL-6 elevations cause hyperinsulinemia, lower body mass, and impaired insulin control of skeletal muscle glucose absorption. The level of circulating IL-6 is two to three times higher in senior patients with type 2 DM than it is in younger, healthy people. (10) As stated by NICE (National Institute for Health and Care Excellence), A significant proportion of acute COVID-19 survivors experience long-term physical and neuropsychiatric symptoms, which are categorized as "ongoing symptomatic COVID-19" (symptoms that continue for 4 to 12 weeks after the onset of the illness) and "post-COVID-19 syndrome" or "long COVID" (symptoms that continue for more than 12 weeks). We hypothesize that inflammatory cytokines like interleukin-6 may be involved in the neuro-immune cross-talk that results in these chronic COVID-19 symptoms (IL-6). This hypothesis is supported by a number of research lines, including population-based cohort and genetic Mendelian Randomization studies, which suggest that inflammation and weariness are related and that IL-6 may play a causal role in both symptoms. In particular, clinical epidemiology studies are necessary to determine whether IL-6 and/or other inflammatory cytokine levels are elevated. (11) Finally, this letter of the editor is an alarming pill for saving athletes all over the world and evaluating recurrent attacks of syncopal or cardiac arrest or other cardiovascular problems nowadays post covid-19 pandemic long-term sequelae, and more clinical studies are needed.