New Symptom-Based Long COVID Definition Provides Investigation Framework

by Linda Kossoff •

What is a workable definition of the term “postacute sequelae of SARS-CoV-2 (PASC),” and what are PASC frequencies across cohorts, vaccination status, and number of infections?

BOTTOM LINE

A symptom-based PASC definition was developed that serves as a launching point for further investigations.

BACKGROUND: PASC short- and long-term effects have substantial impacts on health-related quality of life, earnings, and healthcare costs. Defining PASC precisely is difficult because it is heterogeneous. Most PASC studies have generated widely divergent estimates of prevalence.

STUDY DESIGN: Prospective cohort study.

SETTING: Massachusetts General Hospital, Boston, Mass.

SYNOPSIS: Researchers analyzed data from 9,764 participants enrolled in RECOVER, an ongoing study of adults with and without SARS-CoV-2 infection at 85 enrolled sites. Participants belonged to either the acute or postacute cohort (enrolled <30 days since or >30 days to three years after first positive test result/symptom onset, respectively). Subjects enrolled before April 10, 2023, completed a symptom survey >six months of test date/acute symptom onset. Within the group, 89% were SARS-CoV-2 infected, 71% were female, 16% were Hispanic/Latino, and 15% were non-Hispanic Black. Adjusted odds ratios were 1.5 or greater (infected vs. uninfected) for 37 symptoms across multiple pathophysiological domains, including post-exertional malaise, fatigue, brain fog, dizziness, gastrointestinal symptoms, and loss of/change in smell or taste. A preliminary rule for identifying PASC was derived based on a composite symptom score. Considering previously reported assessments of PASC manifestations with these multiple self-reported symptoms enabled researchers to develop a scoring algorithm that provides a framework for diagnosing PASC. Study limitations included anticipated evolution and refinement of phenotypes.

CITATION: Thaweethai T, Jolley SE, Karlson EW, et al. Development of a definition of postacute sequelae of SARS-CoV-2 infection. JAMA. 2023;329:1934–1946.