Public Attitudes About Preventive Dementia Vaccine Among US Adults

Abstract

This survey study assesses the willingness of US adults aged 50 years or older to receive a low-cost, multidose vaccine to prevent dementia and stratifies this willingness by respondent age, sex, and race and ethnicity.

Introduction

Dementia is a leading cause of disability and mortality worldwide and imposes a substantial and growing economic burden.^1,2 Efforts to address this burden are increasingly focused on prevention, including interventions before symptom onset. Several preventive strategies are under development, including immunotherapies and vaccine-based approaches that delay or reduce the risk of Alzheimer disease.^3,4 Recent studies linking shingles vaccination to lower dementia risk have increased public and scientific interest in vaccine-based dementia prevention.^5,6 The success of these strategies will depend not only on clinical effectiveness but also on population-level acceptance. However, little is known about how individuals perceive preventive dementia vaccines or whether willingness to adopt varies across sociodemographic groups.

In this study, we used survey data to examine US public attitudes toward a preventive dementia vaccine. Our objective was to ascertain whether willingness to receive this vaccine differed by age, sex, and race and ethnicity.

Methods

We analyzed the 2025 Dementia and Medication survey data from the Understanding America Study, a nationally representative internet panel of US adults (eTable in Supplement 1).⁷ We recruited Hispanic, non-Hispanic Black (hereafter Black), and non-Hispanic White (hereafter White) respondents aged 50 years or older (eMethods in Supplement 1 provides additional details). Participants provided electronic informed consent. The University of Southern California Institutional Review Board approved this survey study. We followed the AAPOR reporting guideline.

Respondents were asked about their willingness to receive a low-cost, multidose vaccine that would reduce dementia risk by 50%, assuming a high risk of future dementia. Response options were on a 7-point scale: definitely no, very unlikely, unlikely, not sure/neutral, likely, very likely, or definitely yes (eFigure in Supplement 1). The multidose formulation reflects the design of vaccine candidates under investigation in dementia prevention trials.^3,4 Differences in willingness to adopt were assessed using ordered logistic regression models, adjusted for demographic and socioeconomic characteristics. Survey weights were applied to produce nationally representative estimates.

Two-sided P < .05 indicated statistical significance. Data analysis was performed using R 4.5.1 (R Project for Statistical Computing).

Results

Among 1529 respondents, the weighted sample had a mean (SD) age of 65.6 (9.3) years and was 52.5% female. Additionally, 45.7% of respondents had a college degree or higher and 11.7% self-identified as Black, 14.6% as Hispanic, and 73.7% as White.

Overall, 72.1% of respondents reported willingness to adopt (likely, very likely, definitely yes), 20.8% reported hesitation (not sure/neutral), and 7.2% reported no willingness (definitely no, very unlikely, unlikely). Patterns varied systematically across sociodemographic groups. Willingness to adopt increased with age, with definitely-yes responses increasing from 31.1% among respondents aged 50 to 59 years to 35.1% among those 70 years or older. Hesitation was highest at 26.0% among respondents aged 50 to 59 years. Females were more likely than males to report hesitation (23.0% vs 18.5%) and less likely to select definitely yes (29.1% vs 38.5%). By race and ethnicity, Black respondents exhibited the highest levels of hesitation and the lowest share of definitely-yes responses (25.9% and 19.4%) compared with White respondents (19.8% and 35.8%, respectively); Hispanic respondents showed patterns broadly similar to those of White respondents (Figure).

Figure. Bar Graphs of Willingness to Adopt a Preventive Dementia Vaccine Overall and by Age, Sex, and Race and Ethnicity.

These patterns persisted after adjustment for demographic and socioeconomic characteristics (Table). Older respondents compared with those aged 50 to 59 years were more willing to receive a dementia vaccine (60-69 years: odds ratio [OR], 1.46 [95% CI, 1.16-1.85], P = .002; ≥70 years: OR, 1.60 [95% CI, 1.26-2.02], P < .001). Females were less willing than males to receive a vaccine (OR, 0.74; 95% CI, 0.62-0.90; P = .002). Compared with White respondents, Black respondents were less willing (OR, 0.72; 95% CI, 0.54-0.97; P = .03), while no significant difference was observed for Hispanic respondents (OR, 1.06; 95% CI, 0.80-1.39; P = .69).

Table. Factors Associated With Willingness to Receive a Preventive Dementia Vaccine.

Variable	OR (95% CI)	P value
Race and ethnicitya
Hispanic	1.06 (0.80-1.39)	.69
Non-Hispanic Black	0.72 (0.54-0.97)	.03
Non-Hispanic White	1 [Reference]	NA
Age group, y
50-59	1 [Reference]	NA
60-69	1.46 (1.16-1.85)	.002
≥70	1.60 (1.26-2.02)	<.001
Sex
Male	1 [Reference]	NA
Female	0.74 (0.62-0.90)	.002
Household income, $
<30 000	1 [Reference]	NA
30 000-60 000	0.83 (0.64-1.09)	.18
>60 000-100 000	1.12 (0.86-1.47)	.41
>$100 000	1.64 (1.22-2.20)	.001
Educational level
<College	1 [Reference]	NA
≥College degree	1.44 (1.17-1.78)	<.001
Relative or someone close has dementia
No/do not know	1 [Reference]	NA
Yes	1.43 (1.19-1.73)	<.001

Abbreviations: NA, not applicable; OR, odds ratio.

^a Race and ethnicity were self-reported by participants. Hispanic ethnicity was assessed separately from race, and respondents were classified for this analysis as Hispanic, non-Hispanic Black, or non-Hispanic White. These groups were selected because they represent the largest racial and ethnic populations in the US and because Black and Hispanic adults experience a disproportionate burden of Alzheimer disease and related dementias.

Socioeconomic gradients were observed. Higher-income respondents (OR, 1.64; 95% CI, 1.22-2.20; P = .001) and those with a college degree or higher (OR, 1.44; 95% CI, 1.17-1.78; P < .001) were more willing to receive a vaccine. Respondents who reported that they or someone close to them had dementia were also more willing to receive the vaccine (OR, 1.43; 95% CI, 1.19-1.73; P < .001).

Discussion

In this nationally representative survey of US adults, willingness to receive a preventive dementia vaccine was generally high, with most respondents expressing willingness and relatively few expressing no intent, suggesting that uncertainty rather than opposition may be the principal barrier to adoption. Willingness varied systematically across sociodemographic groups, with greater intent among older respondents and less intent among women and Black respondents.

These findings are consistent with prior survey-based and related studies showing that willingness to adopt medical therapies varies across demographic groups.^8,9,10 Recent studies reporting associations between shingles vaccination and dementia risk among women^5,6 raise the possibility that women may benefit more from preventive vaccination; paradoxically, female respondents in our study were less willing to receive such a vaccine.

A study limitation is that willingness to receive a preventive vaccine was assessed using hypothetical vignettes and may not fully capture clinical decision-making. Our findings have important implications for the implementation of emerging preventive dementia vaccines, suggesting the need for targeted communication and engagement to ensure equitable uptake.

Supplement 1.

eMethods. Data Source, Survey Design, and Study Sample

eFigure. Preventive Dementia Vaccine Survey Question

eTable. Descriptive Characteristics of the Study Sample

Supplement 2.

Data Sharing Statement