2023 HSR&D/QUERI National Conference

4021 — Insights into COVID-19 Vaccine Uptake from Cluster Analysis of Veterans’ Thoughts and Feelings about COVID Infection and Vaccine Safety/Effectiveness

Lead/Presenter: Elijah Lovelace
All Authors: Lovelace EZ (Center for Health Equity Research and Promotion, VA Pittsburgh Healthcare System), Sidani JE (University of Pittsburgh School of Public Health) Pellathy T (Highmark Health; Center for Health Equity Research and Promotion, VA Pittsburgh Healthcare System) Hoffman BL (University of Pittsburgh School of Public Health) Barrett AK (Center for Health Equity Research and Promotion, VA Pittsburgh Healthcare System, VA Center for Medication Safety) Beyer NM (Center for Health Equity Research and Promotion, VA Pittsburgh Healthcare System) Burkitt KH (Center for Health Equity Research and Promotion, VA Pittsburgh Healthcare System) Mor MK (Center for Health Equity Research and Promotion, VA Pittsburgh Healthcare System; University of Pittsburgh School of Public Health) Rodriguez KL (Center for Health Equity Research and Promotion, VA Pittsburgh Healthcare System) Sonel AF (VA Pittsburgh Healthcare System) Switzer G (Division of General Internal Medicine, University of Pittsburgh School of Medicine) Wolynn R (University of Pittsburgh School of Public Health) Fine MJ (Center for Health Equity Research and Promotion, VA Pittsburgh Healthcare System; Division of General Internal Medicine, University of Pittsburgh School of Medicine)

Objectives:
Despite strong evidence supporting the transmissibility and severity of COVID-19 (C-19) infection and the safety and effectiveness of C-19 vaccination, vaccine uptake falls short of national goals, even with Veterans Health Administration (VA) programs that facilitate universal C-19 vaccine access for Veterans. Whereas vaccine hesitancy strongly contributes to suboptimal C-19 vaccine uptake, how unique constellations of Veteran thoughts and feelings influence vaccine uptake remain unknown. Our aims were to determine: (1) what typologies (i.e., clusters) can be derived from C-19-related thoughts and feelings, and (2) whether cluster membership is independently associated with C-19 vaccine uptake.

Methods:
In this partnered Quality Improvement project conducted at the VA Pittsburgh Healthcare System (VAPHS), we developed and administered a 60-item questionnaire reflecting World Health Organization domains (e.g., thoughts and feelings, social factors) associated with C-19 vaccine uptake to a diverse sample of Veterans engaged in primary care at VAPHS. From 32,271 eligible Veterans, we administered a web-based questionnaire or telephone interviews with identical items to all female (n = 1,980) and Hispanic or non-White Veterans (n = 1,708), and randomly selected 500 male, non-Hispanic white Veterans across 4 age categories. We defined vaccination status from participant-reported receipt of 1+ doses of a U.S. Food and Drug Administration-approved C-19 vaccine and used k-means cluster analysis to identify patient typologies from 6 survey items gauging participants’ thoughts and feelings about C-19 infection and vaccine safety/effectiveness. We used multivariable logistic regression to assess the independent association between cluster group membership and vaccination status, adjusting for baseline respondent characteristics and trust in C-19 information sources.

Results:
From our sampling frame of 5,688 Veterans, 1,182 (20.7%) responded; 657 (55.6%) respondents were < age 65, 517 (43.8%) women, 811 (68.6%) non-Hispanic White, 297 (25.1%) African American, and 47 (4.0%) Hispanic. Among 4 distinct clusters identified, the 2 most dissimilar, Vigilant and Encouraged (n = 377) and Skeptical and Indifferent (n = 182), differed in concern about severe illness from C-19 (94.7% vs 14.3%), concern about long-term complications from the vaccine (8.5% vs 75.8%), and perceived vaccine effectiveness in preventing severe illness (98.7% vs 12.6%). Compared to Vigilant and Encouraged, the Carefree and Confident (n = 335) and Guarded yet Optimistic (n = 288) clusters also had high levels of perceived effectiveness of the vaccine (83.9% and 88.9%) but differed in either concerns about C-19 infection or vaccine safety. Overall, 1,014 (85.8%) of respondents were vaccinated, with rates ranging from 31.3% (Skeptical and Indifferent) to 98.9% (Vigilant and Encouraged) by cluster (p < .0001). Compared to Skeptical and Indifferent, adjusted odds ratios for C-19 vaccination by cluster ranged from 12.1 for Carefree and Confident to 45.8 for Vigilant and Encouraged (p < .0001).

Implications:
We identified 4 distinct clusters based on Veterans’ thoughts and feelings about C-19 infection, and vaccine safety/effectiveness. Cluster membership was strongly, independently associated with C-19 vaccination uptake.

Impacts:
VA operations and clinical leaders can use this empirical knowledge to understand how patterns of Veteran C-19 related thoughts and feelings are associated with vaccine hesitancy and tailor interventions to augment C-19 vaccine uptake in identifiable Veteran subgroups with sub-optimal vaccination rates.