COVID-19 and its long-term sequelae: what do we know in 2023?

Abstract

Post-viral syndrome is a well-known medical condition characterized by different levels of physical, cogni- tive, and emotional impairment that may persist with fluctuating severity after recovering from an acute viral infection. Unsurprisingly, COVID-19 may also be accompanied by medium- and long-term clinical sequelae after recovering from a SARS-CoV-2 infection. Although many clinical definitions have been provided, “long-COVID” can be defined as a condition occurring in patients with a history of SARS-CoV-2 infection, developing 3 months from the symptoms onset, persisting for at least 2 months, and not explained by alternative diagnoses. According to recent global analyses, the cumulative prevalence of long-COVID seems to range between 9% and 63%, and is up to 6-fold higher than that of similar postviral infection conditions. Long-COVID primarily encompasses the presence of at least 1 symptom, such as fatigue, dyspnea, cognitive impairment / brain fog, postexertional malaise, memory issues, musculoskel- etal pain / spasms, cough, sleep disturbances, tachycardia / palpitations, altered smell / taste perception, headache, chest pain, and depression. The most important demographic and clinical predictors to date are female sex, older age, cigarette smoking, pre-existing medical conditions, lack of COVID-19 vac- cination, infection with pre-Omicron SARS-CoV-2 variants, number of acute phase symptoms, viral load, severe / critical COVID-19 illness, as well as invasive mechanical ventilation. Concerning the care for long-COVID patients, the greatest challenge is the fact that this syndrome cannot be considered a single clinical entity, and thus it needs an integrated multidisciplinary management, specifically tailored to the type and severity of symptoms.