Abstract. Tseng HF, Liu A, Sy L, Marcy SM, Fireman B, Weintraub E, Baggs J, Weinmann S, Baxter R, Nordin J, Daley MF, Jackson L, Jacobsen SJ, for the Vaccine Safety Datalink (VSD) Team (Kaiser Permanente, Pasadena, CA; Kaiser Permanente, Oakland, CA; Centers for Disease Control and Prevention, Atlanta, GA; Kaiser Permanente, Portland, OR; HealthPartners Research Foundation, Minneapolis, MN; Kaiser Permanente, Denver, CO; and Group Health Cooperative of Puget Sound, Seattle, WA; USA). Safety of zoster vaccine in adults from a large managed-care cohort: a Vaccine Safety Datalink study. J Intern Med 2012; 271: 510–520.
Objectives. The aim of this study was to examine a large cohort of adults who received the zoster vaccine for evidence of an increased risk of prespecified adverse events requiring medical attention.
Design. Two self-comparison approaches, including a case-centred approach and a self-controlled case series (SCCS) analysis were used.
Setting. Eight managed-care organizations participating in the Vaccine Safety Datalink project in the United States.
Subjects. A total of 193 083 adults aged 50 and older receiving a zoster vaccine from 1 January 2007 to 31 December 2008 were included.
Main outcome measures. Prespecified adverse events were identified by aggregated International Classification of Diseases, Ninth Revision (ICD-9) codes in automated health plan datasets.
Results. The risk of allergic reaction was significantly increased within 1–7 days of vaccination [relative risk = 2.13, 95% confidence interval (CI): 1.87–2.40 by case-centred method and relative rate = 2.32, 95% CI: 1.85–2.91 by SCCS]. No increased risk was found for the following adverse event groupings: cerebrovascular events; cardiovascular events; meningitis; encephalitis; and encephalopathy; and Ramsay-Hunt syndrome and Bell’s palsy.
Conclusions. The results of this study support the findings from the prelicensure clinical trials, providing reassurance that the zoster vaccine is generally safe and well-tolerated with a small increased risk of allergic reactions in 1–7 days after vaccination.