Identifying social determinants of health subgroups and their associations with health outcomes in a prospective US adult COVID-19 cohort: an analysis of the INSPIRE registry.

Latent class analysis identified four distinct SDOH subgroups among COVID-19 patients with significant demographic differences across classes.

• A 4-class model was identified as optimal based on lowest Bayesian Information Criterion (BIC=42,150.9) after evaluating 1-7 class models
• Significant demographic differences were confirmed across classes (χ² p<0.001 for gender, age, race, ethnicity, education and income distributions)
• Class 1: lower-income, predominantly Hispanic young to middle-aged adults (n=499, 13.2%); Class 2: lower-income, older, predominantly Black non-Hispanic (n=1828, 48.2%); Class 3: middle-aged, high-income non-Hispanic (n=599, 15.8%); Class 4: young to middle-aged, highly educated, high-income non-Hispanic (n=865, 22.8%)
• Sensitivity analysis using four age groups yielded higher BIC (45,430.8) than the three age group primary model (BIC=42,150.9), confirming the primary model

Class 1 (lower-income, predominantly Hispanic young to middle-aged adults) exhibited significantly worse anxiety and cognitive function compared to the reference group at both 3 and 6 months post-infection.

• Class 1 showed significantly worse 3-month anxiety compared to the reference Class 3 (β=4.41, 95% CI 3.25 to 5.56, p<0.001)
• Class 1 showed significantly worse 3-month cognitive function (β=-3.29, 95% CI -4.77 to -1.82, p<0.001)
• Worse outcomes were observed across physical and mental health domains at both 3-month and 6-month follow-ups
• Reference group (Class 3) was middle-aged, high-income non-Hispanic adults (n=599)

Class 2 (lower-income, older, predominantly Black non-Hispanic adults) showed significantly worse depression, cognitive function, and higher odds of missed workdays compared to the reference group.

• Class 2 showed significantly worse 3-month depression compared to the reference Class 3 (β=3.58, 95% CI 2.53 to 4.64, p<0.001)
• Class 2 had significantly higher odds of missed workdays (>1 week) at 6 months (OR=1.853, 95% CI 1.192 to 2.880, p=0.006)
• Class 2 exhibited significantly worse cognitive function at both 3-month and 6-month time points
• Class 2 was the largest subgroup, comprising 48.2% of the study sample (n=1828)

Class 4 (young to middle-aged, highly educated, high-income non-Hispanic adults) consistently reported the most favorable health outcomes post-COVID-19 infection.

• Class 4 reported better physical function at 3 months compared to the reference group (β=2.04, p<0.001)
• Class 4 reported lower pain interference compared to the reference group
• Class 4 comprised 22.8% of the study sample (n=865)
• Class 4 showed consistently favorable outcomes across physical and mental health domains at both follow-up time points

The INSPIRE registry enrolled 3791 eligible participants with the majority being young to middle-aged, female, white, and non-Hispanic.

• Of 3791 eligible participants with complete baseline data, 2897 (76.4%) completed the 3-month follow-up and 2666 (70.3%) completed the 6-month follow-up
• Most participants were aged 18-49 years (74-75%), female (66-67%), white (86.6-87.5%), and non-Hispanic (86.6-87.5%)
• Participants were enrolled from 9 December 2020 to 12 August 2022 across eight US academic medical centres
• Eligible participants were adults ≥18 years, fluent in English or Spanish, with confirmed positive SARS-CoV-2 test within 42 days before enrolment

Health outcome disparities between SDOH subgroups persisted at both 3-month and 6-month follow-up time points post-SARS-CoV-2 infection.

• Primary outcomes included PROMIS-29 V.2.1 T-scores for depression, anxiety, fatigue, sleep disturbance, pain interference, physical function, and social participation
• Cognitive function was measured using PROMIS Cognitive Function Short Form 8 T-scores
• Missed workdays were assessed as a binary outcome (>1 week vs ≤1 week) via single-item survey
• All measures were self-reported and collected at baseline, 3 months, and 6 months
• Classes 1 and 2 exhibited significantly worse outcomes across multiple physical and mental health domains at both time points compared to the reference group