The association between physical distancing behaviors to avoid COVID-19 and health-related quality of life in immunocompromised and nonimmunocompromised individuals: patient-informed protocol for the observational, cross-sectional EAGLE study

Background:

Immunocompromised individuals are known to respond inadequately to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines, placing them at high risk of severe or fatal coronavirus disease 2019 (COVID-19). Thus, immunocompromised individuals and their caregivers may still practice varying degrees of social/physical distancing to avoid COVID-19. However, the association between physical distancing to avoid COVID-19 and quality of life has not been comprehensively evaluated in any study.

Objective:

We aim to measure physical distancing behaviors among immunocompromised individuals and the association of those behaviors with person-centric outcomes, including health-related quality of life (HRQoL) measures, health state utilities, anxiety and depression, and work and school productivity impairment.

Methods:

A patient-informed protocol was developed to conduct the EAGLE Study, a large cross-sectional, observational study, and this article describes that protocol. EAGLE is designed to measure distancing behaviors and outcomes in immunocompromised individuals, including children (age ≥6 months) and their caregivers, and non-immunocompromised adults in the United States and United Kingdom who report no receipt of passive immunization against COVID-19. We previously developed a novel self- and observer-reported instrument, the Physical Distancing Scale for COVID-19 Avoidance (PDS-C19), to measure physical distancing behavior levels cross-sectionally and retrospectively. Using an interim or a randomly selected subset of the study population, PDS-C19 psychometric properties will be assessed, including structural validity, internal consistency, known-groups validity, and convergent validity. Associations (correlations) will be assessed between PDS-C19 and validated HRQoL-related measures and utilities. Structural equation modeling and regression will be used to assess these associations, adjusting for potential confounders. Participant recruitment and data collection occurred from December 2022 to June 2023, using direct-to-patient channels including panels, clinician referral, patient advocacy groups, and social media, with immunocompromising diagnosis confirmation collected and assessed for a randomly selected 25% of immunocompromised participants. Planned total sample size is 3718 participants/participant-caregiver pairs. Results will be reported by immunocompromised status, immunocompromising condition category, country, age group, and other subgroups.

Results:

All data analyses and reporting are to be completed by December 2023.

Conclusions:

This study will quantify immunocompromised individuals’ physical distancing behaviors to avoid COVID-19 and their association with HRQoL, as well as health state utilities.