Effect of a zoster vaccine on herpes zoster-related interference with functional status and health-related quality-of-life measures in older adults.

OBJECTIVE To determine the efficacy of a zoster vaccine on herpes zoster (HR)-related interference with activities of daily living (ADLs) and health-related quality of life (HRQL). DESIGN Randomized double-blind placebo controlled trial. SETTING Twenty-two U.S. sites. PARTICIPANTS Thirty eight thousand five hundred forty-six women and men aged 60 and olcer. MEASUREMENTS HZ burden of interference with ADLs and HRQL using ratings from the Zoster Brief Pain Inventory (ZBPI) and Medical Outcomes Study 12-item Short Form Survey (SF-12) mental component summary (MCS) and physical component summary (PCS) scores. Vaccine efficacy was calculated for the modified-intention-to-treat trial population and solely in participants who developed HZ. RESULTS For the modified-intention-to-treat population, the overall zoster vaccine efficacy was 66% (95% confidence interval (CI)=55-74%) for ZBPI ADL burden of interference score and 55% (95% CI=48-61%) for both the SF-12 MCS and PCS scores. Of participants who developed HZ, zoster vaccine reduced the ZBPI ADL burden of interference score by 31% (95% CI=12-51%) and did not significantly reduce the effect on HRQL. CONCLUSIONS Zoster vaccine reduced the burden of HZ-related interference with ADLs in the population of vaccinees and in vaccinees who developed HZ. Zoster vaccine reduced the effect of HZ on HRQL in the population of vaccinees but not in vaccinees who developed HZ.