Recombinant zoster vaccine and the risk of dementia.

Background: Herpes zoster is a potential risk factor for dementia. The effectiveness of the recombinant zoster vaccine for preventing dementia is uncertain.
Methods: This retrospective cohort study used de-identified claims data from the Optum Labs Data Warehouse database from January 1, 2017, to December 31, 2022, to determine whether the recombinant zoster vaccine is associated with a reduced risk of dementia. Immunocompetent patients with ≥365 days of continuous enrollment were included, with the risk period starting upon age-eligibility for the recombinant zoster vaccination. Cox regression adjusted for time-fixed and time-updated measures every six months was implemented to estimate hazard ratios for dementia. Herpes zoster diagnosis and antiviral therapy were also assessed.
Results: There were 4,502,678 individuals (median [IQR] age, 62 [54-71] years; 51 % female) included in this study: 206,297 (4.6 %) were partially vaccinated, and 460,413 (10.2 %) were fully vaccinated. The incidence rate of dementia was 99.1 cases per 10,000 person-years in the fully vaccinated group, 108.2 cases per 10,000 person-years in the partially vaccinated group, and 135.0 cases per 10,000 person-years in the unvaccinated group. After adjustment, vaccination was significantly associated with a decreased risk of dementia for two doses (hazard ratio (HR): 0.68; 95 % CI: 0.67-0.70; P < .001) and for one dose (HR 0.89; 95 % CI: 0.87-0.92; P < .001). Having a herpes zoster diagnosis before the first vaccination dose was associated with an increased hazard of dementia (HR 1.47; 95 % CI: 1.42-1.52; P < .001) compared to those with no diagnosis. Antivirals used to treat zoster infection were protective against dementia (HR 0.42; 95 % CI: 0.40-0.44; P < .001).
Conclusions: These findings suggest that the recombinant zoster vaccine is associated with a decreased risk of dementia and highlight an additional benefit of vaccination beyond preventing herpes zoster.
Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Nisha R. Acharya reports financial support was provided by National Eye Institute. Nisha R. Acharya reports financial support was provided by National Institutes of Health Office of Research on Women's Health. Benjamin F. Arnold reports financial support was provided by National Eye Institute. Nisha R. Acharya reports financial support was provided by Research to Prevent Blindness. Benjamin F. Arnold reports financial support was provided by Research to Prevent Blindness. Nisha R. Acharya reports a relationship with AbbVie Inc. that includes: non-financial support. Nisha R. Acharya reports a relationship with Roche that includes: consulting or advisory. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024. Published by Elsevier Ltd.)