Severe COVID-19 is associated with sustained biochemical disturbances and prolonged symptomatology; A retrospective single-centre cohort study

Abstract

Introduction: Coronavirus disease 2019 (COVID-19) is associated with significant acute clinical manifestations, and reports indicate that some patients experience prolonged symptomatology and morbidity. These late clinical manifestations have been termed Post-Acute Sequelae of COVID-19 (PASC) and hypothesised to be associated with clinical severity in the acute infection phase and biochemical abnormalities. Aim: Evaluate the incidence of PASC in previously hospitalised COVID-19 patients and compare the admission and follow-up levels of biochemical parameters stratified according to baseline clinical severity. Methods: N = 168 COVID-19 patients previously hospitalised at the Zan Mitrev Clinic in Skopje, North Macedonia, with matched laboratory data at baseline and follow-up clinical visit > 30 days post-discharge, were stratified according to National Institute of Health clinical severity guidelines as mild, moderate, severe or critical according to admission clinical presentation. We assessed the incidence of PASC and compared the biochemical profile. Results: The median hospitalisation and clinical follow-up period were 11 (9-20) and 53 (30-105) days. The overall incidence of PASC was 56.5% (95/168); most PASC cases were confined to the severe sub-group (61/101, 61.4%). Contrary to mild and moderate cases and a healthy non-COVID-19 control cohort, we observed that severe COVID-19 cases experienced sustained biochemical disturbances, most notably elevated D-dimers and Ferritin of 600 ng/ml (283-1168) and 432 ng/ml (170-916), respectively. Conclusions: Previously hospitalised severe COVID-19 patients are more likely to experience Post-Acute Sequelae of COVID-19 and prolonged biochemical disturbances, evident by abnormal values of D-dimers and Ferritin.