ABSTRACT

Objectives Post Acute Sequele of COVID-19 (PASC) is a remaining health concern after the pandemic. We aimed to investigate the prevalence of diagnoses and symptom diagnoses recorded before and during the pandemic in individuals who later received PASC.

Methods A case-control study was designed to investigate the prevalence of registered diagnoses in adult, non-hospitalized PASC patients (cases) 2019, 12 months before and 6 months after the PASC diagnosis compared to matched controls. Data was extracted from the Stockholm Region’s data warehouse (VAL).

Results Results indicate higher diagnosis rates for men and women with PASC already in 2019 and 12 months before diagnosis; slightly decreasing 6 months after PASC. Cases showed more pre-pandemic respiratory diagnoses compared to controls. In 2019, cases had higher rates of acute upper respiratory tract infection (OR 2.47 for men, 2.22 for women), asthma (OR 1.76 (men), 1.95 (women)), and bronchitis (OR 2.15 (men), 2.71 (women)) than controls.

Conclusions The present study showed that individuals who later developed PASC were more likely than others to show respiratory symptoms before COVID-19. Pre-existing vulnerabilities observed before the pandemic in those later diagnosed with PASC in 2021 suggest a potential link between prior conditions and PASC development.

Competing Interest Statement

The authors have declared no competing interest.

Funding Statement

This study was funded by Region Stockholm FoUI-97300, Swedish Heart-lung foundation, and Swedish Research Council.

Author Declarations

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Swedish Ethical Review Authority gave Ethical approval for this work.

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Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

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I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

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Data Availability

All data produced in the present work are contained in the manuscript

List of abbreviationsPASCPost Acute Sequelae of COVID-19VALStockholm Regional Health Care Data WarehouseICD-10International Classification of Diseases, 10th editionORodds ratioCIconfidence interval.