Resources

Public Health Ontario (PHO) is actively monitoring, reviewing and assessing relevant information related to Coronavirus Disease 2019 (COVID-19), caused by severe acute respiratory coronavirus 2 (SARS-CoV-2). This rapid review concentrates on results from systematic reviews and meta-analyses, updating the evidence on the prevalence of PACS, PACS symptoms by organ system and risk factors for developing PACS. The update includes more meta-analyses and primary research with larger sample sizes and includes a new section reporting on the impacts of PACS on daily living. This rapid review replaces Persistent Symptoms and Post-Acute COVID-19 in Adults – What We Know So Far (April 9, 2021).

Key Messages

• The definition of and diagnostic criteria for post-acute COVID-19 syndrome (PACS) are not yet well established. This rapid review considered PACS as persistent or new sequelae present 3 or more weeks after severe, mildly symptomatic or asymptomatic SARS-CoV-2 infection.
• Pooled mean prevalence results for any experience of PACS, extracted from nine systematic reviews, ranged from 51%–80%.
• Pooled mean prevalence results for specific PACS symptoms were extracted, when available, from 32 systematic reviews. Symptoms and prevalence results varied widely across reviews, however some of the most commonly reported symptoms included fatigue; shortness of breath; anxiety; depression; sleep disorder; cognitive and memory impairments; and negative impacts on quality of life (QoL). The most commonly reported risk factors for developing PACS were increased disease severity during acute SARS-CoV-2 infection and female sex.
• Few included studies used control groups of individuals not infected with SARS-CoV-2 (e.g., healthy controls, patients with alternative diagnoses). These studies consistently found overall greater rates or risk of persistent symptoms consistent with PACS among patients with COVID-19 compared to symptoms in those without COVID-19. Further case-control studies would help disentangle the impact of public health measures, other confounders and SARS-CoV-2 infection on symptoms consistent with PACS.
• Results across reviews and studies with multiple follow up periods did not consistently indicate if prevalence of PACS or PACS sequelae increased, decreased or remained stable over time.
• Overall, while ongoing research is needed to better characterize PACS characteristics and prevalence, this body of evidence indicates PACS is a condition experienced by a substantial number of individuals with previous SARS-CoV-2 infection. Care for patients with PACS will likely place added stresses on health care and social support systems, including increased emergency department visits, outpatient care, inpatient care and rehabilitation involving multidisciplinary teams. 

To read the full review document, please click the linked file.