PREPRINT: Multi-organ impairment and Long COVID: a 1-year prospective, longitudinal cohort study

Multi-organ impairment associated with Long COVID is a significant burden to individuals, populations and health systems, presenting challenges for diagnosis and care provision. Standardised assessment across multiple organs over time is lacking, particularly in non-hospitalised individuals.

Objective To determine the prevalence of organ impairment in Long COVID patients at 6 and at 12 months after initial symptoms and to explore links to clinical presentation.

Design This was a prospective, longitudinal study in individuals following recovery from acute COVID-19. We assessed symptoms, health status, and multi-organ tissue characterisation and function, using consensus definitions for single and multi-organ impairment. Physiological and biochemical investigations were performed at baseline on all individuals and those with organ impairment were reassessed, including multi-organ MRI, 6 months later.

Setting Two non-acute settings (Oxford and London).

Participants 536 individuals (mean 45 years, 73% female, 89% white, 32% healthcare workers, 13% acute COVID-19 hospitalisation) completed baseline assessment (median: 6 months post-COVID-19). 331 (62%) with organ impairment or incidental findings had follow up, with reduced symptom burden from baseline (median number of symptoms: 10 and 3, at 6 and 12 months).

Exposure SARS-CoV-2 infection 6 months prior to first assessment.

Main outcome Prevalence of single and multi-organ impairment at 6 and 12 months post-COVID-19.

Results Extreme breathlessness (36% and 30%), cognitive dysfunction (50% and 38%) and poor health-related quality of life (EQ-5D-5L<0.7; 55% and 45%) were common at 6 and 12 months, and associated with female gender, younger age and single organ impairment. At baseline, there was fibro-inflammation in the heart (9%), pancreas (9%), kidney (15%) and liver (11%); increased volume in liver (7%), spleen (8%) and kidney (9%); decreased capacity in lungs (2%); and excessive fat deposition in the liver (25%) and pancreas (15%). Single and multi-organ impairment were present in 59% and 23% at baseline, persisting in 59% and 27% at follow-up.

Conclusion and Relevance Organ impairment was present in 59% of individuals at 6 months post-COVID-19, persisting in 59% of those followed up at 1 year, with implications for symptoms, quality of life and longer-term health, signalling need for prevention and integrated care of Long COVID.

Trial Registration Identifier: NCT04369807

Key points

Question: What is the prevalence of organ impairment in Long COVID at 6- and 12-months post-COVID-19?

Findings: In a prospective study of 536 mainly non-hospitalised individuals, symptom burden decreased, but single organ impairment persisted in 59% at 12 months post-COVID-19.

Meaning: Organ impairment in Long COVID has implications for symptoms, quality of life and longer-term health, signalling need for prevention and integrated care of Long COVID.

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