Prevalence and predictors of long COVID among non-hospitalised adolescents and young adults: a prospective controlled cohort study

Abstract

The prevalence and predictors of long COVID in young people remain unresolved. We aimed to determine the point prevalence of long COVID in non-hospitalised adolescents and young adults six months after the acute infection, to determine the risk of developing long COVID adjusted for possible confounders, and to explore a broad range of potential risk factors (prespecified outcomes). We conducted a prospective controlled cohort study of 404 SARS-CoV-2-positive and 105 SARS-CoV-2-negative non-hospitalised individuals aged 12–25 years (ClinicalTrial ID: NCT04686734). Data acquisition was completed February 2022. Assessments included pulmonary, cardiac and cognitive functional testing, biomarker analyses, and completion of a questionnaire, and were performed at inclusion (early convalescent stage) and six months follow-up. The WHO case definition of long COVID was applied. The point prevalence of long COVID at six months was 49% and 47% in the SARS-CoV-2-positive and negative group, respectively. SARS-CoV-2-positivity did not predict development of long COVID (relative risk 1.06, 95% CI 0.83 to 1.37). The main predictor was symptom severity at inclusion, which correlated strongly to personality traits. Low physical activity and loneliness were also predictive, while biological markers were not. In conlusion, our study aims were met, and the findings suggest that persistent symptoms were not driven by the infection, but were associated with psychosocial factors.

The long-term impacts of COVID-19 on confirmed cases at least 12 months post-infection in Wellington, New Zealand: an observational, cross-sectional study

“…24 In another cohort study of non-hospitalised participants, there was no difference in blood test results between COVID-19 patients and controls at a 6 months follow up. 25 Comparison of our study with other studies of long COVID is challenging given the variety of methods used, the heterogeneity in questionnaires, differences in patient populations and infected variants, description of symptoms, and disparities in follow-up lengths. Since infection with alpha and beta variants in our study population, bigger waves of transmission with Delta and Omicron variants have occurred in Aotearoa New Zealand, with evidence pointing to a possibly lower risk of long COVID with the Omicron variant compared to the Delta variant.…”