Physical, cognitive, and social triggers of symptom fluctuations in people living with long COVID: an intensive longitudinal cohort study
Darren C. Greenwood, Maedeh Mansoubi, Nawar Diar Bakerly, Aishwarya Bhatia, Johnny Collett, Helen Davies, Jo Dawes, Brendan Delaney, Leisle Ezekiel, Phaedra Leveridge, Ghazala Mir, Willie Muhlhausen, Clare Rayner, Flo Read, J. T. Scott, Manoj Sivan, Ian Tucker-Bell, Himanshu Vashisht, Tomás Ward, Daryl B. O’Connor, Helen Dawes, Helen Dawes, Nawar D. Bakerly, Kumaran Balasundaram, Megan Ball, Mauricio Barahona, Alexander Casson, Jonathan Clarke, Karen Cook, Rowena Cooper, Vasa Curcin, Julie Darbyshire, Helen E. Davies, Helen Dawes, Simon de Lusignan, Brendan Delaney, Carlos Echevarria, Sarah Elkin, Ana Belen Espinosa Gonzalez, Rachael Evans, Sophie Evans, Zacchaeus Falope, Ben Glampson, Madeline Goodwin, Trish Greenhalgh, Darren C. Greenwood, Darren C. Greenwood, Stephen Halpin, Juliet Harris, Will Hinton, Mike Horton, Samantha Jones, Joseph Kwon, Cassie Lee, Ashliegh Lovett, Mae Mansoubi, Victoria Masey, Harsha Master, Erik Mayer, Bernardo Meza-Torres, Ruairidh Milne, Ghazala Mir, Jacqui Morris, Adam Mosley, Jordan Mullard, Daryl O'Connor, Rory O'Connor, Thomas Osborne, Amy Parkin, Stavros Petrou, Anton Pick, Denys Prociuk, Clare Rayner, Amy Rebane, Natalie Rogers, Janet T. Scott, Manoj Sivan, Adam B. Smith, Nikki Smith, Emma Tucker, Ian Tucker-Bell, Paul Williams, Darren Winch, Conor Wood
Abstract
Background: Symptom fluctuations within and between individuals with long COVID are widely reported, but the extent to which severity varies following different types of activity and levels of exertion, and the timing of symptoms and recovery, have not previously been quantified. We aimed to characterise timing, severity, and nature of symptom fluctuations in response to effortful physical, social and cognitive activities, using Ecological Momentary Assessments. Methods: We recorded activity, effort, and severity of 8 core symptoms every 3 h for up to 24 days, in cohorts from both clinic and community settings. Symptom severities were jointly modelled using autoregressive and moving average processes. Findings: Consent was received from 376 participants providing ≥1 week's measurements (273 clinic-based, 103 community-based). Severity of all symptoms was elevated 30 min after all categories of activity. Increased effort was associated with increased symptom severity. Fatigue severity scores increased by 1.8/10 (95% CI: 1.6-1.9) following the highest physical exertions and by 1.5 (1.4-1.7) following cognitive efforts. There was evidence of only mild delayed fatigue 3 h (0.3, 0.2-0.5) or one day later (0.2, 0.0- 0.5). Fatigue severity increased as the day progressed (1.4, 1.0-1.7), and cognitive dysfunction was 0.2 lower at weekends (0.1-0.3). Interpretation: Cognitive, social, self-care and physical activities all triggered increased severity across every symptom, consistent with associated common pathways as potential therapeutic targets. Clear patterns of symptom fluctuations emerged that support more targeted self-management. Funding: National Institute for Health and Care Research.