Neuroticism, cortisol reactivity, and antibody response to vaccination.

This study examined whether neuroticism was related to the antibody response to influenza vaccination and whether the relationship was mediated by cortisol reactions to acute laboratory mental stress. Antibody status was assessed at baseline and to a trivalent influenza vaccination in 57 students at 5-week and 5-month follow-up. Neuroticism was also measured at baseline. Cortisol was measured at rest and in response to a pressurized mental arithmetic task. At both follow-ups, higher neuroticism scores were associated with poorer A/Panama antibody response, following adjustment for baseline antibody titer. Higher neuroticism scores were also associated with blunted cortisol reactivity, and blunted cortisol reactivity was associated with poorer A/Panama antibody response, but only at 5 months. However, there was no conclusive evidence that cortisol reactivity mediated the association between neuroticism and antibody response.