Incidence, Associated Factors, and Burden of Post COVID-19 Condition in Brazil

Study Overview
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Brief Summary
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This is a national retrospective cohort study with internet-based recruitment which intends to enroll 1,694 adult patients with COVID-19 diagnosis during the SARS-CoV-2 omicron wave in Brazil. Participants with confirmed symptomatic COVID-19 after january 2022 will be evaluated in order to assess incidence, potential risk factors and impact of post COVID-19 condition according to the WHO definition on health-related quality of life and other relevant patient-centered outcomes.

Official Title
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Incidence, Associated Factors, and Burden of Post COVID-19 Condition in Brazil

Conditions
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Post-Acute COVID-19 Syndrome

Intervention / Treatment
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* Other: Multiple exposures


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 18 years; Brazilian resident; Symptomatica COVID-19 confirmed by reverse transcriptase polymerase chain reaction (RT-PCR) or antigen test for SARS-COV-2 after January 2022, with diagnosis at least 90 days before recruitment. Exclusion Criteria: No availability to participate in remote research appointments; Communication difficulty (aphasia, important hearing loss, non-portuguese speaker, severe dementia) Refuse to provide informed consent

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Individuals with COVID-19 diagnosis during the SARS-CoV-2 omicron wave in Brazil<br> | Other: Multiple exposures<br>* Exposures variables (observational study): age, gender, education, comorbidities, vaccination status, severity of the acute episode of COVID-19, treatments used for acute COVID-19.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Post COVID-19 condition according to the WHO definition | Post COVID-19 condition occurs in individuals with a history of probable or confirmed SARS CoV-2 infection, usually 3 months from the onset of COVID-19 with symptoms and that last for at least 2 months and cannot be explained by an alternative diagnosis | 3 to 24 months | 
| EQ5D-3L | Health-related quality of life assessed using the EuroQol five-dimensional 3-level descriptive system (EQ5D-3L). This outcome will be considered as primary when Post COVID-19 condition be used as exposure. | 3 to 24 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Instrumental activities of daily living | Instrumental activities of daily living assessed with the Lawton & Brody Instrumental Activities of Daily Living | 3 to 24 months | 
| Functional status | Functional status assessed with the Modified Barthel Index | 3 to 24 months | 
| Cognition | Cognition assessed with the Telephone Interview for Cognitive Status | 3 to 24 months | 
| Anxiety symptoms | Anxiety symptoms assessed with the Hospital Anxiety and Depression Scale; | 3 to 24 months | 
| Depression symptoms | Depression symptoms assessed with the Hospital Anxiety and Depression Scale; | 3 to 24 months | 
| Posttraumatic stress symptoms | Posttraumatic stress symptoms assessed with the Impact Event Scale-Revised | 3 to 24 months | 
| Time to return to work or studies | Time to return to work or studies after COVID-19 | 3 to 24 months | 
| Healthcare utilization | Medical and rehabilitation appointments, medication use and diagnostic tests | 3 to 24 months | 
| Costs | Individual health-related and COVID-19-related costs | 3 to 24 months |