Long COVID, a comprehensive systematic scoping review

Akbarialiabad, Hossein; Taghrir, Mohammad Hossein; Abdollahi, Ashkan; Ghahramani, Nasrollah; Kumar, Manasi; Paydar, Shahram; Razani, Babak; Mwangi, John; Asadi-Pooya, Ali A.; Malekmakan, Leila; Bastani, Bahar

PURPOSE: To find out what is known from literature about Long COVID until January 30, 2021. METHODS: We undertook a four-step search with no language restriction. A preliminary search was made to identify the keywords. A search strategy of all electronic databases resulted in 66 eligible studies. A forward and backward search of the references and citations resulted in additional 54 publications. Non-English language articles were translated using Google Translate. We conducted our scoping review based on the PRISMA-ScR Checklist. RESULTS: Of 120 papers, we found only one randomized clinical trial. Of the 67 original studies, 22 were cohort, and 28 were cross-sectional studies. Of the total 120 publications, 49.1% focused on signs and symptoms, 23.3% on management, and 10.8% on pathophysiology. Ten publications focused on imaging studies. The results are also presented extensively in a narrative synthesis in separated sections (nomenclature, diagnosis, pathophysiology, risk factors, signs/symptoms, management). CONCLUSIONS: The controversies in its definition have impaired proper recognition and management. The predominant symptoms were: fatigue, breathlessness, arthralgia, sleep difficulties, and chest pain. Recent reports also point to the risk of long-term sequela with cutaneous, respiratory, cardiovascular, musculoskeletal, mental health, neurologic, and renal involvement in those who survive the acute phase of the illness. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s15010-021-01666-x.