Characterising Long COVID in an Irish cohort: a study of symptom type, severity and determinants

Abstract Long COVID (LC) is a multisystem disorder impacting 65 million people globally. This secondary analysis of data from the Follow-up After Disease Acquisition (FADA) retrospective cohort study of COVID-19 recovery, aimed to characterise the nature and severity of LC in an Irish sample. The Modified COVID-19 Yorkshire Rehabilitation Scale categorised symptoms. Data analysis employed descriptive statistics and logistic regression. Of 4,671 respondents, 2,338 (50.1%) self-reported LC. LC participants were predominantly female (1,543, 66%), White Irish (1,512, 84.9%), and highly-educated (1,174, 65.8%). 907 (51.5%), had ≥one baseline co-morbidity. Most (1,076, 59.1%) had never smoked. Only 6.9% (162) of LC cases were ever hospitalised with acute COVID-19. Recovery was reported by 979 (41.9%). Of those with persistent symptoms 306 (31.6%) were classified as “moderate/severe.” Fatigue was predominant, (1,021, 75.1%) accompanied by cognitive dysfunction (932, 68.5%) and breathlessness (870, 64.0%). Functional impairment, assessed by the EQ-5D-5L score, was evident. Factors associated with LC persistence and severity included baseline co-morbidities (aOR persistent LC 1.44 [95% CI 1.12-1.85], p = 0.005; aOR moderate/severe LC 2.90 [1.92-4.37] p < 0.001)), smoking (aOR persistent LC 1.59 [1.11-2.28] p = 0.01, aOR moderate/severe=1.65 [1.0-2.71] p = 0.05), and meeting/exceeding WHO’s physical activity guidelines (aOR persistent LC 1.49 [1.16-1.92], p = 0.002, aOR moderate/severe=1.69 [1.12-2.54], p = 0.01). LC’s diverse symptomatology and functional impairment serve as a call to action to the health service to equip itself to address this complexity. This study offers insights into LC symptom type, duration, and determinants, emphasising the need for Public Health to traverse domains, to improve all facets of population health. These findings add to the current understanding of LC, providing a foundation for the development of tailored LC services. Key messages • Long COVID causes a constellation of diverse symptoms. • The Irish Health service needs to be equipped to manage the diverse symptomatologu.