Post-covid-19 conditions in adults: systematic review and meta-analysis of health outcomes in controlled studies

BMJ Med. 2024 Jan 29;3(1):e000723. doi: 10.1136/bmjmed-2023-000723. eCollection 2024.

Abstract

Objective: To assess the impact of post-covid-19 conditions among adults.

Design: Systematic review and meta-analysis of health outcomes in controlled studies.

Data sources: Two sources were searched from database inception to 20 October 2022: Cochrane covid-19 study register (comprising Cochrane Central Register of Controlled Trials, Medline, Embase, clinicalTrials.gov, World Health Organization's International Clinical Trials Registry Platform, medRxiv) and WHO's covid-19 research database.

Eligibility criteria: Cohort studies recruiting more than 100 participants with a control group and a follow-up of at least 12 weeks were included. Adults who were documented to have SARS-CoV-2 infection based on clinical, imaging, or laboratory criteria were included.

Data extraction and synthesis: Two independent reviewers extracted data. The main outcomes included quality of life, functionality in daily activities, use of resources, recovery rates (cluster of symptoms), and the incidence of new medical diagnoses. Data were pooled using a random effects model. The risk of bias was assessed with the Joanna Briggs Institute critical appraisal tool for cohort studies.

Results: We included 63 controlled cohort studies, encompassing more than 96 million participants. Based on five studies, we found a reduction in overall quality of life between individuals with confirmed SARS-CoV-2 infection versus controls at six to 24 months follow-up, although heterogeneity was very high (mean difference in EQ-5D scale -5.28 (95% confidence interval -7.88 to 2.68; I2=93.81%). Evidence from ten studies, which could not be pooled in a meta-analysis, indicated that an increased rate of functional impairment associated with SARS-CoV-2 infection. Use of care increased compared with controls at six to 24 months follow-up at intensive care units (risk ratio 2.00 (95% confidence interval 0.69 to 5.80), five studies, I2=91.96%) and in outpatient care (1.12 (1.01 to 1.24), seven studies, I2=99.51%). Regarding persistent symptoms, individuals with documented SARS-CoV-2 infection had an increased risk of having two or more persistent symptoms at follow-up, especially those related to neurological clusters (ie, risk ratio 1.51 (95% confidence interval 1.17 to 1.93), I2=98.91%). Evidence also showed an increased incidence of a wide variety of metabolic, cardiovascular, neurological, respiratory, haematological and other incident diagnoses.

Conclusion: Evidence suggests functional impairment after SARS-CoV-2 infection, in addition to a higher use of resources and a higher incidence of widely varying medical diagnoses. These results should be interpreted with caution, considering the high heterogeneity across studies and study limitations related to outcome measurement and attrition of participants.

Systematic review registration: Open Science Framework, osf.io/drm39.

Keywords: Epidemiology; Infectious disease medicine; covid-19.