Is Long COVID associated with an increased risk of mortality?

Contract Description

Long COVID (post-acute sequelae of COVID-19) has been associated with a variety of clinical manifestations that may produce lasting morbidity, but the impact of Long COVID on mortality risk remains unclear. A recent descriptive study of death certificate data in the US National Vital Statistics System ( has disclosed cases in which long COVID terms appeared in death certificates, indicating Long COVID as an underlying or contributing cause of death. The fundamental question being asked is: Is Long COVID associated with an increased risk of mortality relative to patients who experience acute COVID-19 not followed by Long COVID, and a population of uninfected individuals.

Contract Aims

Leveraging data in the N3C enclave, assess (1) the impact of Long COVID on the risk of all-cause mortality at one year, (2) the demographic and clinical characteristics and risk factors associated with mortality among patients with Long COVID. Quantitatively characterize these risks, accounting for relevant covariates, using retrospective data in the enclave.

Analysis Plan / Research Method

Be explicit about how your study design, research methodology, and analytical plan will address the overall research question and aims. See the detailed guidance on expectations at the submission portal when completing the relevant fields in your proposal.

Expected Results

See Deliverables

Inclusion Criteria

Be explicit about how your inclusion strategy will rigorously address the overall question and aims.

Exclusion Criteria

Be explicit about how your exclusion strategy will rigorously address the overall question and aims.


See inclusion and exclusion sections. Also address the fact that the ICD-10 U09.9 diagnosis code for Long COVID in the electronic health record may underestimate the true incidence of Long COVID.


Written report within the N3C Enclave detailing the findings from analyses that support your conclusions and that address the overall research questions and aims. Provide sufficient methodologic detail for independent replication of the work, and an interpretation of the findings and study limitations. All code generated to complete the work will be made available in a deployable format with sufficient documentation/annotation for independent validation. Figures and/or tables in a format specified by NCATS suitable for uploading to the N3C Public Health web site.

Application Open Date
Jan 23, 2023
Application Close Date
Feb 15, 2023
Number of Contracts
Contract Amount
Length of Contract
2 months
PHASTR Public Health Contact