Kogevinas, ManolisKarachaliou, MariannaEspinosa Díaz, AnaIraola Guzmán, SusanaCastaño Vinyals, GemmaDelgado Ortiz, LauraFarré, XavierBlay, NataliaPearce, Neil E.Bosch de Basea i Gómez, Magda, 1982-Alonso Nogués, EvaDobaño, CarlotaMoncunill, GemmaCid Ibeas, Rafael deGarcía Aymerich, Judith2025-05-062025-05-062025Kogevinas M, Karachaliou M, Espinosa A, Iraola-Guzmán S, Castaño-Vinyals G, Delgado-Ortiz L, et al. Risk, determinants, and persistence of long-COVID in a population-based cohort study in Catalonia. BMC Med. 2025 Mar 14;23(1):140. DOI: 10.1186/s12916-025-03974-71741-7015http://hdl.handle.net/10230/70301Background: Long-COVID has mostly been investigated in clinical settings. We aimed to assess the risk, subtypes, persistence, and determinants of long-COVID in a prospective population-based study of adults with a history of SARS-CoV-2 infection in Catalonia. Methods: We examined 2764 infected individuals from a population-based cohort (COVICAT) established before the pandemic and followed up three times across the pandemic (2020, 2021, 2023). We assessed immunoglobulin (Ig)G levels against SARS-CoV-2, clinical, vaccination, sociodemographic, and lifestyle factors. Long-COVID risk and subtypes were defined based on participant-reported symptoms and electronic health records. We identified a total of 647 long-COVID cases and compared them with 2117 infected individuals without the condition. Results: Between 2021 and 2023, 23% of infected subjects developed long-COVID symptoms. In 56% of long-COVID cases in 2021, symptoms persisted for 2 years. Long-COVID presented clinically in three subtypes, mild neuromuscular, mild respiratory, and severe multi-organ. The latter was associated with persistent long-COVID. Risk was higher among females, participants under 50 years, of low socioeconomic status, severe COVID-19 infection, elevated pre-vaccination IgG levels, obesity, and prior chronic disease, particularly asthma/chronic obstructive pulmonary disease and mental health conditions. A lower risk was associated to pre-infection vaccination, infection after omicron became the dominant variant, higher physical activity levels, and sleeping 6-8 h. Vaccination during the 3 months post-infection was also protective against long-COVID. Conclusions: Long-COVID persisted for up to 2 years in half of the cases, and risk was influenced by multiple factors.application/pdfeng© The Author(s) 2025. Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.info:eu-repo/semantics/articlehttp://dx.doi.org/10.1186/s12916-025-03974-7COVID-19EpidemiologyExerciseLong-COVIDSARS-CoV-2 antibodiesSleepVaccinesinfo:eu-repo/semantics/openAccess