Risk, determinants, and persistence of long-COVID in a population-based cohort study in Catalonia
Manolis Kogevinas, Marianna Karachaliou, Ana Espinosa, Susana Iraola‐Guzmán, Gemma Castaño‐Vinyals, Laura Delgado‐Ortiz, Xavier Farré, Natàlia Blay, Neil Pearce, Magda Bosch de Basea, Eva Alonso Nogués, Carlota Dobaño, Gemma Moncunill, Rafael de Cid, Judith García‐Aymerich
Abstract
BACKGROUND: 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.