Physical Function Differences by COVID-19 Status: A Cross-sectional Analysis From the RECOVER Adult Cohort.

Importance: Many adults with prior SARS-CoV-2 infection have persistent limitations, but few studies have examined objective physical function impairment that persist longer than 3 months after infection.

Objective: The objective was to characterize physical function impairment among adults with and without SARS-CoV-2 infection.

Design: This study was a retrospective, cross-sectional analysis.

Setting: Researching COVID to Enhance Recovery (RECOVER) initiative, a multi-site observational study in the United States (ClinicalTrials.gov: NCT05172024).

Participants: Participants were adults ≥18 years old with and without SARS-CoV-2 infection.

Exposures: Groups were defined based on COVID-19 status at enrollment: never diagnosed (control), diagnosed with COVID-19 ≤ 12 weeks (recent COVID-19), or > 12 weeks prior to enrollment (remote COVID-19). The RECOVER-Adult Long COVID Index was used to further characterize by Index ≥12 versus 0.

Main Outcomes/measures: Physical function (main outcome) was assessed by number of repetitions on a 30-second sit-to-stand test (30STS).

Results: 30STS assessments at enrollment were available from 11,578 participants. 30STS repetitions were lowest in the remote COVID-19 group (n = 4942) with 11.5 (SD = 4.2) repetitions compared to 12.5 (SD = 4.7) repetitions among controls (n = 1887) or 12.2 (SD = 4.5) in recent COVID-19 (n = 4698). Remote COVID-19, but not recent COVID-19, was associated with lower physical function in the adjusted model (-0.61 repetitions; SD = 0.21). Those with RECOVER Long COVID Research Index ≥12 performed 1.6 (SD = 0.2) fewer repetitions than those with an Index equal 0.

Conclusions: Physical function impairment did not show clinically meaningful group differences between RECOVER Adult Cohort participants by COVID-19 status, or by Long COVID Index. Individual responses over time or in response to an intervention may be more clinically relevant.

Relevance: In the RECOVER adult cohort, overall physical function differences by time since COVID-19 or by Long COVID Index were small. Individualized assessments are needed to determine functional impairment following COVID-19 diagnosis and subsequent steps for rehabilitation interventions.