Depression may inhibit herpes zoster vaccine

The protective effect of varicella zoster virus vaccine may be hindered in older patients with untreated depression, results of a study indicate.

Investigators with the University of Los Angeles Semel Institute for Neuroscience conducted a two-year longitudinal cohort study of 92 patients ages 60 and older, according to the study abstract. Forty patients with major depressive disorder, stratified by use of antidepressant medications, and 52 controls with no history of depression or other mental illness had their cell-mediated immunity measured before vaccination, at six weeks, one year and two years after vaccination.

The patients with untreated depression had lower levels of cell-mediated immunity than the nondepressed controls and the depressed patients who received antidepressants. Researchers noted that they found similar results when taking into account the time-varying status of depression and the use of antidepressants, as well as changes in depressive systems, during the post-vaccination period.

“Because higher levels of (varicella zoster virus-cell-mediated immunity) correlate with lower risk and severity of (herpes zoster), untreated depression may increase the risk and severity of (herpes zoster) and reduce the efficacy of zoster vaccine,” study authors concluded.

The study was published in Clinical Infectious Diseases.