Gaps in Long COVID treatments research: A scoping review

Background Long COVID affects 6 to 10% of people following SARS-CoV-2 infection. It has been documented worldwide, with over 200 symptoms reported. This scoping review assesses the evidence on Long COVID treatments to identify gaps in the evidence-base to inform research prioritisation. Methods We searched four databases (MEDLINE, Embase, Cochrane’s Trial register, Epistemonikos) supplemented by a grey literature search up to April 2023. Two reviewers screened articles and extracted data. Data were analysed using a thematic approach. Results Of 3675 records identified, 26 studies were included. Most were in high-income countries (92%), with two in upper-middle-income countries (8%). None reported inclusion of children, nor pregnant women and only 37.5% included adults over 64 years. Five (20.8%) presented ethnicity data, of these 92.9% of participants were of white ethnicity. Treatments included nutritional supplements (46%), conventional medicines (38%), hyperbaric medicine (8%), COVID-19 vaccination (4%) and complementary, alternative medicine (4%). Conclusion This scoping review highlights that more than four years after the start of the pandemic, research gaps remain for Long COVID treatments. There is a lack of research in low-income countries, despite trials being best placed locally to reflect different population demographics. There is a lack of inclusion of population sub-groups, particularly children, pregnant women and ethnic minority groups. Inclusion of these groups in future research is important given they may be at a higher risk of adverse outcomes of COVID-19, and a lack of appropriate treatments for Long COVID may contribute to the widening of health inequalities.