P4‐361: Herpes zoster vaccine in the dementia population

Abstract

The effectiveness of herpes zoster (HZ) vaccine has been shown in the general population and in individual with chronic diseases. However, it has not been examined in the dementia population. The elderly dementia patients can potentially benefit from the vaccine. The goal of the study is to examine the association of HZ vaccine and incidence of HZ among a group of elderly who had ever been diagnosed as dementia. This cohort study included immunocompetent adults 60 years of age and older enrolling in Kaiser Permanente Southern California who had at least one diagnosis of dementia within 1 year prior to the observation period. Vaccinated cohort included 2,616 individuals who receive the herpes zoster vaccine during 01/01/2007 through 12/31/2011. The vaccinated cohort was age and sex-matched to five unvaccinated individual. Electronic health records were used to categorize individual regarding HZ incidence, vaccination status, and other confounders. Multiple Cox regression was used to estimate the hazard ratio (HR) and 95% confidence interval (CI) associated with HZ vaccination. Kaplan Meier method was used to estimate the cumulative incidence of HZ in the two cohorts. The number of herpes zoster cases among vaccinated and unvaccinated persons was 60 in 5,933 person-years (10.11 per 1,000; 95% CI, 7.7–13.0 per 1,000) and 328 in 26,212 person-years (12.5 per 1,000; 95% CI, 10.5–13.1 per 1,000), respectively. In adjusted analysis, vaccination was associated with a reduced risk of herpes zoster (HR=0.79; 95% CI, 0.60–1.04). The 60-month cumulative risk of HZ was 3.87% in the vaccinated cohort and 6.34% in the unvaccinated cohort. Among immunocompetent adults 60 years of age and older with dementia, receipt of HZ vaccine was associated with a lower incidence of HZ. However, the reduction in risk is not as significant as in the general population, probably due to advanced age in this study population. Nevertheless, dementia patients can potentially benefit from HZ vaccination to reduce the risk of this debilitating disease. More studies with larger size and longer observation are warranted.